JP2012044193A - Adhesive sheet for semiconductor device, component for semiconductor device and semiconductor device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To commercially provide an adhesive sheet for a semiconductor device that has excellent processability, reflow heat resistance and thermal cycle resistance, and to provide a component for the semiconductor device and the semiconductor device using the same.SOLUTION: The adhesive sheet for the semiconductor device has a light peel protection film, an adhesive layer and a heavy peel protection film laminated in this order. In the adhesive sheet for the semiconductor device, the difference in peeling force relative to the adhesive layer between the light peel protection film and the heavy peel protection film is 5 N/m or more, the elongation of the heavy peel protection film in a temperature range from 60 to 130°C is 700% or more and 2,000% or less, and the peeling force of the heavy peel protection film with respect to the adhesive layer is 3 N/m or more and 70 N/m or less after it is heated at a temperature of 130°C for five minutes.

Description

  The present invention relates to an adhesive sheet for a semiconductor device, a component for a semiconductor device, and a semiconductor device that are preferably used when a semiconductor integrated circuit (IC) is mounted and packaged.

  Conventionally, package forms such as a dual inline package (DIP), a small outline package (SOP), and a quad flat package (QFP) have been used as semiconductor integrated circuit (IC) packages. However, with the increase in the number of pins of ICs and the downsizing of packages, the QFP package that can increase the number of pins is approaching the limit. Therefore, in recent years, BGA (Ball Grid Array), LGA (Land Grid Array), PGA (Pin Grid Array), etc. have been put to practical use as means for increasing the number of pins and reducing the size. Among them, the BGA method is attracting attention because of the high possibility of cost reduction, weight reduction, and thickness reduction by using plastic materials.

  FIG. 1 shows one mode of a semiconductor device by a BGA method using an adhesive sheet for a semiconductor device. In FIG. 1, a wiring board layer composed of an insulating layer 3 and a semiconductor integrated circuit connecting conductor 5, an adhesive layer 4 constituting the wiring board layer, a reinforcing plate (stiffener), and heat dissipation for connecting a semiconductor integrated circuit 1. It has at least one or more adhesive layers 6 for laminating these, such as a plate (heat spreader), a shield plate, and the like, and a gold bump 2 and a solder resist. 8 and having a solder ball 9 in a grid (grid array) as an external connection portion of a semiconductor integrated circuit connection substrate to which the semiconductor integrated circuit 1 is connected. The semiconductor device is sealed with a sealing resin 10.

  The BGA method is characterized in that a solder ball substantially corresponding to the number of pins of an IC is provided on a grid (grid array) as an external connection portion of a semiconductor connection substrate to which the IC is connected. Connection to the printed circuit board (mother board) is performed by placing the solder balls so as to coincide with the conductor pattern of the printed circuit board on which the solder has already been printed, and melting the solder by reflow. The biggest feature is that since the bottom surface of the interposer can be used, many terminals can be arranged in a small space compared to a package such as QFP that can only be used at the periphery. For this reason, in terms of mounting, it is possible to reduce the mounting area and increase the mounting efficiency. As a further advancement of this miniaturization function, there is a chip scale package (CSP), a micro BGA (μ-BGA), a fine pitch BGA (FP-BGA), a memory BGA (m-BGA), and a board on chip (BOC). ) Etc. have been proposed.

  On the other hand, in the BGA method, a method of laminating a metal plate or the like on a semiconductor connection substrate is generally used for the purpose of reinforcement, heat dissipation, and electromagnetic shielding. In particular, it is effective when a TAB tape, a flexible printed board, or a rigid board is used for a wiring board made of an insulating layer for connecting an IC and a conductor for connecting a semiconductor integrated circuit. For this reason, the semiconductor connection substrate is formed with a conductor pattern such as an insulating layer for connecting an IC and a wiring substrate layer composed of a conductor for connecting a semiconductor integrated circuit, a reinforcing plate (stiffener) or a heat radiating plate (heat spreader). It is the structure which has at least 1 layer each of the layer which is not made and the adhesive bond layer for laminating these. An IC chip is mounted on these semiconductor connection substrates, and the semiconductor element and metal wiring are connected by wire bonding or inner leads. Thereafter, resin sealing is performed, and the semiconductor device sealed with resin is coated with a solder paste and mounted with solder balls.

  Eventually, the adhesive layer remains in the package. Therefore, the properties required for the adhesive layer are (a) reflow heat resistance, (b) absorbability of stress generated during thermal cycling and reflow between different materials such as a wiring board layer and a reinforcing plate (stress (Relaxability), (c) easy processability, and (d) insulation properties when laminated on the wiring.

  Easy processability is a characteristic required not only to improve yield but also to improve reflow resistance and various reliability. It is necessary to suppress the inclusion of foreign substances and bubbles that generate and accumulate moisture between the adhesive layer and the adherend such as a metal plate or a wiring board, and low defects and short-time workability are required. In particular, in the bonding process between the adhesive sheet for semiconductor devices and the adherend, it is important to prevent defects such as bonded bubbles. From such a point of view, conventionally, a structure having a protective film layer on one side or both sides of an adhesive layer suppresses foreign matters, bonded bubbles, exudation / sagging of the adhesive, and the like for semiconductor devices with improved flatness. Adhesive sheets have been proposed (see Patent Documents 1 to 4). In a configuration having a protective film on one side, and in a configuration having a protective film on both sides, a light release protective film which is a protective film on one side is peeled off, and the adherend is applied by a laminating method or a press method. And pasted together.

