JP5343335B2 - Adhesive sheet for electronic equipment - Google Patents

Description

  The present invention relates to an adhesive sheet for electronic equipment. More specifically, tape automated bonding (TAB) pattern processing tape, semiconductor grid connection substrates such as ball grid array (BGA) package interposers, lead frame fixing tape, which are used when mounting semiconductor integrated circuits, Lead-on-chip (LOC) fixing tapes, die bonding materials used for bonding electronic components such as semiconductor elements and support members such as lead frames and insulating support substrates, heat sinks (heat spreaders), reinforcing plates (stiffeners), Adhesive sheets for electronic devices suitable for producing various electronic materials such as adhesives for shield materials, solder resists, anisotropic conductive films, copper-clad laminates, coverlays, metal substrates, and insulating layers between circuits Electronic component using the same, and method for manufacturing a substrate with a metal layer using the electronic component To.

  In recent years, along with improvements in mounting technology for electronic devices, the size and thickness of devices have been reduced, and as a result, the usage of electronic devices has been increasing. When downsizing and thinning electronic equipment, the density of heat generated from the equipment increases, so the generation of heat is suppressed, and the use of electronic components such as semiconductor integrated circuit (IC) packages, transistors, diodes, and power supplies It is important to efficiently release the generated heat to the outside. Further, as the operating frequency of a microchip processor (MPU) used in a personal computer or the like increases, the amount of heat generated from the MPU chip has become very large. Further, since flat panel displays (FPD) represented by plasma panel displays and liquid crystal displays generate heat in the display panel, it is important to release this heat to the outside.

  Generally, in order to release the heat generated from the electronic components as described above, it is known to attach a heat radiating component having a larger heat radiating area such as a heat sink, a metal plate, or an electronic device casing to the electronic component serving as a heat source. It has been. At this time, the interface between the electronic component and the heat radiating component is a resistance in terms of heat transfer. For this reason, as means for assisting heat transfer at the interface, a thermally conductive silicone grease containing aluminum nitride and zinc oxide powder (see, for example, Patent Document 1), and a heat dissipation spacer made of a solidified silicone containing a thermally conductive filler (eg, Patent Document 2) has been proposed. However, these heat radiating materials themselves have no adhesiveness, and thus it is necessary to fix the members separately.

  From the viewpoint of workability, there is a demand for a material that can fix an electronic component and a heat dissipation component in addition to heat transfer at the interface. As a material that can meet such a requirement, an adhesive sheet obtained by processing an adhesive composition containing a thermosetting resin and a filler having high thermal conductivity into a sheet shape can be given. For example, a thermal conductive adhesive composition having a thermal conductivity of 0.6 W / m · K or more, including an epoxy resin and its curing agent, a high molecular weight resin, a curing accelerator, and spherical alumina is applied on a substrate. There has been proposed a heat conductive adhesive film in which the heat generation of 10 to 40% of the total heat generation when the degree of cure is measured using DSC is finished (see, for example, Patent Document 3). However, the heat conductivity of this heat conductive adhesive film is not sufficient, and the adhesiveness is not sufficient.

As a method for improving the thermal conductivity of the heat dissipation material, increasing the filling rate of the thermal conductive filler can be mentioned. For example, an adhesive composition containing a resin and a filler, wherein the filler satisfies at least (A) 0.5 μm ≦ R ≦ 5 μm and K ≦ 15, where R is the average particle size and K is the flatness ratio. Filler is X% of the total amount of filler, (B) Y% of the total amount of filler satisfying 5 μm ≦ R ≦ 30 μm and K ≦ 15, and (C) Filler satisfying 1 μm ≦ R ≦ 10 μm and 20 ≦ K ≦ 60 Including X% of the total amount, and X, Y, and Z satisfy 0.25 ≦ X / Z ≦ 3.5 and 0.6 ≦ (X + Z) / Y ≦ 5, and (A), (B) and There has been proposed an adhesive composition in which the total amount of each filler satisfying (C) is 30 vol% or more and 60 vol% or less with respect to the total volume of the adhesive composition (see, for example, Patent Document 4). However, the adhesive strength of the heat conductive adhesive film is not sufficient, and the heat dissipation is not sufficient.
Japanese Patent No. 3142800 (Claim 1) Japanese Patent No. 3092699 (Claims 1-2, 5) Japanese Patent No. 3559137 (Claim 1) JP 2004-168870 A (Claim 1, paragraphs 0031 to 0032)

