JP2000154361A - Adhesive, adhesive member, wiring board equipped with the adhesive member for semiconductor, and semiconductor equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an adhesive having resistance to heat and moisture required when semiconductor chips mutually much different in coefficient of thermal expansion are mounted on a wiring board by making the adhesive include an epoxy resin, a specific resin, a specific copolymer and a hardening accelerator. SOLUTION: This adhesive is obtained by including (A) 100 pts.wt. of a mixture of (i) an epoxy resin and (ii) hardener for the component (ii), (B) 5 to 40 pts.wt. of a high-molecular-weight resin compatible with the component (i) and having a weight-average molecular weight of 30,000 or more, (C) 75 to 200 pts.wt. of an acrylic-based copolymer containing 0.5 to 2 wt.% of glycidyl (meth)acrylate, having a glass transition temperature of -10 deg.C or higher and weight-average molecular weight of 800,000 or more, and containing epoxy group, (D) 0.1 to 5 pts.wt. of a hardening accelerator, and, as required, (E) 1 to 20 pts.vol. of an inorganic filler per 100 pts.vol. of the adhesive resin. More concretely, the component (ii) is preferably a phenolic resin, and component (B) is preferably a phenoxy resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive, a bonding member, a wiring board for mounting a semiconductor provided with the bonding member, and a semiconductor device in which a semiconductor chip and a wiring board are bonded using the bonding member.

[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 semiconductors having a size substantially equal to the size of a semiconductor chip called a chip scale package or a chip size package (hereinafter referred to as a CSP). New types of mounting methods, such as package and semiconductor bare chip mounting, are beginning to be adopted.

One of the most important characteristics of a mounting board on which various electronic components such as semiconductor elements are mounted is reliability. Among them, the connection reliability against thermal fatigue is a very important item because it is directly related to the reliability of the device using the mounting board. As a cause of reducing the connection reliability, there is a thermal stress caused by using various materials having different thermal expansion coefficients. This is because the thermal expansion coefficient of a semiconductor chip is as small as about 4 ppm / ° C., whereas the thermal expansion coefficient of a wiring board on which electronic components are mounted is as large as 15 ppm / ° C. or more, so that thermal strain is generated due to thermal shock. ,
Thermal stress is generated by the thermal strain. In a substrate on which a semiconductor package having a lead frame such as a conventional QFP or SOP is mounted, reliability is maintained by absorbing thermal stress at the lead frame portion. However, bare chip mounting employs a method of connecting the electrodes of the semiconductor chip to the wiring pads of the wiring board using solder balls, or a method of forming small projections called bumps and connecting them with conductive paste. The connection reliability was reduced by focusing on the connection part. It has been found that it is effective to inject a resin called an underfill between the chip and the wiring board in order to disperse the thermal stress, but the number of mounting steps has been increased, resulting in an increase in cost. There is also a method of connecting the electrodes of the semiconductor chip and the wiring pads of the wiring board using conventional wire bonding, but the sealing material resin had to be coated to protect the wires, which also increased the mounting process. .

Since the CSP can be mounted together with other electronic components, the surface mounting technology published by Nikkan Kogyo Shimbun, 1997-
No. 3 article “CSP (Fine-pitch BG has entered practical use)
Various structures such as those shown in Table 1 on page 5 of "A)" have been proposed. Among them, a system using a tape or a carrier substrate for a wiring substrate called an interposer has been put into practical use. This includes the methods developed by Tessera and TI in the table above.
Since these pass through a wiring board called an interposer, IEICE Technical Report CPM 96-121, ICD 96-16
0 (1996-12) "Development of Tape BGA Type CSP" and Sharp Technical Report No. 66 (1996-12) "Chip Size Package (Chip Size Package)
Ge) Development ”, it shows excellent connection reliability. It is preferable to use an adhesive member between the semiconductor chips of these CSPs and a wiring board called an interposer so as to reduce thermal stress caused by a difference in thermal expansion coefficient between the semiconductor chips. In addition, moisture resistance and high-temperature durability are required. Further, a film-type adhesive member is required for easy management of the manufacturing process.

[0005] Film-type adhesives are used for flexible printed wiring boards and the like, and many of them use acrylonitrile-butadiene rubber as a main component. As a printed wiring board-related material having improved moisture resistance, there is an adhesive containing an acrylic resin, an epoxy resin, a polyisocyanate and an inorganic filler described in JP-A-60-243180. 6
There is an acrylic resin, an epoxy resin, and an adhesive containing a primary amine compound having a urethane bond in each molecule at both ends and a primary amine compound and an inorganic filler described in 1-1138680.

[0006]

As a film-type adhesive, a system containing acrylonitrile-butadiene rubber as a main component is often used. However, there are drawbacks such as a large decrease in adhesive strength after long-time treatment at a high temperature and inferior electric corrosion resistance. 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. JP-A-60-243180,
In what is disclosed in JP-A-61-138680,
When a moisture resistance test was performed under severe conditions such as a PCT treatment, deterioration was large.

When a semiconductor chip is mounted on a wiring board using an adhesive as a material related to the printed wiring board, a difference in thermal expansion coefficient between the semiconductor chip and a wiring board called an interposer is large, and cracks occur during reflow. Could not be used for. Further, when a humidity resistance test under severe conditions such as a temperature cycle test or a PCT treatment was performed, the deterioration was large and the device could not be used.

The present invention provides an adhesive, an adhesive member having heat resistance and moisture resistance necessary for mounting a semiconductor chip having a large difference in thermal expansion coefficient on a wiring board called an interposer such as a glass epoxy board or a flexible board. It is an object of the present invention to provide a wiring board for mounting a semiconductor provided with this adhesive member, and a semiconductor device in which a semiconductor chip and a wiring board are bonded using the adhesive member.

[0009]

According to the present invention, there are provided (1) 100 parts by weight of an epoxy resin and a curing agent thereof, and (2) a high molecular weight resin having a weight average molecular weight of 30,000 or more, which is compatible with the epoxy resin. 40 parts by weight, (3) an epoxy group-containing acrylic copolymer having a Tg (glass transition temperature) of -10 ° C or more and a weight average molecular weight of 800,000 or more containing 0.5 to 2% by weight of glycidyl (meth) acrylate. Combined 75-200
(4) An adhesive containing 0.1 to 5 parts by weight of a curing accelerator. Specifically, a curing agent for the epoxy resin is a phenol resin, and a phenoxy resin which is compatible with the epoxy resin and has a weight average molecular weight of 30,000 or more is used.
Parts by weight, (2) 5 to 40 parts by weight of phenoxy resin, (3)
75 to 200 parts by weight of an epoxy group-containing acrylic copolymer having a Tg (glass transition temperature) of -10 ° C. or more and a weight average molecular weight of 800,000 or more containing 0.5 to 2% by weight of glycidyl (meth) acrylate; (4) Curing accelerator 0.1
Preferably, the adhesive contains up to 5 parts by weight. Also, the present invention provides (1) 100 parts by weight of an epoxy resin and a curing agent thereof, (2) glycidyl (meth) acrylate 0.5 to 2
75 to 200 parts by weight of an epoxy group-containing acrylic copolymer having a Tg (glass transition temperature) of −10 ° C. or more and a weight average molecular weight of 800,000 or more containing 3% by weight; An adhesive containing 5 parts by weight. Specifically, the curing agent of the epoxy resin is a phenol resin (1) 100 parts by weight of the epoxy resin and the phenol resin,
(2) an epoxy group-containing acrylic copolymer having a Tg (glass transition temperature) of -10 ° C or more and a weight average molecular weight of 800,000 or more containing 0.5 to 2% by weight of glycidyl (meth) acrylate; It is preferable that the adhesive contains 0.1 to 5 parts by weight of a curing accelerator (3).
The adhesive of the present invention comprises an inorganic filler having an adhesive resin content of 100.
It is preferable to contain 1 to 20 parts by volume based on the volume, and it is preferable that the inorganic filler is at least one of alumina, silica, aluminum hydroxide, and antimony oxide. Also,
The adhesive of the present invention preferably has an adhesive obtained by heating and drying the above adhesive, and generates 10 to 40% of the heat generated by the total curing calorific value when measured by DSC (differential scanning calorimetry). It is in a state where it has been completed. Also, preferably,
The adhesive has a residual solvent amount of 5% by weight or less.
The storage elastic modulus of the cured adhesive measured by a dynamic viscoelasticity measuring device is preferably 20 to 2,000 M at 25 ° C.
Pa and an adhesive that is 3 to 50 MPa at 250 ° C.