JP 2003-183606 A JP 2002-180017 A Japanese Patent Laid-Open No. 11-220051 JP-A-7-7048

  However, in these adhesive sheets for semiconductor devices improved by various conventional methods, since the thermal stability in the drying process after coating of the protective film has been regarded as important, a protective film having a high melting point has been used. . However, these protective films have a low tensile elongation at a bonding temperature of 60 ° C. to 130 ° C., so that the protective film does not follow the deformation of the wiring pattern or the height of the parts during the bonding process, and uneven bonding is caused. As a result, there has been a problem in that bonded bubbles are generated between the adhesive layer and the adherend. Such bonded bubbles between the adhesive layer and the adherend cause cracks in the heat curing process, the reflow process, and the thermal cycle. Moreover, the peeling force after the heating of the heavy peeling protective film which is a protective film of the other surface is also important in a heating process. If the peel strength after heat curing is small, the protective film may be displaced or peeled off, resulting in a problem that bonded air bubbles are generated. Moreover, when the peeling force after heat-curing is too large, damage to the adhesive layer, a decrease in yield, or the like becomes a problem.

  Accordingly, an object of the present invention is to improve the yield in the processing step by eliminating the problems that occur in the processing step, and further to have excellent reliability such as reflow heat resistance and thermal cycle resistance. To provide a sheet, and to provide a semiconductor device component and a semiconductor device using the adhesive sheet for the semiconductor device.

  That is, the adhesive sheet for a semiconductor device of the present invention is an adhesive sheet for a semiconductor device in which a light release protective film, an adhesive layer, and a heavy release protective film are laminated in this order, The peeling force difference with respect to the adhesive layer of the heavy release protective film is 5 N / m or more, and the elongation in the temperature range of 60 ° C. to 130 ° C. of the heavy release protective film is 700% or more and 2,000% or less, And the peeling force with respect to this adhesive bond layer after heating the temperature of 130 degreeC of this heavy peeling protective film for 5 minutes is 3 N / m or more and 70 N / m or less, The adhesive sheet for semiconductor devices characterized by the above-mentioned.

  Moreover, in this invention, melting | fusing point of the said heavy peeling protective film is 130 degreeC or more, and the elongation of the adhesive bond layer in the temperature range of 60 to 130 degreeC is 300% or more and 2000% or less. Is included as a preferred embodiment.

  Moreover, in this invention, said adhesive sheet for semiconductor devices can be applied to the components for semiconductor devices, and a semiconductor device.

  ADVANTAGE OF THE INVENTION According to this invention, the adhesive sheet for semiconductor devices excellent in workability is obtained, hold | maintaining outstanding reflow heat resistance and thermal cycle resistance, This adhesive sheet for semiconductor devices is suitable for manufacture of a semiconductor device. Used for.

FIG. 1 is a cross-sectional view showing an embodiment of a BGA type semiconductor device using an adhesive sheet for a semiconductor device. FIG. 2 is a schematic cross-sectional view showing one embodiment of the adhesive sheet for a semiconductor device of the present invention. FIG. 3 is a schematic cross-sectional view showing one embodiment of the semiconductor connection substrate of the present invention.

  As a result of intensive studies on the physical properties of the protective film in order to achieve the above object, the present inventors have reached the present invention, and the tensile elongation in the tensile test in the temperature range from 60 ° C. to 130 ° C. Is 700% or more and 2000% or less, and the peeling force for the adhesive layer (A) after heating for 5 minutes at a temperature of 130 ° C. is 3 N / m or more and 70 N / m or less. It has been found that an adhesive sheet for a semiconductor device excellent in processability can be obtained while maintaining excellent reflow heat resistance and thermal resistance by using a release protective film.

  Hereinafter, the adhesive sheet for semiconductor devices of the present invention will be described in detail. The adhesive sheet for a semiconductor device of the present invention is an adhesive sheet for a semiconductor device having a protective film (light release protective film; CF1, heavy release protective film; CF2) on both surfaces of the adhesive layer, that is, a light release protective film ( CF1), an adhesive layer for a semiconductor device, and an adhesive layer and a heavy release protective film (CF2) laminated in this order, both of the light release protective film (CF1) and the heavy release protective film (CF2) The difference in peel force between the protective film and the adhesive layer (A) is 5 N / m or more, and the tensile elongation of the heavy peel protective film (CF2) in the tensile test in the temperature range of 60 ° C. to 130 ° C. is 700%. The peel strength for the adhesive layer (A) after heating for 5 minutes at the temperature of the heavy peel protective film 130 ° C. is 2000 N or less and 3 N / m. Furthermore, an adhesive sheet for a semiconductor device which is characterized in that not more than 70N / m.

  The protective film used in the present invention is not particularly limited as long as it can be peeled without impairing the form and function of the adhesive layer, but for the production process of the adhesive sheet for semiconductor devices, and further thereafter Because of the process of attaching to the adherend, this can be classified by function.

  That is, the protective film used in the present invention is a protective film used as a base material for applying a paint (adhesive) mainly when producing an adhesive sheet for a semiconductor device. The film is called a light release protective film (CF1)) and a protective film (mainly laminated to prevent adhesion of foreign matters etc. to the formed adhesive layer (A) which has been dried after coating with a paint) In the present invention, this protective film can be classified as a heavy release protective film (CF2).

  The light release protective film (CF1) used in the present invention is usually required to have heat resistance. The light release protective film is usually dried at a temperature of 120 ° C. to 180 ° C. in the drying process after the paint as an adhesive is applied. The heat resistance referred to here is the heat resistance in the drying process. . Therefore, as the light release protective film, those having small deformation and heat shrinkage in this temperature range are preferable, and various preferably stretched films suitable for the light release protective film are usually used. Furthermore, as the light release protective film, a film in which the internal stress of the film to which heat equal to or higher than the drying temperature is applied before application of the adhesive is preferably used.

  That is, the light release protective film preferably has a tensile elongation by a tensile test in a temperature range of 60 to 130 ° C. of 500% or less, more preferably 400% or less, and further preferably 300% or less. Moreover, it is preferable that the heat-shrink rate at the temperature of 150 degreeC is 20% or less, More preferably, it is 15% or less, More preferably, it is 10% or less.