  As described above, the conventional heat conductive adhesive sheet has insufficient adhesiveness. An object of this invention is to provide the adhesive sheet for electronic devices excellent in heat conductivity and adhesiveness in view of the subject of this prior art.

In order to solve the above problems, the present invention mainly has the following configuration. That is, an adhesive sheet for electronic equipment having at least an adhesive layer and a protective film layer that can be peeled off, wherein the adhesive layer comprises (A) an epoxy resin, (B) a curing agent, (C) a thermoplastic resin, and ( D) a thermally conductive filler, (D) an inorganic powder having an average particle diameter of 1 to 10 μm selected from the group consisting of (d1) aluminum nitride, silicon nitride and boron nitride, and (d2) consists spherical alumina powder having an average particle diameter of 0.01 to 1 [mu] m, the content ratio of d1: d2 is in weight ratio of 95: 5 to 50: 50 der Ri, (D) an adhesive layer in the thermally conductive filler An adhesive sheet for electronic equipment , containing 35.5-77.8% by volume, wherein (D) a thermally conductive filler is surface-treated with a silane coupling agent .

  The adhesive sheet for electronic equipment of the present invention is excellent in thermal conductivity and excellent in adhesion to an adherend. For this reason, it can use suitably in order to adhere heat generating parts in electronic equipment, and heat dissipation parts, such as a heat sink and a heat sink. Furthermore, an electronic device having excellent heat dissipation characteristics can be obtained by bonding the heat-generating component and the heat-dissipating component using the adhesive sheet for electronic device of the present invention or by laminating a printed circuit board.

  The adhesive sheet for electronic devices (hereinafter referred to as adhesive sheet) of the present invention is a sheet for bonding heat generating components in electronic devices to heat radiating components such as heat sinks and heat sinks, stiffeners, heat spreaders, semiconductor elements and wiring boards. TAB pattern processing tape used when mounting semiconductor integrated circuits for (interposers), semiconductor connection substrates such as BGA package interposers, FPC and its reinforcing plates, coverlays, copper-clad laminates, multilayers Interlayer adhesive for substrates, and substrate components, lead frame fixing tapes, LOC fixing tapes, adhesives between electronic components such as semiconductor elements and supporting members such as lead frames and insulating support substrates, that is, die bonding materials, It can be used for a shield material or the like, and the shape and material of these adherends are not particularly limited.

Hereinafter, the configuration of the present invention will be described in detail. The adhesive sheet of the present invention has at least an adhesive layer and a protective film layer that can be peeled off. The adhesive layer contains (A) an epoxy resin, (B) a curing agent, (C) a thermoplastic resin, and (D) a thermally conductive filler, and (D) the thermally conductive filler is (d1). An inorganic powder having an average particle diameter of 1 to 10 μm selected from the group consisting of aluminum nitride, silicon nitride and boron nitride, and (d2) a spherical alumina powder having an average particle diameter of 0.01 to 1 μm, and the content ratio d1: d2 is 95 in a weight ratio: 5 to 50: 50 der Ri, (D) an adhesive layer in the thermally conductive filler contained from 35.5 to 77.8 vol%, (D) a thermally conductive filler is a silane coupling It is characterized by being surface-treated with a ring agent .