The present invention is a film-like adhesive member obtained by forming the above-mentioned adhesive on a carrier film, and is an adhesive member obtained by forming the adhesive on both surfaces of a core material. A preferred core material is a heat-resistant thermoplastic film. Specifically, those having a property of a softening point of 260 ° C. or more, specifically, polyamide imide, polyimide, polyether imide, polyether sulfone,
It is an adhesive member using polytetrafluoroethylene, ethylene tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkylvinyl ether copolymer or a liquid crystal polymer. As for these core materials, not only a smooth film but also a porous film may be used.

Further, the present invention is a wiring board for mounting a semiconductor, comprising the above-mentioned adhesive member having excellent moisture resistance.

Further, the present invention is a semiconductor device in which a semiconductor chip and a wiring substrate called an interposer are bonded using the bonding member having excellent moisture resistance. In particular, a semiconductor device in which the area of the semiconductor chip is 70% or more of the area of the wiring board.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy resin used in the present invention is only required to be cured and exhibit an adhesive action.
An epoxy resin having two or more functional groups, preferably having a molecular weight of less than 5000, more preferably less than 3000 can be used.
Examples of the bifunctional epoxy resin include a bisphenol A type or bisphenol F type resin. The bisphenol A type or bisphenol F type liquid resin is commercially available from Yuka Shell Epoxy Co., Ltd. under the trade names of Epikote 807, Epikote 827 and Epikote 828. In addition, Dow Chemical Japan Co., Ltd.
E. FIG. R. 330, D.I. E. FIG. R. 331; E. FIG. R. 3
It is commercially available under the trade name 61. Further, they are commercially available from Toto Kasei Corporation under the trade names of YD8125 and YDF8170.

As the epoxy resin, a polyfunctional epoxy resin may be added for the purpose of increasing Tg. Examples of the polyfunctional epoxy resin include a phenol novolak epoxy resin and a cresol novolak epoxy resin. The phenol novolak epoxy resin is commercially available from Nippon Kayaku Co., Ltd. under the trade name EPPN-201. Cresol novolak type epoxy resin was obtained from Sumitomo Chemical Co., Ltd., ESCN-190, ESCN-19.
It is commercially available under the trade name 5. Further, from the Nippon Kayaku Co., Ltd., EOCN1012, EOCN1025,
It is commercially available under the trade name EOCN1027. In addition, YDCN701, YDN
It is commercially available under the trade names CN702, YDCN703, and YDCN704.

As the curing agent for the epoxy resin, those usually used as curing agents for the epoxy resin can be used, and amine, polyamide, acid anhydride, polysulfide, boron trifluoride and phenolic hydroxyl group are contained in one molecule. Bisphenol A, bisphenol F,
Bisphenol S etc. are mentioned. In particular, it is preferable to use a phenol resin such as a phenol novolak resin, a bisphenol novolak resin, or a cresol novolak resin because of excellent electric corrosion resistance during moisture absorption. Preferred curing agents are phenolite LF2882 and phenolite L from Dainippon Ink and Chemicals, Inc.
F2822, phenolite TD-2090, phenolite TD-2149, phenolite VH4150, and phenolite VH4170 are commercially available.

It is preferable to use a curing accelerator together with the curing agent, and it is preferable to use various imidazoles as the curing accelerator. Examples of imidazole include 2-methylimidazole, 2-ethyl-4-methylimidazole,
Examples thereof include 1-cyanoethyl-2-phenylimidazole and 1-cyanoethyl-2-phenylimidazolium trimellitate. Imidazoles were obtained from Shikoku Chemicals Corporation, 2E4MZ, 2PZ-CN, 2PZ-CN.
It is marketed under the trade name S.

The high molecular weight resin compatible with the epoxy resin and having a weight average molecular weight of 30,000 or more includes a phenoxy resin, a high molecular weight epoxy resin, an ultrahigh molecular weight epoxy resin, a highly polar functional group-containing rubber, and a highly polar rubber. And functional group-containing reactive rubber. The weight average molecular weight is set to 30,000 or more in order to reduce the tackiness of the adhesive in the B stage and improve the flexibility at the time of curing. Examples of the highly polar functional group-containing reactive rubber include a rubber obtained by adding a highly polar functional group such as a carboxyl group to an acrylic rubber. Here, the compatibility with the epoxy resin means that
It refers to the property of forming a homogeneous mixture without being separated from the epoxy resin after curing and separating into two or more phases. The amount of the high-molecular-weight resin compatible with the epoxy resin and having a weight-average molecular weight of 30,000 or more is insufficient in flexibility of a phase mainly composed of the epoxy resin (hereinafter referred to as epoxy resin phase) and reduces tackiness. The amount is 5 parts by weight or more to prevent a decrease in insulation due to cracks or the like, and 40 parts by weight or less to prevent a decrease in Tg of the epoxy resin phase. Phenoxy resin is
It is commercially available from Toto Kasei Co., Ltd. under the trade names Phenothote YP-40 and Phenothote YP-50. In addition, PKHC, PKH from Phenoxy Associates
H and PKHJ are commercially available. The high-molecular-weight epoxy resin is a high-molecular-weight epoxy resin having a molecular weight of 30,000 to 80,000, and an ultra-high-molecular-weight epoxy resin having a molecular weight exceeding 80,000 (Japanese Patent Publication No. 7-59617, Japanese Patent Publication No. 7-596).
No. 18, No. 7-59619, No. 7-5962
No. 0, Tokiko 7-64911, Tokiko 7-68327
All publications are manufactured by Hitachi Chemical Co., Ltd. As a highly polar functional group-containing reactive rubber, a carboxyl group-containing acrylic rubber is commercially available from Teikoku Chemical Industry Co., Ltd. under the trade name of HTR-860P.