  The tensile elongation, heat shrinkage ratio, and the like can be changed depending on the ratio of aliphatic hydrocarbons to aromatic hydrocarbons, the length of the aliphatic hydrocarbons, and the degree of crystallinity depending on the degree of stretching.

  Specific examples of such a light release protective film include, for example, polyester, polyolefin, polyamide, polyphenylene sulfide, polyvinyl chloride, polytetrafluoroethylene, polyvinyl fluoride, polyvinyl butyrate, polyvinyl acetate, polyvinyl alcohol, polycarbonate, Examples thereof include plastic films such as polyimide and polymethyl methacrylate, and films obtained by coating the plastic films with a release agent such as silicone, alkyd resin, polyolefin resin, or fluorine-containing compound.

  Among these light-release protective films, polyester films that have been subjected to a release treatment with a release agent of silicone or fluorine-containing compound that allows easy adjustment of the release force are superior in terms of heat resistance and surface smoothness. And is particularly preferably used. In addition, the light release protective film may be colored with a pigment so as to have good visibility during processing. The thickness of the light release protective film varies depending on the deformation rate and heat shrinkage rate of the film used at a high temperature, but is usually preferably in the range of 10 to 100 μm, more preferably 25 μm or more, and further preferably 35 μm. That's it.

  On the other hand, it is important that the heavy peel protective film (CF2) used in the present invention has a tensile elongation of 700% or more and 2000% or less by a tensile test in a temperature range of 60 ° C to 130 ° C. A film is preferably used. If the tensile elongation is less than 700%, the amount of deformation of the heavy release protective film is small, so that the embedding property of the adhesive layer in the wiring pattern and parts is impaired. On the other hand, when the elongation at break is larger than 2,000%, handling in the process is impaired, which is not preferable.

  Since the heavy release protective film is laminated for the purpose of protecting the dried adhesive layer (A) from adhesion of foreign matter, etc., heat resistance is not required as with the light release protective film (CF2). After being peeled off, it is attached to the adherend by a lamination method or a press method at a temperature of 60 ° C. to 130 ° C. Therefore, the heavy release protective film is preferably 130 ° C. or higher, more preferably 150 ° C. or higher, A film having a melting point of 170 ° C. or higher is desired.

  Specific examples of the heavy release protective film include, for example, unstretched polyester, high-density polyethylene (stretched / unstretched), unstretched polyamide, unstretched polyphenylene sulfide, unstretched polyvinyl chloride, unstretched polytetrafluoroethylene, and unstretched. Examples include unstretched films made of polyvinyl fluoride, unstretched polyvinyl butyrate, unstretched polyvinyl acetate, unstretched polyvinyl alcohol, and the like. A film obtained by coating the unstretched film with a release agent such as silicone, alkyd resin, polyolefin resin, or fluorine-containing compound is preferably used. Among these films, an unstretched polypropylene film that has been subjected to a release treatment and a nonstretched olefin film such as high-density polyethylene in terms of the tensile elongation in a tensile test in a temperature range of 60 ° C. to 130 ° C. Is particularly preferably used.

  The thickness of the heavy release protective film is usually preferably in the range of 5 to 75 μm, more preferably 5 to 50 μm, and still more preferably 10 to 35 μm.

  In this invention, when the peeling force with respect to the adhesive bond layer (A) of a light peeling protective film (CF1) and a heavy peeling protective film (CF2) is set to F1 and F2, respectively, those peeling force difference (F2-F1) is It is important that it is 5 N / m or more.

  When the peel force difference is smaller than 5 N / m, it is not stable which protective film side the peeled surface of the adhesive layer (A) is on, which causes a problem in use. Moreover, it is preferable that peeling force (F1) is 1 N / m or more and 100 N / m or less, and peeling force (F2) is 5 N / m or more and 100 N / m or less. When the peeling force (F1) is less than 1 N / m, the protective film is removed, and when it is more than 100 N / m, peeling is difficult, which is not preferable. Further, when the peeling force (F2) is less than 5 N / m, an appropriate difference in peeling force cannot be obtained, so that the peeling surface is not stable, and when it is more than 100 N / m, peeling becomes difficult, which is not preferable.

  Furthermore, since the heavy release protective film (CF2) is peeled off after the adhesive layer (A) is attached to the adherend by laminating or pressing at a temperature of 60 ° C. to 130 ° C., the peel strength after heating Is important, and the peel force (F2 ′) after heating at 130 ° C. for 5 minutes is preferably 3 N / m or more and 70 N / m or less. If it is less than 3 N / m, the heavy release protective film may fall off, and if it is more than 70 N / m, peeling may be difficult.

  The adhesive composition that constitutes the adhesive layer of the present invention is more preferable in terms of reflow resistance in that it contains at least one kind of thermoplastic resin and thermosetting resin. Thermoplastic resins have functions such as adhesiveness, flexibility, relaxation of thermal stress, and improvement of insulation due to low water absorption, while thermosetting resins are heat resistant, insulating at high temperatures, This is important for achieving a balance between chemical properties and the strength of the adhesive layer.

  Examples of the thermosetting resin used in the present invention include known thermosetting resins such as epoxy resins, phenol resins, melamine resins, xylene resins, furan resins, and cyanate ester resins. Resins and phenolic resins are preferred.

  The epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule, but diglycidyl ether such as bisphenol A, bisphenol F, bisphenol S, resorcinol, dihydroxynaphthalene, dicyclopentadiene diphenol, Fats such as epoxidized phenol novolac (phenol novolac type epoxy resin), epoxidized cresol novolak (cresol novolac type epoxy resin), epoxidized trisphenylol methane, epoxidized tetraphenylol ethane, epoxidized metaxylenediamine and cyclohexane diepoxide And cyclic epoxy. Further, for imparting flame retardancy, a halogenated epoxy resin, particularly a brominated epoxy resin may be used.