  The adhesive sheet of the present invention contains (A) an epoxy resin in the adhesive layer. By including an epoxy resin, it is possible to achieve a balance of physical properties such as heat resistance, insulation at high temperatures, chemical resistance, and strength when formed into an adhesive layer. The epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. For example, a cresol novolac type epoxy resin, a phenol novolac type epoxy resin, an epoxy resin containing a biphenyl type skeleton, a naphthalene skeleton -Containing epoxy resins, bisphenol-type epoxy resins, dicyclopentadiene-type epoxy resins, linear aliphatic epoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, spiro-ring-containing epoxy resins, and halogenated epoxy resins . Two or more of these may be contained.

  Among these epoxy resins, bisphenol F-type epoxy resins and bisphenol A-type epoxy resins are preferably used in the present invention because they are excellent in adhesiveness and film forming properties when forming an adhesive composition into a sheet. Among them, a bisphenol A type epoxy resin having a low molecular weight and a single viscosity of 25 Pa · s or less is particularly preferable. By using such a resin, the followability of the adhesive layer to the adherend surface is improved, and the adhesiveness is further improved. The viscosity of the epoxy resin is measured with a B-type viscometer at 25 ° C.

  The adhesive sheet of this invention contains the (B) hardening | curing agent which carries out a crosslinking reaction with an epoxy group in an adhesive bond layer. The adhesive force after hardening improves by containing the hardening | curing agent which carries out a crosslinking reaction with an epoxy group. Examples of curing agents 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'-diaminodiphenyl methane, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminobenzophenone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, Aromatic polyamines such as 4,4′-diaminobenzophenone and 3,4,4′-triaminodiphenylsulfone, boron trifluoride tri Amine complexes of boron trifluoride such as ethylamine complex, dicyandiamide, phenol novolak, novolak resins such as cresol novolak, bisphenol compounds such as bisphenol A can be used. Of these, phenolic curing agents are preferred because of their excellent heat resistance. These may be used alone or in combination of two or more.

  The adhesive sheet of the present invention has a ratio H / E of (B) the total number of moles of active hydrogen H in the curing agent and (A) the total number of moles E of epoxy groups in the epoxy resin contained in the adhesive layer. Is preferably in the range of 0.4 to 1.2 from the viewpoint of improving adhesiveness. Usually, the ratio H / E of the total mole number H of active hydrogen in the curing agent and the total mole number E of epoxy groups in the epoxy resin is preferably in the range of 0.8 to 1.2, centering on 1.0. Although it is often designed, adhesion to an adherend and solder heat resistance are improved by making the epoxy group excessive and setting H / E to 0.4 to 1.2. More preferably, it is 0.4-0.7.

  The adhesive sheet of the present invention contains (C) a thermoplastic resin in the adhesive layer. By containing a thermoplastic resin, toughness can be imparted, and effects such as improved adhesion, improved flexibility, and relaxation of thermal stress can be obtained.

  Thermoplastic resins include acrylonitrile-butadiene copolymer (NBR), acrylonitrile-butadiene rubber-styrene resin (ABS), polybutadiene, styrene-butadiene-ethylene resin (SEBS), and acrylic having 1 to 8 carbon side chains. Examples include acid and / or methacrylic acid ester resin (acrylic rubber), polyvinyl butyral, polyamide, polyester, polyimide, polyamideimide, polyurethane and the like.

  These thermoplastic resins preferably have a functional group capable of reacting with the above-described (A) epoxy resin. Specific examples include amino groups, carboxyl groups, epoxy groups, hydroxyl groups, methylol groups, and isocyanate groups. These functional groups are preferable because the bond with the epoxy resin becomes strong and the heat resistance is improved.