Glycidyl (meth) acrylate 0.5 to
An epoxy group-containing acrylic copolymer having a Tg of −10 ° C. or more and a weight average molecular weight of 800,000 or more containing 2% by weight is commercially available from Teikoku Chemical Industry Co., Ltd. under the trade name HTR-860P-3DR ( C) can be used. When the functional group monomer uses carboxylic acid type acrylic acid or hydroxyl group type hydroxymethyl (meth) acrylate, the cross-linking reaction proceeds easily, resulting in gelation in a varnish state and an increase in the degree of curing in a B-stage state. It is not preferable because there is a problem such as a decrease in adhesive strength. The amount of glycidyl (meth) acrylate used as the functional group monomer is set to a copolymer ratio of 0.5 to 2% by weight. In order to ensure heat resistance, the content is set to 0.5% by weight or more, and in order to reduce the amount of added rubber and increase the varnish solid content ratio, the content is set to 2% by weight or less. If it exceeds 2% by weight, a large amount of an epoxy group-containing acrylic copolymer is required to reduce the elastic modulus of the cured adhesive. Since the epoxy group-containing acrylic copolymer has a high molecular weight, the viscosity of the adhesive varnish increases as the weight ratio increases. If the varnish viscosity is high, it becomes difficult to form a film, and the varnish is diluted with an appropriate amount of a solvent for the purpose of decreasing the viscosity. In this case, the solid content of the adhesive varnish decreases, the amount of the adhesive varnish produced increases, and the production efficiency decreases. Ethyl (meth) acrylate, butyl (meth) acrylate or a mixture of both can be used for the remainder other than glycidyl (meth) acrylate, but the mixing ratio is determined in consideration of the Tg of the copolymer. If the Tg is less than -10 ° C, the tackiness of the adhesive film in the B-stage state is increased and the handling property is deteriorated. Examples of the polymerization method include pearl polymerization, solution polymerization, and the like, which can be obtained. The weight average molecular weight of the epoxy group-containing acrylic copolymer is 800,000 or more.
This is because there is little decrease in strength and flexibility and increase in tackiness in the form of a film. Also, as the molecular weight increases, the flowability decreases and the circuit filling of the wiring decreases,
The weight average molecular weight of the epoxy group-containing acrylic copolymer is preferably 2,000,000 or less. The compounding amount of the epoxy group-containing acrylic copolymer is set to 75 parts by weight or more in order to reduce the elastic modulus and suppress flowability during molding. When the compounding amount of the epoxy group-containing acrylic copolymer increases, the rubber component Since the number of phases increases and the number of epoxy resin phases decreases, the handleability at high temperatures deteriorates.

In order to improve the interfacial bonding between different kinds of materials, a coupling agent may be added to the adhesive.
Examples of the coupling agent include a silane coupling agent, a titanate coupling agent, and an aluminum coupling agent. Among them, the 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 can be mentioned. The above-mentioned silane coupling agents include NUC A-187 for γ-glycidoxypropyltrimethoxysilane, NUC A-189 for γ-mercaptopropyltrimethoxysilane, NUC A-1100 for γ-aminopropyltriethoxysilane, γ −
Ureidopropyltriethoxysilane is NUC A-1
160, and N-β-aminoethyl-γ-aminopropyltrimethoxysilane are commercially available from Nippon Unicar Co., Ltd. under the trade name of NUC A-1120. The compounding amount of the coupling agent is 0.1 to 100 parts by weight of the resin, based on the effect of the addition, heat resistance and cost.
It is preferable to add 10 parts by weight.

Further, in order to adsorb ionic impurities and improve insulation reliability at the time of moisture absorption, an ion scavenger can be blended. The compounding amount of the ion scavenger is preferably 1 to 10 parts by weight from the viewpoint of the effect of the addition, heat resistance and cost. 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. As the bisphenol-based reducing agent, 2,2′-methylene-bis- (4-methyl-
6-tert-butylphenol), 4,4'-thio-bis- (3-methyl-6-tert-butylphenol) and the like. Further, an inorganic ion adsorbent can be blended. Examples of the inorganic ion adsorbent include a zirconium compound, an antimony bismuth compound, and a magnesium aluminum compound. A copper damage inhibitor containing a triazine thiol compound as a component is commercially available from Sankyo Pharmaceutical Co., Ltd. under the trade name Disnet DB. 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. Various inorganic ion adsorbents are commercially available from Toa Gosei Chemical Industry Co., Ltd. under the trade name IXE.

Further, the adhesive of the present invention preferably contains an inorganic filler for the purpose of improving the handleability of the adhesive, improving the thermal conductivity, adjusting the melt viscosity, imparting thixotropic properties, and the like. . As inorganic fillers, aluminum hydroxide (aluminum hydroxide), magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, aluminum nitride, aluminum borate whisker, boron nitride, Crystalline silica, amorphous silica,
Antimony oxide and the like. For improving the thermal conductivity, alumina, aluminum nitride, boron nitride, crystalline silica, amorphous silica and the like are preferable. For the purpose of adjusting melt viscosity and imparting thixotropic properties, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, crystalline silica, Crystalline silica and the like are preferred. Further, in addition to the above, alumina, silica, aluminum hydroxide, and antimony oxide which improve moisture resistance are preferable. The amount of the inorganic filler is preferably 1 to 20 parts by volume based on 100 parts by volume of the adhesive resin component. From the viewpoint of the effect of the compounding, if the compounding amount is 1 part by volume or more and the compounding amount is large, 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 the remaining voids are caused. It is preferable to set the following.

The film-like adhesive member according to the present invention comprises:
A varnish is prepared by dissolving or dispersing each component of the adhesive in a solvent, applied to a carrier film, and heated to remove the solvent, thereby forming an adhesive layer on the carrier film. As the carrier film, a plastic film such as a polytetrafluoroethylene film, a polyethylene terephthalate film, a release-treated polyethylene terephthalate film, a polyethylene film, a polypropylene film, a polymethylpentene film, and a polyimide film can be used. The carrier film can be peeled off at the time of use and only the adhesive film can be used, or used together with the carrier film,
It can be removed later. As an example of the carrier film used in the present invention, a polyimide film is commercially available from Toray DuPont under the trade name Kapton and from Kanegafuchi Chemical Co., Ltd. under the trade name Apical. Polyethylene terephthalate film is commercially available from Toray DuPont under the trade name Lumirror and from Teijin Limited under the trade name Purex.

Solvents for varnishing include relatively low boiling methyl ethyl ketone, acetone, methyl isobutyl ketone,
It is preferable to use 2-ethoxyethanol, toluene, butyl cellosolve, methanol, ethanol, 2-methoxyethanol and 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, dimethylformamide, methylpyrrolidone, cyclohexanone and the like. The production of the varnish can be carried out by a mill, a three-roll mill, a bead mill or the like, or a combination thereof, in consideration of the dispersion of the inorganic filler.
By mixing the filler and the low molecular weight material in advance and then blending the high molecular weight material, the time required for mixing can also be reduced. After the varnish is formed, it is preferable to remove bubbles in the varnish by vacuum degassing.

An adhesive member consisting of only a film-like adhesive can be produced by applying an adhesive varnish on a carrier film such as a plastic film and drying by heating to remove the solvent. The resulting adhesive is DS
It is preferable that the heat generation of 10 to 40% of the total curing calorific value measured using C is completed. Heat is applied when the solvent is removed. At this time, the curing reaction of the adhesive composition 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 the 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 reaction of the resin composition is an exothermic reaction, and when the sample is heated at a constant heating 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 300 ° 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 obtained by applying and drying the above-mentioned carrier film is determined as follows. First, the total calorific value of the uncured sample obtained by drying the solvent using a vacuum dryer at 25 ° C. was measured.
(J / g). Next, the calorific value of the coated and dried sample was measured, and this was designated as B. Curing degree of sample C (%)
(The state in which heat generation has been completed by heating and drying) is given by the following Equation 1.

[0025]

## EQU1 ## C (%) = (A−B) × 100 / A

The thickness of the adhesive member consisting of the film adhesive alone is preferably 25 to 250 μm, but is not limited thereto. When the thickness is smaller than 25 μm, the effect of relaxing the stress is poor. In addition, by bonding a plurality of adhesive films, an adhesive member having a desired thickness can be obtained. In this case, laminating conditions are required so that peeling of the adhesive films does not occur.

The adhesive member of the present invention may be one in which an adhesive is formed on both surfaces of a core material. Core material thickness is 5
It is preferably within the range of 200 μm, but is not limited. The thickness of the adhesive formed on both surfaces of the core material is preferably in the range of 10 to 200 μm. If it is thinner than this, the adhesiveness and stress relaxation effect are poor, and if it is thicker, it is not economical, but it is not limited.