  Examples of brominated epoxy resins include copolymerized epoxy resins of tetrabromobisphenol A and bisphenol A, or brominated phenol novolac type epoxy resins such as “BREN” -S (manufactured by Nippon Kayaku Co., Ltd.). . These brominated epoxy resins may be used in combination of two or more in consideration of bromine content and epoxy equivalent.

  As the phenol resin, any known phenol resin such as novolak type phenol resin and resol type phenol resin can be used. For example, alkyl substituted phenols such as phenol, cresol, pt-butylphenol, nonylphenol and p-phenylphenol, cyclic alkyl-modified phenols such as terpene and dicyclopentadiene, heterogeneous such as nitro group, halogen group, cyano group and amino group Examples thereof include those having a functional group containing an atom, those having a skeleton such as naphthalene and anthracene, and resins made of polyfunctional phenols such as bisphenol A, bisphenol F, bisphenol S, resorcinol and pyrogallol.

  The addition amount of the thermosetting resin is preferably 5 to 400 parts by weight, more preferably 100 to 200 parts by weight with respect to 100 parts by weight of the thermoplastic resin. When the addition amount of the thermosetting resin is less than 5 parts by weight, the adhesiveness after heat curing and the breaking strength of the adhesive layer are remarkably lowered, and the reflow heat resistance is lowered, which is not preferable. Moreover, when the addition amount of a thermosetting resin exceeds 400 weight part, since the relaxation effect of a thermal stress falls by the fall of coating property or the high elastic modulus of a hardening body, it is unpreferable.

  Examples of the thermoplastic resin used in the present invention include acrylonitrile-butadiene copolymer (NBR), acrylonitrile-butadiene rubber-styrene resin (ABS), polybutadiene, polyethylene, ethylene-butadiene-ethylene resin (SEBS), acrylic ester, Examples thereof include a copolymer (acrylic resin) having methacrylic acid ester as an essential copolymerization component, polyvinyl butyral, polyamide, polyester, polyimide, polyamideimide, and polyurethane. Moreover, these thermoplastic resins may have a functional group capable of reacting with the functional group of the above-mentioned thermosetting resin. Specific examples include functional groups such as amino group, carboxyl group, epoxy group, hydroxyl group, methylol group, isocyanate group, vinyl group and silanol group. These functional groups strengthen the bond with the thermosetting resin and improve the film strength and reflow heat resistance.

  Among these thermoplastic resins, butadiene is an essential co-polymer from the viewpoints of adhesiveness between the adhesive layer and the material forming the layer without the conductor pattern such as a heat sink, flexibility, and thermal stress relaxation effect. Copolymers to be combined are particularly preferable, and various types can be used. In particular, from the viewpoint of adhesion to metal and chemical resistance, thermoplastic resins such as acrylonitrile-butadiene copolymer (NBR), styrene-butadiene-ethylene resin (SEBS), and styrene-butadiene resin (SBS) are preferable. Used. Furthermore, from the viewpoint of adhesiveness and heat resistance, a copolymer having butadiene as an essential copolymer component and having a carboxyl group is preferable. For example, carboxyl group-containing NBR (NBR-C), carboxyl group-containing SEBS (SEBS-C ) And carboxyl group-containing SBS (SBS-C).

  Examples of NBR-C include those obtained by carboxylating terminal groups of a copolymer rubber obtained by copolymerizing acrylonitrile and butadiene at a molar ratio of about 10/90 to 50/50, or acrylonitrile, butadiene, acrylic acid and maleic acid. And a terpolymer rubber of a carboxyl group-containing copolymerizable monomer. As NBR-C, specifically, PNR-1H (manufactured by JSR Corporation), “Nipol” (registered trademark) 1072J, “Nipol” (registered trademark) DN612, “Nipol” (registered trademark) DN631 (Japan) Zeon Co., Ltd.), “Hiker” (registered trademark) CTBN (BF Goodrich Co., Ltd.) and the like. Moreover, MX-073 (Asahi Kasei Co., Ltd.) can be illustrated as SEBS-C, and D1300 (Shell Japan Co., Ltd.) can be illustrated as SBS-C.

  Moreover, as a thermoplastic resin, from the viewpoint of adhesiveness and thermal cycle resistance, a copolymer containing an acrylic acid ester and a methacrylic acid ester having a side chain having 1 to 8 carbon atoms as an essential copolymer component is also preferably used. Furthermore, from the viewpoint of adhesiveness and reflow heat resistance, a copolymer having an acrylic ester and a methacrylic ester as a copolymer component and having an epoxy group or a carboxyl group is more preferably used. Examples of such thermoplastic resins include epoxy group-containing acrylic rubber HTR-860 (manufactured by Teikoku Chemical Industry Co., Ltd.) and carboxyl group-containing acrylic rubber SG-280DR (manufactured by Teikoku Chemical Industry Co., Ltd.). .

  Adding an inorganic filler to the adhesive layer used in the present invention is not limited at all. Examples of the inorganic filler include crystalline silica powder, fused silica powder, alumina, aluminum hydroxide, silicon nitride, magnesium hydroxide, calcium aluminate hydrate, zirconium oxide, zinc oxide, antimony trioxide, antimony pentoxide, Examples thereof include titanium oxide, iron oxide, cobalt oxide, chromium oxide, talc, aluminum, gold, silver, nickel, iron, clay and mica. Among these, from the viewpoint of dispersibility, aluminum hydroxide, alumina and silica are preferable, and the average particle diameter (the particle diameter showing the maximum value in the particle size distribution measurement of the primary particles dispersed in the organic solvent) is 0.2 to 15 μm. Those are preferred. Further, from the viewpoint of reflow heat resistance, silica having a 5% weight loss temperature (thermal decomposition temperature) of 350 ° C. or higher by TGA (heating weight loss measurement), preferably spherical silica powder, more preferably fused spherical silica is preferably used. It is done.