The film used as the core material in the present invention is preferably a heat-resistant thermoplastic film using a polymer having a softening point of 260 ° C. or higher, a liquid crystal polymer, a fluorine-based polymer, or the like. Imide, polyether sulfone, wholly aromatic polyester, polytetrafluoroethylene, ethylene tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer and the like are preferably used. Further, as the core material, a porous film can be used to reduce the elastic modulus of the adhesive member. When a thermoplastic film having a softening point temperature of less than 260 ° C. is used as the core material, peeling from the adhesive may occur at a high temperature such as during solder reflow. The polyimide film is commercially available from Ube Industries under the trade name Upilex, from Toray Dupont under the trade name Kapton, and from Kanegabuchi Chemical Co., Ltd. under the trade name Apical. The polytetrafluoroethylene film is commercially available from Mitsui-Dupont Fluorochemicals Co., Ltd. under the trade name Teflon, and from Daikin Industries, Ltd. under the trade name Polyflon. The ethylene tetrafluoroethylene copolymer film is commercially available from Asahi Glass Co., Ltd. under the trade name AFLON COP, and from Daikin Industries, Ltd. under the trade name NEOFLON ETFE. The tetrafluoroethylene-hexafluoropropylene copolymer film is commercially available from DuPont-Mitsui Fluorochemicals Co., Ltd. under the trade name of Teflon FEP, and from Daikin Industries, Ltd. under the trade name of Neoflon FEP. The tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer film is commercially available from Mitsui-DuPont Fluorochemicals Co., Ltd. under the trade name Teflon PFA, and from Daikin Industries, Ltd. under the trade name NEOFLON PFA. Liquid crystal polymer films are commercially available from Kuraray Co., Ltd. under the trade name Vectra. Further, a porous polytetrafluoroethylene film is commercially available from Sumitomo Electric Industries, Ltd. under the trade name Poreflon, and from Japan Gore-Tex Corporation under the trade name Gore-Tex.

The adhesive formed on both sides of the core material can be made into a varnish by dissolving or dispersing each component of the adhesive in a solvent. The adhesive layer can be formed on the heat-resistant thermoplastic film by applying the varnish on a heat-resistant thermoplastic film serving as a core material, heating and removing the solvent. By performing this step on both sides of the heat-resistant thermoplastic film, an adhesive member having an adhesive formed on both sides of the core material can be produced. In this case, it is desirable to protect the surface with a cover film so that the adhesive layers on both sides do not block each other. However, when blocking does not occur, it is preferable not to use a cover film for economic reasons, and there is no limitation. A varnish obtained by dissolving or dispersing each component of the adhesive in a solvent is coated on the above-mentioned carrier film, and the solvent is removed by heating to form an adhesive layer on the carrier film. By bonding the agent layer to both surfaces of the core material, an adhesive member having an adhesive formed on both surfaces of the core material can be produced. In this case, a carrier film can be used as the cover film. The adhesive formed on both sides of the core material is in a state where 10 to 40% of the total curing calorific value measured using DSC has been completed for the same reason as the adhesive member composed of only the film adhesive. Is preferred.

The storage elastic modulus of the cured adhesive of the present invention measured by a dynamic viscoelasticity measuring apparatus is 20 to 2,000 at 25 ° C.
It is preferable to have a low elastic modulus of 3 to 50 MPa at 260 ° C. and MPa. The storage elastic modulus is measured by applying a tensile load to the adhesive cured product at a frequency of 10 Hz and a temperature rising rate of 5 to 10 ° C. /
The measurement was performed in a temperature-dependent measurement mode in which the temperature was measured from -50 ° C to 300 ° C in minutes. 2,000MP at 25 ° C
When the temperature exceeds 260 MPa and the temperature exceeds 260 MPa at 260 ° C., the effect of relieving the thermal stress caused by the difference in the thermal expansion coefficient between the semiconductor chip and the interposer, which is the wiring substrate, becomes small, and there is a possibility that peeling or cracking may occur. is there. On the other hand, when the storage elastic modulus is less than 20 MPa at 25 ° C., the handleability of the adhesive and the thickness accuracy of the adhesive layer are deteriorated, and
If the temperature is lower than 3 MPa at a temperature of about 0 ° C., reflow cracks are easily generated.

The wiring board used for the wiring board for mounting a semiconductor of the present invention can be used without being limited to the material of the board such as a ceramic board or an organic board. As the ceramic substrate, an alumina substrate, an aluminum nitride substrate, or the like can be used. As the organic substrate, an FR-4 substrate in which a glass cloth is impregnated with an epoxy resin, a BT substrate in which a bismaleimide-triazine resin is impregnated, and a polyimide film substrate using a polyimide film as a base material can be used. . The shape of the wiring may be any of single-sided wiring, double-sided wiring, and multi-layered wiring, and if necessary, a through-hole or a non-through-hole electrically connected may be provided. Further, when the wiring appears on the outer surface of the semiconductor device, it is preferable to provide a protective resin layer. As a method of attaching the adhesive member to the wiring board, a method of cutting the adhesive member into a predetermined shape and thermocompression bonding the cut adhesive member to a desired position on the wiring board is general, but is not limited thereto. It does not do.

The structure of the semiconductor device of the present invention includes a structure in which the electrodes of the semiconductor chip and the wiring board are connected by wire bonding, and a structure in which the electrodes of the semiconductor chip and the wiring board are connected by inner leads of tape automated bonding (TAB). There are structures connected by bonding, etc., but the present invention is not limited to these structures, and any of them is effective. A method for assembling a semiconductor device using an adhesive member will be described with reference to FIGS. 1 to 3 as examples, but the present invention is not limited to this. The adhesive member may be an adhesive member that is a film-like adhesive 1 as shown in FIG. 1A, or may be an adhesive member having an adhesive 1 on both sides of a core material 2 as shown in FIG. 1B. On the wiring side of the wiring board 4 on which the wiring 3 shown in FIGS. 2A and 2B is formed, an adhesive member cut out to a predetermined size is thermocompression-bonded at, for example, 140 ° C., 0.5 MPa, and 5 seconds. Then, a wiring board for mounting a semiconductor provided with an adhesive member is obtained.
Thermocompression bonding at 70 ° C, 1 MPa, 5 seconds, 170 ° C,
After heating for one hour to cure the adhesive layer of the adhesive member, the pads of the semiconductor chip and the wiring on the wiring board are connected by bonding wires 6 in FIGS. 3A and 3B.
In (c) and (d), the inner lead 6 ′ of the substrate is bonded to the pad of the semiconductor chip and sealed with the sealing material 7.
A semiconductor device can be obtained by providing solder balls as the external connection terminals 8. The thermal stress generated between the semiconductor chip and the wiring board is remarkable when the area difference between the semiconductor chip and the wiring board is small. However, the semiconductor device according to the present invention uses a low elastic modulus adhesive member for electronic components to generate the heat stress. This is to relieve stress and ensure reliability. Further, when the adhesive member is made flame-retardant, it has flame retardancy as a semiconductor device. These effects are very effective when the area of the semiconductor chip is 70% or more of the area of the wiring board. In a semiconductor device having a small area difference between a semiconductor chip and a wiring board, external connection terminals are often provided in an area.

The present invention is characterized in that an epoxy group-containing acrylic copolymer and an epoxy resin-based adhesive have a low elastic modulus near room temperature and are excellent in moisture resistance. Since the epoxy group-containing acrylic copolymer has a low elastic modulus near room temperature, increasing the mixing ratio of the epoxy group-containing acrylic copolymer causes a difference in the thermal expansion coefficient between the semiconductor chip and the wiring board. Thus, cracks can be suppressed by the effect of relaxing the stress generated in the heating / cooling process at the time of reflow. In addition, the epoxy group-containing acrylic copolymer has excellent reactivity with the epoxy resin, and the cured product of the adhesive is chemically and physically stable, so that it exhibits excellent performance in a moisture resistance test represented by PCT processing. .