  The blending amount of these inorganic fillers is preferably 10 to 50 parts by weight with respect to 100 parts by weight of the adhesive composition. The amount of the inorganic filler is more preferably 20 to 40 parts by weight. If the blending amount is less than 10 parts by weight, it is difficult to improve reflow heat resistance and film strength. Moreover, when a compounding quantity exceeds 50 weight part, the deterioration of coating property, the adhesive fall after hardening, etc. are seen.

  Moreover, you may add the hardening | curing agent and hardening accelerator of thermosetting resins, such as an epoxy resin, to the adhesive bond layer used by this invention. Examples of these additives include 3,3′5,5′-tetramethyl-4,4′-diaminodiphenylmethane, 3,3′5,5′-tetraethyl-4,4′-diaminodiphenylmethane, 3, 3'-dimethyl-5,5'-diethyl-4,4'-diaminodiphenylmethane, 3,3'-dichloro-4,4'-diaminodiphenylmethane, 2,2'3,3'-tetrachloro-4,4 '-Diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminobenzophenone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 3,4'-diaminodiphenylsulfone, 4 , 4′-diaminobenzophenone, 3,4,4′-triaminodiphenylsulfone and other aromatic polyamines, boron trifluoride triethyla Boron trifluoride amine complexes such as thiol complexes, 2-alkyl-4-methylimidazole, imidazole derivatives such as 2-phenyl-4-alkylimidazole, organic acids such as phthalic anhydride, trimellitic anhydride, dicyandiamide, and And triphenylphosphine. You may use these individually or in mixture of 2 or more types. The addition amount of these additives is preferably 1 to 30 parts by weight with respect to 100 parts by weight of the adhesive composition constituting the adhesive layer. When the addition amount is lower than 1 part by weight, the curing reaction does not proceed efficiently, and a decrease in adhesiveness after heat curing, a decrease in Tg, and a decrease in reflow heat resistance are observed. Moreover, when addition amount exceeds 30 weight part, the fall of the thermal stress relaxation effect of hardened | cured material and the lifetime of an adhesive bond layer will be seen.

  In addition to the above components, organic components and inorganic components such as antioxidants and ion scavengers can be added to the adhesive composition as long as the properties of the adhesive are not impaired. Examples of the organic component include crosslinked polymers such as styrene, NBR rubber, acrylic rubber, and polyamide. Examples of the antioxidant include hindered phenol-based and amine-based primary antioxidants, and sulfur-based and phosphorus-based secondary antioxidants. Examples of the ion scavenger include antimony trioxide and antimony pentoxide. These may be used alone or in combination of two or more. The average particle size of the fine particle component is preferably 0.02 to 15 μm, more preferably 0.2 to 5 μm. Moreover, 2-30 weight part of the whole adhesive composition is suitable for a compounding quantity.

  The thickness of the adhesive layer is preferably 10 μm to 250 μm, more preferably 10 μm to 150 μm, and still more preferably 20 μm to 100 μm.

  FIG. 2 is a schematic cross-sectional view showing one embodiment of the adhesive sheet for a semiconductor device of the present invention. The adhesive sheet for a semiconductor device in FIG. 2 is a laminate having a structure composed of at least one protective film 17 and one adhesive layer 18. Examples of the adhesive sheet for a semiconductor device of the present invention include a two-layer structure of protective film 17 / adhesive layer 18 or a three-layer structure of protective film 17 / adhesive layer 18 / protective film 17, as shown in FIG. The adhesive sheet for semiconductor devices corresponds to the latter.

  The adhesive sheet for a semiconductor device of the present invention is usually provided in a semi-cured state. The semi-cured state referred to here is a DSC (differential scanning) capable of measuring reactive functional groups in the adhesive. It indicates that the degree of cure by a calorimeter is 0 to 40%. The tensile elongation of the adhesive sheet for a semiconductor device of the present invention in a temperature range of 60 ° C. to 130 ° C. is particularly preferably 300% or more and 2000% or less. If the tensile elongation is less than 300%, the embedding property is poor, which may lead to the generation of bonded bubbles. On the other hand, if the tensile elongation exceeds 2000%, problems such as excessive adhesion of the adhesive and dripping may occur. The elongation can be adjusted by the primary structure and molecular weight of the raw material used and the degree of reaction of the thermosetting resin.

  The thickness of the laminate is not particularly limited, but is preferably 60 μm to 350 μm, more preferably 90 μm to 300 μm, and still more preferably 90 to 220 μm from the viewpoints of heat resistance and handleability.

  A semiconductor device component can be manufactured using the adhesive sheet for a semiconductor device. The component for a semiconductor device of the present invention is a material in an intermediate processing stage used for manufacturing a semiconductor device such as a substrate for a semiconductor integrated circuit. As the semiconductor device component, for example, a flexible printed circuit board or a TAB tape is used as a wiring board layer composed of an insulator layer and a conductor pattern, and a semi-cured adhesive having a protective film subjected to silicone treatment on one side or both sides thereof A wiring board with an adhesive in which an agent layer is laminated, and a metal plate (stiffener with an adhesive) such as copper, stainless steel or 42 alloy as a layer on which a conductor pattern is not formed. A so-called adhesive in which a semi-cured adhesive layer having a protective film is laminated on the outermost layer even when each of the insulating layer and the wiring board layer composed of the conductive pattern and the layer without the conductive pattern are formed. A substrate for a semiconductor integrated circuit is also included in the component for a semiconductor device of the present invention.