Furthermore, in the present invention, the epoxy resin and the high molecular weight resin have good compatibility and are uniform, and the epoxy groups contained in the acrylic copolymer partially react with them, and unreacted epoxy Since the whole including the resin is crosslinked and gelled, it suppresses the fluidity and does not impair the handling even when a large amount of epoxy resin or the like is included. 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 is dried, the epoxy group and the epoxy resin contained in the epoxy group-containing acrylic copolymer react together, but the epoxy group-containing acrylic copolymer has a large molecular weight and a large number of epoxy groups in one molecular chain. Because it is included, it gels even when the reaction proceeds slightly. Normally, gelation occurs in a state where heat generation of 10 to 40% of the total curing calorific value measured by DSC is completed, that is, in the first half of the A or B stage. for that reason,
Gelled with a large amount of unreacted components such as epoxy resin, compared to the case where the melt viscosity is not gelled,
It is greatly increased, and does not impair handling. In addition, when pressure is applied, unreacted components exude from the gel, and therefore, even when gelled, the adhesiveness is hardly reduced.
Further, since the adhesive can be formed into a film in a state containing a large amount of unreacted components such as an epoxy resin, there is an advantage that the life (effective use period) of the film adhesive is extended.

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. It is not clear how easily the epoxy group contained in the acrylic copolymer reacts with the epoxy group of the low molecular weight epoxy resin, but it is sufficient that the epoxy copolymer has at least the same reactivity. It is not necessary that only the epoxy groups contained in the polymer react selectively. 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 20% of a total curing calorific value measured by using DSC has been completed. The B stage is in a state in which curing and gelation are slightly advanced, and a state in which heat generation of 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.

The semiconductor device in which the semiconductor chip and the wiring board were bonded using the bonding member of the present invention was excellent in reflow resistance, temperature cycle test, moisture resistance (PCT resistance) and the like. Furthermore, the solid content of the adhesive varnish was high, and the efficiency of the production of the adhesive material could be increased. Hereinafter, the present invention will be described more specifically with reference to examples.

[0037]

EXAMPLES (Adhesive Varnish 1) As an epoxy resin, 45 parts by weight of a bisphenol A type epoxy resin (epoxy equivalent: 190, trade name: Epicoat 828 manufactured by Yuka Shell Epoxy Co., Ltd.), cresol novolac type epoxy resin (epoxy equivalent: 195) 15 parts by weight of a phenol novolak resin as a curing agent for epoxy resin (Plyofen LF288 manufactured by Dainippon Ink and Chemicals, Inc.)
Phenoxy resin (molecular weight: 50,000; trade name: Phenotote YP-50 manufactured by Toto Kasei Co., Ltd.) as a high-molecular-weight resin having a weight-average molecular weight of 30,000 or more, which is 40 parts by weight, which is compatible with the epoxy resin. 15 parts by weight, an epoxy group-containing acrylic rubber as an epoxy group-containing acrylic polymer (molecular weight 1,000,000, Tg-7 ° C., glycidyl methacrylate 1% by weight, trade name HTR manufactured by Teikoku Chemical Industry Co., Ltd.)
-860P-3DR (C)) 100 parts by weight, 1-cyanoethyl-2-phenylimidazole (Curesol 2PZ manufactured by Shikoku Chemicals Co., Ltd.) as a curing accelerator
0.5 parts by weight, γ-glycidoxypropyltrimethoxysilane as a silane coupling agent (trade name NUCA-187 manufactured by Nippon Unicar Co., Ltd.)
To a composition consisting of 0.7 parts by weight, methyl ethyl ketone was added, mixed with stirring, and degassed under vacuum. The adhesive varnish was applied on a release-treated polyethylene terephthalate film having a thickness of 75 μm, and dried by heating at 140 ° C. for 5 minutes to form a coating film having a thickness of 80 μm, thereby producing an adhesive film. The adhesive film was cured by heating at 170 ° C. for 1 hour, and its storage elastic modulus was measured using a dynamic viscoelasticity measuring device (DVE-V4, manufactured by Rheology) (sample size:
Length 20 mm, width 4 mm, film thickness 80 μm, heating rate 5 ° C.
/ Min, tensile mode, 10 Hz, automatic static load), the result was 360 MPa at 25 ° C and 4 MPa at 260 ° C. The solid content of the adhesive varnish was 28% by weight.
The solid content of the adhesive varnish is a value such that the varnish viscosity is about 100 poise (25 ° C.). If the solid content is increased to increase the viscosity, the variation in thickness increases (the same applies hereinafter).

(Adhesive Varnish 2) Bisphenol A type epoxy resin (epoxy equivalent: 175,
(Tokyo Kasei Co., Ltd. product name YD-8125 is used) 45
Parts by weight, cresol novolac type epoxy resin (epoxy equivalent 210, trade name YDCN-7 manufactured by Toto Kasei Co., Ltd.)
No. 03) 15 parts by weight, phenol novolak resin as epoxy resin curing agent (Plyofen LF2882 manufactured by Dainippon Ink and Chemicals, Inc.) 4
0 parts by weight, an epoxy group-containing acrylic rubber as an epoxy group-containing acrylic polymer (molecular weight 1,000,000, glycidyl methacrylate 1% by weight, Tg-7 ° C, trade name HTR-860P-3DR (C) manufactured by Teikoku Chemical Industry Co., Ltd.) use)
75 parts by weight, 1-cyanoethyl-2- as a curing accelerator
To a composition consisting of 0.5 parts by weight of phenylimidazole (trade name: Curesol 2PZ-CN manufactured by Shikoku Chemical Industry Co., Ltd.), methyl ethyl ketone was added, and the mixture was stirred and mixed.
Vacuum degassed. The adhesive varnish was applied on a release-treated polyethylene terephthalate film having a thickness of 75 μm, and dried by heating at 140 ° C. for 5 minutes to form a coating film having a thickness of 80 μm, thereby producing an adhesive film. This adhesive film was cured by heating at 170 ° C. for 1 hour, and its storage elastic modulus was measured by a dynamic viscoelasticity measuring device (DVE-V4, manufactured by Rheology Co., Ltd.).
(Sample size: length 20mm, width 4m)
m, film thickness 80 μm, heating rate 5 ° C./min, tensile mode,
10Hz, automatic static load), as a result, 600MP at 25 ° C
a, 5 MPa at 260 ° C. The solid content of the adhesive varnish was 32% by weight.

(Adhesive Varnish 3) A bisphenol A type epoxy resin (epoxy equivalent 190,
Yuka Shell Epoxy Co., Ltd. Epicoat 828
30 parts by weight, cresol novolak type epoxy resin (epoxy equivalent: 195, trade name: ESCN195 manufactured by Sumitomo Chemical Co., Ltd.) 30 parts by weight, phenol novolak resin as a curing agent for the epoxy resin (Dainippon Ink Chemical Industry Co., Ltd.) Product name Plyofen LF28
Phenoxy resin (molecular weight: 50,000; trade name: Phenotote YP-50 manufactured by Toto Kasei Co., Ltd.) as a high-molecular weight resin having a weight-average molecular weight of 30,000 or more, which is 40 parts by weight, is compatible with the epoxy resin. 40 parts by weight, epoxy group-containing acrylic rubber as epoxy group-containing acrylic polymer (molecular weight 1,000,000, Tg-7 ° C, glycidyl methacrylate 1% by weight, trade name HT manufactured by Teikoku Chemical Industry Co., Ltd.)
200 parts by weight of R-860P-3DR (C)), and 1-cyanoethyl-2-phenylimidazole (Curesol 2P manufactured by Shikoku Chemicals Co., Ltd.) as a curing accelerator
0.5 parts by weight of silica (using Z-CN) and silica (using SO-25R manufactured by Tatsumori Co., Ltd.) as an inorganic filler 62
Parts by weight (equivalent to 10% by volume), γ-glycidoxypropyltrimethoxysilane as a silane coupling agent (NUC A-187 manufactured by Nippon Unicar Co., Ltd. is used)
To a composition consisting of 0.7 parts by weight, methyl ethyl ketone was added, mixed with stirring, and further kneaded using a bead mill,
Vacuum degassed. The adhesive varnish was applied on a release-treated polyethylene terephthalate film having a thickness of 75 μm, and dried by heating at 140 ° C. for 5 minutes to form a coating film having a thickness of 80 μm, thereby producing an adhesive film. This adhesive film was cured by heating at 170 ° C. for 1 hour, and its storage elastic modulus was measured by a dynamic viscoelasticity measuring device (DVE-V4, manufactured by Rheology Co., Ltd.).
(Sample size: length 20mm, width 4m)
m, film thickness 80 μm, heating rate 5 ° C./min, tensile mode,
(10Hz, automatic static load), 400MP at 25 ° C
a, 5 MPa at 260 ° C. The solid content of the adhesive varnish was 28% by weight.