  The semiconductor device of the present invention refers to one manufactured using the adhesive sheet for a semiconductor device of the present invention. For example, the shape and structure are not particularly limited as long as it is a BGA type or LGA type package. The semiconductor integrated circuit substrate and IC can be connected by any of TAB gang bonding and single point bonding, wire bonding used for lead frames, resin sealing in flip chip mounting, and anisotropic conductive film connection. Good. A package called CSP is also included in the semiconductor device of the present invention.

  Next, although the example of the manufacturing method of the adhesive sheet for semiconductor devices of this invention, the board | substrate for semiconductor connection, and a semiconductor device is demonstrated, this invention is not limited to these manufacturing methods.

(1) Manufacture of adhesive sheet for semiconductor device (a) A paint prepared by dissolving the adhesive composition prepared for the present invention in a solvent is applied onto a light release protective film (CF1) having releasability. ,dry. It is preferable to apply so that the thickness of the adhesive layer is 10 to 100 μm. Drying conditions are 1 to 5 minutes at a temperature of 100 to 200 ° C. Solvents are not particularly limited, but aromatics such as toluene, xylene and chlorobenzene, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and aprotic polar solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone alone or a mixture are preferred. It is. The preferable amount of the solvent in the paint is 50 to 80 parts by weight, more preferably 70 to 80 parts by weight, assuming that the whole paint is 100 parts by weight. If the amount of the solvent is less than 50 parts by weight, the stirring efficiency of the paint is lowered and the life of the paint is shortened. On the other hand, if the amount of the solvent is more than 80 parts by weight, the coating property is deteriorated, which is not preferable.

  (B) The film of (a) above is laminated with a non-stretched polyolefin-based heavy release protective film layer having a release strength higher than that described above to obtain the adhesive sheet for a semiconductor device of the present invention. In order to further increase the adhesive thickness, the adhesive layer may be laminated a plurality of times.

(2) Manufacture of substrate for semiconductor connection (a) Creation of wiring substrate comprising insulator layer and conductor pattern 12 to 35 μm electrolytic copper foil is added to tape with adhesive for TAB at a temperature of 130 to 170 ° C. Lamination is performed under a condition of .about.0.5 MPa, and then a heat curing treatment is sequentially carried out in an air oven at a temperature of 80.degree. To 170.degree. C. to produce a TAB tape with copper foil. Photoresist film formation, etching, resist stripping, electrolytic nickel plating, electrolytic gold plating, and solder resist film creation are performed on the copper foil surface of the obtained TAB tape with copper foil by a conventional method to prepare a wiring board.

(B) Creation of a layer in which no conductor pattern is formed A metal plate such as a pure copper plate, nickel-plated copper plate, blackened copper plate or stainless steel plate having a thickness of 0.05 to 0.5 mm is degreased with acetone.

(C) Preparation of semiconductor connection board component (wiring board with adhesive) The wiring board layer composed of the insulator layer and the conductor pattern of (a) above has the adhesive sheet for a semiconductor device created in (1) above. Lamination after peeling off the light release protective film (CF1). The laminate surface may be a surface with or without a conductor pattern. The laminating temperature is 60 ° C. to 200 ° C., and the pressure is 0.1 to 5 MPa. Finally, depending on the shape of the semiconductor device, it is appropriately punched and cut.

(D) Creation of semiconductor connection board component (stiffener with adhesive) Light release protective film for adhesive sheet for semiconductor device prepared in (1) above on the layer where the conductor pattern of (b) is not formed Lamination is performed after removing (CF1). The laminating temperature is 60 ° C. to 200 ° C., and the pressure is 0.1 to 5 MPa. Finally, depending on the shape of the semiconductor device, it is appropriately punched and cut.

(E) Creation of a substrate for semiconductor connection (e-1) When using a wiring substrate with an adhesive Peel off the light release protective film (CF1) of the adhesive layer from the component (wiring substrate with an adhesive) in (c) above, Affix to a metal plate punched into a suitable shape. For example, the metal plate can be exemplified by a rectangular outer shape, in which a rectangular hole is punched in the center in accordance with the device hole of the wiring board. The bonding conditions are a temperature of 60 ° C. to 200 ° C. and a pressure of 0.1 to 5 MPa. Finally, post curing is performed at a temperature of 80 ° C. to 200 ° C. for about 15 to 180 minutes in order to heat and cure the adhesive in a hot air oven.

(E-2) When using a stiffener with an adhesive The part (d) with the adhesive (stiffener with an adhesive) is punched out with a mold, for example, an adhesive having a square outer shape and a square hole at the center. Use a stiffener with an agent. The heavy peeling protective film (CF2) is peeled off from the stiffener with adhesive, and the central hole of the stiffener with adhesive is formed in the conductor pattern surface or the back polyimide film surface of the wiring substrate layer of (a) above. Match the holes and paste them together. The bonding conditions are a temperature of 60 ° C. to 200 ° C. and a pressure of 0.1 to 5 MPa. Finally, post curing is performed at a temperature of 80 ° C. to 200 ° C. for about 15 to 180 minutes in order to heat and cure the adhesive in a hot air oven.

  FIG. 3 is a schematic cross-sectional view showing one embodiment of a semiconductor connection substrate which is one of the components for a semiconductor device of the present invention obtained as described above. In FIG. 3, an insulating layer 11 for connecting the semiconductor integrated circuit 1, a conductor 13 for connecting the semiconductor integrated circuit, and a wiring board layer comprising an adhesive layer 12, a reinforcing plate (stiffener), a heat sink (heat spreader). The layer 15 is not formed with a conductor pattern such as a shield plate, and has at least one layer of an adhesive layer 14 and a solder resist 16 for laminating them.

(3) Manufacture of Semiconductor Device The inner lead portion of the semiconductor connection substrate of (2) above is thermocompression-bonded (inner lead bonding) to an IC gold bump, and the IC is mounted. Next, a semiconductor device is manufactured through resin sealing. The obtained semiconductor device is connected to a printed circuit board or the like on which other components are mounted via solder balls, and mounted on an electronic component.