(Adhesive Varnish 4) Bisphenol A type epoxy resin (epoxy equivalent: 190,
Yuka Shell Epoxy Co., Ltd. Epicoat 828
45 parts by weight, 15 parts by weight of cresol novolak type epoxy resin (epoxy equivalent: 195, trade name: ESCN195 manufactured by Sumitomo Chemical Co., Ltd.), phenol novolak resin (Dainippon Ink and Chemicals, Inc.) as a curing agent for epoxy resin Product name Plyofen LF28
Phenoxy resin (molecular weight: 50,000; trade name: Phenotote YP-50 manufactured by Toto Kasei Co., Ltd.) as a high-molecular weight resin having a weight-average molecular weight of 30,000 or more, which is 40 parts by weight, is compatible with the epoxy resin. 15 parts by weight, an epoxy group-containing acrylic rubber as an epoxy group-containing acrylic polymer (molecular weight 1,000,000, Tg-7 ° C, glycidyl methacrylate 3% by weight, HTR- manufactured by Teikoku Chemical Industry Co., Ltd.)
860P-3DR) 150 parts by weight, 1-cyanoethyl-2-phenylimidazole as a curing accelerator (Curesol 2PZ-CN manufactured by Shikoku Chemicals Co., Ltd.) 0.5 part by weight, γ as a silane coupling agent −
Glycidoxypropyltrimethoxysilane (using NUC A-187 manufactured by Nippon Unicar Co., Ltd.) 0.7
To the composition consisting of parts by weight, methyl ethyl ketone was added, mixed with stirring, and degassed under vacuum. The adhesive varnish was applied on a release-treated polyethylene terephthalate film having a thickness of 75 μm, and dried by heating at 140 ° C. for 5 minutes to form a coating film having a thickness of 80 μm, thereby producing an adhesive film. The adhesive film was cured by heating at 170 ° C. for 1 hour, and its storage elastic modulus was measured by a dynamic viscoelasticity measuring device (Dr.
E-V4) (sample size: length 20 m)
m, width 4 mm, film thickness 80 μm, heating rate 5 ° C./min, tensile mode, 10 Hz, automatic static load). As a result, it was 360 MPa at 25 ° C. and 4 MPa at 260 ° C. The solid content of the adhesive varnish was 22% by weight.

(Adhesive Varnish 5) As an epoxy resin, bisphenol A type epoxy resin (epoxy equivalent 190,
Yuka Shell Epoxy Co., Ltd. Epicoat 828
45 parts by weight, 15 parts by weight of cresol novolak type epoxy resin (epoxy equivalent: 195, trade name: ESCN195 manufactured by Sumitomo Chemical Co., Ltd.), phenol novolak resin (Dainippon Ink and Chemicals, Inc.) as a curing agent for epoxy resin Product name Plyofen LF28
Phenoxy resin (molecular weight: 50,000; trade name: Phenotote YP-50 manufactured by Toto Kasei Co., Ltd.) as a high-molecular weight resin having a weight-average molecular weight of 30,000 or more, which is 40 parts by weight, is compatible with the epoxy resin. 15 parts by weight, an acrylic rubber containing no epoxy group having a composition obtained by removing glycidyl methacrylate from an epoxy group-containing acrylic rubber (molecular weight: 1,000,000, glycidyl methacrylate: 0% by weight, HTR-860P-3DR (A) manufactured by Teikoku Chemical Industry Co., Ltd.) 100 parts by weight, 1-cyanoethyl-2-phenylimidazole as a curing accelerator (Curesol 2PZ-CN manufactured by Shikoku Chemicals Co., Ltd.) 0.5 part by weight, and γ-glycid as a silane coupling agent Xypropyl trimethoxysilane (product name NUC A-187 manufactured by Nippon Unicar Co., Ltd. A composition consisting of use) 0.7 parts by weight, and mixed by stirring methyl ethyl ketone and vacuum degassed. The adhesive varnish was applied on a release-treated polyethylene terephthalate film having a thickness of 75 μm, and dried by heating at 140 ° C. for 5 minutes to form a coating film having a thickness of 80 μm, thereby producing an adhesive film. The adhesive film was cured by heating at 170 ° C. for 1 hour, and its storage modulus was measured using a dynamic viscoelasticity measuring device (DVE-V4, manufactured by Rheology) (sample size: length 20 mm, width 4 m).
m, film thickness 80 μm, heating rate 5 ° C./min, tensile mode,
(10Hz, automatic static load), 400MP at 25 ° C
a, 1 MPa at 260 ° C. The solid content of the adhesive varnish was 28% by weight.

Example 1 An adhesive varnish 1 was coated with a thickness of 75
It was applied on a polyethylene terephthalate film having a release treatment of μm and dried by heating at 140 ° C. for 5 minutes to form a B-stage coating film having a thickness of 75 μm, thereby producing an adhesive film provided with a carrier film. This adhesive film was heated at a temperature of 110 ° C., a pressure of 0.3 MPa, and a speed of 0.3 m.
At a rate of / min, the substrates were bonded using a hot roll laminator to produce a single-layer film-shaped adhesive member having a thickness of 150 μm. The curing degree of the adhesive in this state was determined by DSC
As a result of measurement (temperature rise rate, 10 ° C./min) using (DuPont 912 type DSC), heat generation of 20% of the total curing calorific value was completed. The amount of the solvent remaining only in the adhesive is 1.
It was 5% by weight.

Example 2 An adhesive member in the form of a single-layer film was prepared in the same manner as in Example 1 except that the adhesive varnish 1 was changed to the adhesive varnish 2. The degree of curing of the adhesive in this state was measured using a DSC (a 912 type DSC manufactured by DuPont) (heating rate, 10 ° C./min), and as a result, heat generation of 20% of the total curing calorific value was completed. Condition. The residual solvent amount was 1.4% by weight.

Example 3 A single-layer film-shaped adhesive member was produced in the same manner as in Example 1 except that the adhesive varnish 1 was changed to the adhesive varnish 3. The degree of curing of the adhesive in this state was measured using a DSC (a 912 type DSC manufactured by DuPont) (heating rate, 10 ° C./min), and as a result, heat generation of 20% of the total curing calorific value was completed. Condition. The residual solvent amount was 1.6% by weight.

Example 4 The adhesive varnish 2 was coated with a thickness of 25
μm polyimide film (Ube Industries, Ltd., trade name: Upilex SGA-25)
Heat drying at 0 ° C. for 5 minutes to form a coating film in a B-stage state having a film thickness of 50 μm, further apply the same varnish to the opposite surface on which the adhesive layer was formed, and heat dry at 140 ° C. for 5 minutes. Forming a B-stage coating film having a thickness of 70 μm,
An adhesive member having adhesive layers on both surfaces of a polyimide film used as a core material was produced. The curing degree of the adhesive in this state was measured by DSC (912 type DSC manufactured by DuPont).
As a result of measurement (heating rate, 10 ° C./min) using
The heat generation of 25% of the total curing heat generation was completed in the μm layer, and the heat generation of 20% of the total curing heat generation was completed in the 75 μm layer. The residual solvent amount was 1.3 to 1.5% by weight in each case.