  EXAMPLES Examples will be given below to describe the adhesive sheet for semiconductor devices of the present invention in detail, but the present invention is not limited to these examples. First, the evaluation method will be described.

[Evaluation methods]
(1) Bonded surface void observation:
A three-layer TAB tape in which an adhesive layer and a protective film layer are laminated on a polyimide film is processed by the following steps (a) to (d). (A) Drilling process of sprocket and device hole, (b) Thermal laminating process with copper foil, and (c) Tin or gold plating process. (D) An adhesive layer having a thickness of 100 μm is formed at a temperature of 130 ° C. on the conductor pattern surface of a 30 mm square wiring board layer on which a simulated pattern having a conductor width of 100 μm and a conductor distance of 100 μm obtained as described above is formed. Pasting was performed by a press method under the condition of a pressure of 0.5 MPa for 5 min. Using the ultrasonic flaw detector (MISSCOPE, manufactured by Hitachi Construction Machinery Finetech Co., Ltd.), confirm the presence or absence of voids on the bonding surface (visual confirmation from the image taken by the ultrasonic flaw detector). )did. In addition, after confirming that the void in the adhesive bond layer before bonding with a wiring board layer did not generate | occur | produce, this evaluation is performed.

(2) Protective film peel strength:
In the case of a light release protective film, an adhesive sheet having a width of 30 mm is attached to a stainless steel plate with a double-sided tape, and peeled at a rate of 300 mm / min in the 90 ° direction. The adhesive layer and the light release protective film (CF1) at that time The peel force was measured. On the other hand, in the case of the heavy release protective film (CF2), the light release protective film is peeled off from the adhesive sheet having a width of 30 mm, and the adhesive layer is attached to the stainless steel plate with a double-sided tape, and peeled at a rate of 300 mm / min in the 90 ° direction. Then, the peel strength of the heavy release protective film (CF2) and the adhesive layer at that time was measured.

(3) Heavy peel protective film peel force (after pressing):
A TAB tape having a three-layer structure in which an adhesive layer and a protective film layer are laminated on a polyimide film is processed by the following steps (a) to (d). (A) Drilling process of sprocket and device hole, (b) Thermal laminating process with copper foil, and (c) Tin or gold plating process. (D) An adhesive layer having a thickness of 100 μm was laminated on the conductive pattern surface of the wiring board layer obtained as described above at a temperature of 130 ° C. and a pressure of 0.5 MPa for 5 minutes. The wiring board layer side was bonded to a stainless steel plate with a double-sided tape, and the heavy release protective film was peeled off at a rate of 300 mm / min in the 90 ° direction. At that time, the peel force between the heavy peel protective film (CF2) and the adhesive layer was measured. .

(4) Reflow resistance:
A 100 μm thick adhesive layer is applied at a temperature of 130 ° C. and a pressure of 0.5 MPa on the surface on which the conductor pattern of the 30 mm square semiconductor connection substrate on which a simulated pattern having a conductor width of 100 μm and a conductor distance of 100 μm is formed. After press bonding under conditions of 5 min, 30 mm square 0.25 mm thick SUS304 was laminated at a temperature of 130 ° C. under a pressure of 0.5 MPa for 5 min. Then, it hardened | cured on the conditions of 2Hr at the temperature of 150 degreeC, and produced the sample for reflow-proof evaluation. A 30 mm square sample was absorbed at 168 Hr at 30 ° C. under 70% RH, and then immediately subjected to IR reflow at a maximum temperature of 220 to 280 ° C. for 10 seconds, and the peeled state was determined by an ultrasonic flaw detector (MISSCOPE, Hitachi Observation was carried out using Construction Machinery Finetech Co., Ltd. In this test, the maximum temperature at which peeling was not observed was defined as the reflow heat resistance temperature. A reflow heat-resistant temperature lower than 260 ° C. is not preferable because it does not correspond to lead-free.

(5) Thermal cycle resistance:
Twenty 30 mm square evaluation samples prepared by the method of (4) above were prepared for each level, and the temperature was -65 ° C to 150 ° C in a heat cycle tester (PL-3 type, manufactured by Tabay Espec Co., Ltd.). Processing was performed under the conditions of holding at the minimum and maximum temperatures for 30 minutes each, and the occurrence of peeling was evaluated. Samples were taken out at the end of each of 100 cycles, 300 cycles, 500 cycles and 800 cycles, and the occurrence of peeling was evaluated. If one of the 20 pieces was peeled off, it was judged as defective.

(6) Measurement of tensile elongation of protective film and adhesive sheet:
A sample having a thickness of 25 μm (protective film) and a thickness of 50 μm (adhesive sheet) is 40 mm long. A tensile test is performed at a speed of 50 mm / min using a tensile tester (UCT100 type, manufactured by Orientec Co., Ltd.) to break the sample. A stress-strain curve was recorded to determine the tensile elongation.

Examples 1-8, Comparative Examples 1-10
(Creation of adhesive sheet)
The following thermoplastic resin, epoxy resin, and other additives are blended so as to have the composition ratios shown in Table 1, respectively, and dimethylformaldehyde (DMF) / monochlorobenzene is added so that the solid content concentration is 28 parts by weight. It was blended in a (CB) / methyl isobutyl ketone (MIBK) mixed solvent and stirred and dissolved at a temperature of 40 ° C. to prepare an adhesive solution.