Example 5 An adhesive varnish 2 was coated to a thickness of 75
It was applied on a polyethylene terephthalate film having a release treatment of μm and dried by heating at 140 ° C. for 5 minutes to form a B-stage coating film having a thickness of 75 μm, thereby producing an adhesive film provided with a carrier film. A 25 μm thick polyimide film (using UPILEX SGA-25 manufactured by Ube Industries, Ltd.)
110 ° C, pressure 0.3MPa, speed 0.2 on both sides of
Attachment was performed using a hot roll laminator under the condition of m / min to prepare an adhesive member having an adhesive layer on both surfaces of a polyimide film used as a core material. The degree of cure of the adhesive in this state was measured using a DSC (DuPont 912 type D).
SC) (heating rate, 10 ° C./min), the adhesive layers on both sides were in a state where heat generation of 20% of the total curing heat generation was finished. The residual solvent amount was 1.4% by weight.

Example 6 A core material was prepared in the same manner as in Example 5, except that the polyimide film of the core material was a liquid crystal polymer film having a thickness of 25 μm (Vectra LCP-A manufactured by Kuraray Co., Ltd.). An adhesive member having an adhesive layer on both sides of the used liquid crystal polymer film was produced. The curing degree of the adhesive in this state was measured using a DSC (a 912 type DSC manufactured by DuPont) (heating rate, 10 ° C. /
Minutes), the total amount of heat generated by curing on both adhesive layers was 2
It was in a state where heat generation of 0% was finished. The amount of the remaining solvent was 1.
It was 4% by weight.

Example 7 A polyimide film as a core material was formed from a 25 μm-thick tetrafluoroethylene-hexafluoropropylene copolymer film (trade name: Teflon FEP manufactured by DuPont-Mitsui Fluorochemicals Co., Ltd.)
An adhesive member having an adhesive layer on both surfaces of a tetrafluoroethylene-hexafluoropropylene copolymer film was produced in the same manner as in Example 5 except that the above procedure was adopted. As the tetrafluoroethylene-hexafluoropropylene copolymer film, a film having both surfaces chemically treated (trade name, manufactured by Junko Co., Ltd.) was used in order to improve wettability and increase adhesiveness. The degree of cure of the adhesive in this state was determined by DSC (912 manufactured by DuPont).
As a result of measurement (temperature rise rate, 10 ° C./min), the adhesive layers on both surfaces were in a state where heat generation of 20% of the total curing heat generation was finished. Residual solvent amount is 1.4% by weight
Met.

Example 8 An adhesive varnish 2 was coated to a thickness of 75
Coating on μm-released polyethylene terephthalate film, heating and drying at 140 ° C. for 5 minutes to form a B-stage coating film with a thickness of 60 μm, and a single-layer film-like adhesive with a carrier film A member was manufactured.
This single-layer film is formed on both sides of a porous polytetrafluoroethylene film having a thickness of 100 μm (trade name: Poeflon WP-100-100 manufactured by Sumitomo Electric Industries, Ltd.) at a temperature of 110 ° C., a pressure of 0.3 MPa, and a speed of 0.1 μm. 2m /
A hot roll laminator was applied under the same conditions as in Example 1 to prepare an adhesive member having an adhesive layer on both sides of a porous polytetrafluoroethylene film used as a core material. The curing degree of the adhesive in this state was measured using a DSC (a 912 type DSC manufactured by DuPont) (temperature rising rate,
(10 ° C./min), the adhesive layers on both sides were in a state where heat generation of 20% of the total curing heat generation was finished. The amount of the remaining solvent was 1.3% by weight.

Comparative Example 1 A single-layer film-shaped adhesive member was produced in the same manner as in Example 1 except that the adhesive varnish 1 was changed to the adhesive varnish 4. The degree of curing of the adhesive in this state was measured using a DSC (a 912 type DSC manufactured by DuPont) (heating rate, 10 ° C./min), and as a result, heat generation of 20% of the total curing calorific value was completed. Condition.

Comparative Example 2 A single-layer film-shaped adhesive member was produced in the same manner as in Example 1 except that the adhesive varnish 1 was changed to the adhesive varnish 5. The degree of curing of the adhesive in this state was measured using a DSC (a 912 type DSC manufactured by DuPont) (heating rate, 10 ° C./min), and as a result, heat generation of 20% of the total curing calorific value was completed. Condition.

Reference Example 1 A single-layer film-shaped adhesive member provided with a carrier film was produced in the same manner as in Example 1 except that the drying conditions were changed from 140 ° C. for 5 minutes to 160 ° C. for 10 minutes. The degree of cure of the adhesive in this state is D
As a result of measurement (heating rate, 10 ° C./min) using SC (912 type DSC manufactured by DuPont), 50% of the total curing calorific value was obtained.
Was in a state where heat generation was finished. The residual solvent amount was 1.0% by weight.

By using the obtained adhesive member, FIG.
(D) A semiconductor device sample (a solder ball is formed on one side) in which a semiconductor chip and a wiring substrate using a polyimide film having a thickness of 25 μm as a base material are bonded together with an adhesive member as shown in FIG. Properties and moisture resistance were examined. As a method for evaluating heat resistance, a reflow crack resistance and a temperature cycle test were applied. The reflow crack resistance was evaluated by repeating the process of 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 cooling it by leaving it at room temperature twice. The cracks in the sample were visually observed and observed with an ultrasonic microscope. If there is no crack, mark ○.
What occurred was rated as x. The temperature cycling resistance was determined by leaving the sample in a -55 ° C atmosphere for 30 minutes,
The process of leaving the substrate in an atmosphere at 5 ° C. for 30 minutes was defined as one cycle, and after 1000 cycles, an ultrasonic microscope was used. The moisture resistance was evaluated at a temperature of 12
The test was performed by observing peeling after treatment for 72 hours in an atmosphere of 1 ° C., 100% humidity, and 2 atmospheres (pressure cooker test: PCT treatment). When the peeling of the adhesive member was not recognized, it was evaluated as ○, and when peeled, it was evaluated as ×.
The production efficiency was such that the solid content of the adhesive varnish was 25% by weight.
Was exceeded, and x was 25 wt% or less.
Table 1 shows the results.

[0054]

[Table 1] Evaluation item Example 1 2 3 4 5 6 7 8 Heat resistance Reflow crack resistance ○ ○ ○ ○ ○ ○ ○ ○ Temperature cycle ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Manufacturing efficiency ○ ○ ○ ○ ○ ○ ○ ○ Evaluation item Comparative example Reference example 1 2 1 Heat resistance Resistance to reflow crack ○ × × Temperature cycle resistance ○ × × Moisture resistance ○ ○ × Manufacturing efficiency × ○ ○

In Examples 1 and 3, adhesion using an epoxy resin and its curing agent, an epoxy group-containing acrylic copolymer, a curing accelerator, and an adhesive containing both a high molecular weight resin compatible with the epoxy resin was used. Example 2 and Examples 4 to 8 are adhesive members using an adhesive containing both an epoxy resin and its curing agent, an epoxy group-containing acrylic copolymer, and a curing accelerator. The cured product shows a storage elastic modulus at 25 ° C. and 260 ° C. which is specified as preferable in the present invention. Semiconductor devices using these adhesive members had good reflow crack resistance, temperature cycle resistance, and moisture resistance. Examples 4 to 8 were adhesive members provided with a core material, but had good handleability. Comparative Example 1 uses an epoxy group-containing acrylic copolymer containing 3% by weight of glycidyl methacrylate, so it has excellent reliability such as heat resistance and moisture resistance, but has a low varnish solids concentration and produces a large amount of varnish. Production efficiency was poor. In Comparative Example 2, since an acrylic copolymer containing no epoxy group was used, the storage elastic modulus at a high temperature was low, and the heat resistance was poor. Reference Example 1 shows that the adhesive has exceeded 10% to 40% of the total curing calorific value and has completed 50% of the total curing calorific value, as measured by DSC defined as preferred in the present invention. In this state, circuit filling and adhesion are poor, and heat resistance and moisture resistance are poor.

[0056]

As described above, since the adhesive member using the adhesive of the present invention has a low elastic modulus near room temperature,
In a semiconductor device in which a semiconductor chip and a wiring board are bonded by this bonding member, thermal stress generated during heating and cooling can be reduced due to a difference in thermal expansion coefficient between the semiconductor chip and the wiring board. Therefore, cracks are not generated during reflow, and destruction is not observed even after the temperature cycle test, and the heat resistance is excellent. Further, since the solid content of the varnish can be increased, the production efficiency is high. With these effects, it is possible to efficiently provide an adhesive material necessary for a semiconductor device exhibiting excellent reliability.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view showing a film-like adhesive member comprising a single layer of an adhesive according to the present invention, and FIG. 1B is a cross-sectional view showing an adhesive member having an adhesive on both sides of a core material according to the present invention. .

FIG. 2A is a cross-sectional view showing a wiring board for mounting a semiconductor using a film-like adhesive member composed of an adhesive single layer according to the present invention, and FIG. 2B is a sectional view showing an adhesive on both sides of a core material according to the present invention. Sectional drawing which shows the wiring board for semiconductor mounting using the provided adhesive member.

FIG. 3 (a) shows that a semiconductor chip and a wiring board are bonded using a film-like bonding member composed of an adhesive single layer according to the present invention, and pads of the semiconductor chip and wiring on the board are connected by bonding wires. Sectional view of a semiconductor device,
(B) shows a semiconductor device in which a semiconductor chip and a wiring board are adhered by using an adhesive member provided with an adhesive on both sides of a core material according to the present invention, and pads of the semiconductor chip and wiring on the board are connected by bonding wires. FIG. 4C is a cross-sectional view of a semiconductor device in which a semiconductor chip and a wiring substrate are bonded using a film-like bonding member made of a single layer of an adhesive according to the present invention, and inner leads of the substrate are bonded to pads of the semiconductor chip. And (d) is a cross-sectional view of a semiconductor device in which a semiconductor chip and a wiring board are adhered to each other using an adhesive member provided with an adhesive on both sides of a core material according to the present invention, and inner leads of the substrate are bonded to pads of the semiconductor chip.

[Explanation of reference numerals] Adhesive 2. 2. Core material (heat-resistant thermoplastic film) Wiring 4. Wiring board 5. Semiconductor chip 6. Bonding wire 6 '. Inner lead 7. Sealing material 8. External connection terminal

Continuing on the front page (72) Inventor Yuko Tanaka 1500 Oji Ogawa, Shimodate City, Ibaraki Pref.Hitachi Chemical Industry Co., Ltd. (72) Inventor Yasushi Jindai 1500 Oji Ogawa, Shimodate City, Ibaraki Prefecture Inside Shimodate Research Laboratory, Hitachi Chemical Co., Ltd. 4J040 CA002 EB031 EB032 EC001 EC002 EC071 EC232 EE062 HA136 HA306 HC24 HD35 HD36 HD37 JA09 KA16 KA17 KA42 LA01 LA02 LA06 LA07 LA08 MA10 NA20 5F047 BA23 BA34 BB11 BB16

Claims (20)

[Claims] (1) Epoxy resin and its curing agent 10
0 parts by weight, (2) 5 to 40 parts by weight of a high molecular weight resin compatible with the epoxy resin and having a weight average molecular weight of 30,000 or more;
(3) An epoxy group-containing acrylic copolymer having a Tg (glass transition temperature) of -10 ° C or more and a weight average molecular weight of 800,000 or more containing 0.5 to 2% by weight of glycidyl (meth) acrylate. (4) An adhesive containing 0.1 to 5 parts by weight of a curing accelerator. (1) Epoxy resin and its curing agent 10
0 parts by weight, (2) glycidyl (meth) acrylate
Tg (glass transition temperature) containing 5-2% by weight is -10C
(3) 75 to 200 parts by weight of an epoxy group-containing acrylic copolymer having a weight average molecular weight of 800,000 or more,
An adhesive containing 0.1 to 5 parts by weight of a curing accelerator. (1) 100 parts by weight of an epoxy resin and a phenol resin, (2) 5 to 40 parts by weight of a phenoxy resin,
(3) An epoxy group-containing acrylic copolymer having a Tg (glass transition temperature) of -10 ° C or more and a weight average molecular weight of 800,000 or more containing 0.5 to 2% by weight of glycidyl (meth) acrylate. (4) An adhesive containing 0.1 to 5 parts by weight of a curing accelerator. 4. Tg (glass transition temperature) containing (1) 100 parts by weight of an epoxy resin and a phenol resin, and (2) 0.5 to 2% by weight of glycidyl (meth) acrylate is -1.
75 to 200 parts by weight of an epoxy group-containing acrylic copolymer having a temperature of 0 ° C. or more and a weight average molecular weight of 800,000 or more,
(3) An adhesive containing 0.1 to 5 parts by weight of a curing accelerator. 5. The adhesive according to claim 1, comprising 1 to 20 parts by volume of the inorganic filler based on 100 parts by volume of the adhesive resin. 6. The inorganic filler is any one of alumina, silica, aluminum hydroxide and antimony oxide.
The adhesive according to item 1. 7. The adhesive according to claim 1, wherein the adhesive has been heated to 10 to 40% of the total curing calorific value when measured using DSC. 8. The adhesive according to claim 1, wherein the amount of the residual solvent is 5% by weight or less. 9. The cured adhesive has a storage elastic modulus of from 20 to 2.0 at 25 ° C. as measured using a dynamic viscoelasticity measuring device.
The adhesive according to any one of claims 1 to 8, wherein the adhesive is 00 MPa and 3 to 50 MPa at 260 ° C. 10. A film-like adhesive member obtained by forming the adhesive according to claim 1 on a carrier film. 11. An adhesive member obtained by forming the adhesive according to claim 1 on both surfaces of a core material. 12. The adhesive member according to claim 11, wherein the core material is a heat-resistant thermoplastic film. 13. The adhesive member according to claim 12, wherein the heat-resistant thermoplastic film material has a softening point temperature of 260 ° C. or higher. 14. The adhesive member according to claim 11, wherein the core material or the heat-resistant thermoplastic film is a porous film. 15. The adhesive member according to claim 12, wherein the heat-resistant thermoplastic film is a liquid crystal polymer. 16. The adhesive member according to claim 12, wherein the heat-resistant thermoplastic film is any of polyamide imide, polyimide, polyether imide and polyether sulfone. 17. The heat-resistant thermoplastic film is any one of polytetrafluoroethylene, ethylene tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and tetrafluoroethylene-perfluoroalkylvinyl ether copolymer. Item 15. The adhesive member according to any one of Items 14. 18. A wiring board for mounting a semiconductor, comprising the adhesive member according to claim 10 on a semiconductor chip mounting surface of the wiring board. 19. The semiconductor chip and the wiring board according to claim 10.
A semiconductor device bonded using the bonding member according to claim 17. 20. A semiconductor device wherein a semiconductor chip having an area of at least 70% of an area of a wiring board and a wiring board are bonded by using the bonding member according to claim 10. .