A. Epoxy resin Bisphenol A type epoxy resin (epoxy equivalent: 186) (manufactured by Japan Epoxy Resin Co., Ltd., “Epicoat” (registered trademark) 828)
B. Thermoplastic resin Carboxyl-modified acrylic rubber (Teikoku Chemical Industry Co., Ltd., SG-280DR)
C. Inorganic filler Spherical silica powder (manufactured by Admatechs, SO-C2)
D. Curing agent 4,4′-DDS: 4,4′-diaminodiphenyl sulfone (Sumitomo Chemical Co., Ltd., “SumiCure” (registered trademark) S)
E. Protective film The following silicone resin and the following amount of cross-linking agent are dissolved in toluene so that the silicone resin concentration is 0.1 wt%, and this solution is applied to the following film in a predetermined amount, and is placed in an oven at a temperature of 100 ° C for 5 minutes. Drying was performed, and simultaneously with drying of the solvent, the silicone resin was crosslinked to form a three-dimensional crosslinked silicone resin coating film.

Silicone resin (SPX520 manufactured by Toray Dow Corning Silicone Co., Ltd.)
Cross-linking agent (SPX212CAT manufactured by Toray Dow Corning Silicone Co., Ltd.)
Silicone resin coating amount: 0.03 g / m ² (light release protective film), 0.015 g / m ² .

(Heavy peel protection film)
1. Polyimide film (PI) Ube Industries, Ltd., “UPILEX” (registered trademark) 25S)
2. Polyethylene terephthalate film (PET) (Toyobo Co., Ltd., Toyobo Ester E5100)
3. Unstretched polyethylene terephthalate film (Toray Metallizing Co., Ltd. “Therapel” (registered trademark) WZ (APT))
4). Nylon (NY) (manufactured by Toyobo Co., Ltd., Harden (registered trademark) N1100)
5. Non-stretched nylon (manufactured by Toray Synthetic Film Co., Ltd., Reyfan (registered trademark) NO1401)
6). Polyethylene (low density) (PE) (Toyobo Co., Ltd., LIX-2)
7). Polyethylene (high density) (Tosero Co., Ltd., O-PE)
8. Non-stretched polyethylene (low density) (TUXO, TUXHZ)
9. Polypropylene (PP) (Toyobo Co., Ltd., Pyrene (registered trademark) P2161)
10. Unstretched polypropylene (Toyobo Co., Ltd., Pyrene (registered trademark) P1010)
11. Polyphenylene sulfide (PPS) (Toray Industries, Inc. Torelina (registered trademark))
The obtained adhesive solution was applied with a bar coater to a 38 μm-thick lightly peeled protective film (CF1) that had been subjected to a silicoat treatment so as to have a dry thickness of about 50 μm. The adhesive sheet was produced by drying at a temperature of 5 minutes. On the other hand, a semiconductor device having a 25 μm thick heavy peel protective film (CF 2) having a higher peel strength than the light peel protective film (CF 1) is bonded to the adhesive side at a temperature of 80 ° C., and has a protective film on both sides of a 50 μm thickness An adhesive sheet was prepared. The adhesive sheet for semiconductor device was measured for the presence or absence of voids on the bonded surfaces, tensile elongation, reflow heat resistance and thermal cycle resistance. The results are summarized in Tables 1 and 2.

  From the above examples, the adhesive sheet for a semiconductor device according to the present invention achieves easy processability by defining the tensile elongation in the temperature range of 60 ° C. to 130 ° C. of the heavy release protective film, and the reflow heat resistance and The thermal cycle resistance was excellent. On the other hand, the above comparative examples were inferior in easy processability and reflow heat resistance.

  The adhesive sheet for a semiconductor device of the present invention is a substrate for semiconductor connection used in a ball grid array (BGA), a chip scale package (CSP) having a BGA structure, a land grid array (LGA), and a pin grid array (PGA) system. It is possible to use for bonding between a wiring board layer composed of an insulating layer and a conductor pattern that constitutes a layer and a layer on which a conductor pattern such as a metal plate (stiffener or heat spreader) is not formed. Moreover, the obtained adhesive sheet for a semiconductor device can be suitably used for a semiconductor device component and a semiconductor device.

DESCRIPTION OF SYMBOLS 1 Semiconductor integrated circuit 2 Gold bump 3, 11 Insulator layer 4, 12 Adhesive layer which comprises wiring board layer 5, 13 Conductor for connecting semiconductor integrated circuit 6, 14, 18 Adhesive layer 7, 15 Conductor pattern is formed Layers 8 and 16 Solder resist 9 Solder balls 10 Sealing resin 17 Protective film

Furthermore, since the heavy release protective film (CF2) is peeled off after the adhesive layer (A) is attached to the adherend by laminating or pressing at a temperature of 60 ° C. to 130 ° C., the peel strength after heating it is important, peel force after 5 minutes heating at a temperature of 130 ℃ (F2 ') is 3N / m or more and less 70N / m. If it is less than 3 N / m, the heavy release protective film may fall off, and if it is more than 70 N / m, peeling may be difficult.

Claims (3)

A light release protective film, an adhesive layer and a heavy release protective film are laminated in this order, and are an adhesive sheet for a semiconductor device, wherein there is a difference in peel force between the light release protective film and the heavy release protective film with respect to the adhesive layer. 5N / m or more, the elongation at 100 ° C. of the heavy release protective film is 500% or more and 1,800% or less, and the elongation of the adhesive layer at 100 ° C. is 300% or more and 2000% or less. And an adhesive sheet for a semiconductor device, wherein the heavy peel protective film has a peel force of 3 N / m to 70 N / m after heating for 5 minutes at a temperature of 130 ° C. . The adhesive sheet for a semiconductor device according to claim 1, wherein the heavy release protective film has a melting point of 130 ° C. or higher. Heavy release protective film is unstretched polyester, unstretched polypropylene, high density polyethylene, unstretched polyamide, unstretched polyphenylene sulfide, unstretched polyvinyl chloride, unstretched polytetrafluoroethylene, unstretched polyvinyl fluoride, unstretched polyvinyl butyrate. 2. The adhesive sheet for a semiconductor device according to claim 1, wherein the adhesive sheet is made of a latex, unstretched polyvinyl acetate or unstretched polyvinyl alcohol.

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