  Among these thermoplastic resins, copolymers having acrylic acid and / or methacrylic acid esters having a side chain having 1 to 8 carbon atoms as essential copolymerization components from the viewpoints of adhesiveness, flexibility and thermal stress relaxation effect. A polymer can be particularly preferably used. Moreover, these copolymers may also have a functional group capable of reacting with the above-described epoxy resin. In this case, it is more preferable to use a copolymer having a carboxyl group and / or a hydroxyl group as a functional group in combination with a copolymer having another functional group. The functional group content is preferably 0.07 to 0.7 eq / kg, more preferably 0.07 to 0.45 eq / kg, and still more preferably 0.07 to 0.14 eq / kg.

  In the present invention, the content of the thermoplastic resin (C) is preferably 2% by weight or more, more preferably 5% by weight or more, and preferably 30% by weight or less in the adhesive layer in the adhesive sheet. Preferably it is 20 weight% or less.

The adhesive sheet of the present invention contains (D) a thermally conductive filler in the adhesive layer. The term “thermally conductive filler” as used herein refers to a filler having a thermal conductivity of 10 (Wm ⁻¹ K ⁻¹ ) or more as a single filler. The thermal conductivity can be measured by a laser flash method. For example, the thermal diffusivity is measured using a thermal constant measuring device TC-7000 manufactured by ULVAC-RIKO, and the thermal conductivity is calculated from the separately measured density and specific heat parameters.

  In the present invention, the thermally conductive filler is composed of inorganic powder (d1) having an average particle diameter of 1 to 10 μm selected from the group consisting of aluminum nitride, silicon nitride and boron nitride, and spherical particles having an average particle diameter of 0.01 to 1 μm. It consists only of alumina powder (d2). Moreover, the content ratio of d1 and d2 is 95: 5 to 50:50 by weight ratio.

  By containing the inorganic powder (d1) having an average particle diameter of 1 to 10 μm selected from aluminum nitride, silicon nitride, and boron nitride, the thermal conductivity of the adhesive is greatly improved. Preferably it is 1-5 micrometers. The particle shape and crystallinity are not particularly limited, and a crushing system, a spherical shape, a scale shape, and the like are used. From the viewpoint of dispersibility in the paint, a spherical shape is preferably used. Moreover, the adhesiveness of an adhesive agent sheet improves greatly by containing spherical alumina powder (d2) with an average particle diameter of 0.01-1 micrometer. This is because the average particle size of the inorganic powder (d1) is 1 μm to 10 μm, and the average particle size of the spherical alumina powder (d2) is 0.01 to 1 μm, so that the spherical alumina is formed in the gap between the inorganic powders (d1). It is considered that the powder (d2) is filled and the filling rate of the heat conductive filler in the adhesive sheet is improved.

  In the present invention, the average particle diameter means a particle diameter (median diameter) corresponding to 50% when the particle size distribution is measured with a particle size distribution meter and the cumulative distribution is expressed in percent (%). When the particles are not spherical, the particle size distribution based on the sphere equivalent volume is measured. Examples of the particle size distribution meter include Horiba LA500 laser diffraction particle size distribution meter. In addition, a particle size distribution shall display a particle diameter display on a volume basis, and a 56 division piece logarithm display (0.1-200 micrometers).

  The content ratio of d1 and d2 is (d1) :( d2) = 95: 5 to 50:50 in weight ratio. When the weight ratio is within this range, the adhesiveness is improved and the thermal conductivity is sufficient. Preferably it is 95: 5-70: 30.

  The content of the heat conductive filler (D) in the adhesive layer is preferably 40% by volume or more from the viewpoint of heat conductivity. Moreover, from an adhesive viewpoint, 75 volume% or less is preferable and 60 volume% or less is more preferable. If it is this range, heat conductivity and adhesive force can be made compatible at a higher level.

  (D) The thermally conductive filler is used for the purpose of preventing alteration such as oxidation and hydrolysis of the filler, the purpose of improving the wettability between the filler and other organic components in the adhesive composition, and the adhesive sheet. A surface treatment may be applied to improve physical properties. Specific examples include coating with silica, phosphoric acid, etc., oxide film application treatment, silane coupling agent, titanate coupling agent, surface treatment with silane compound, etc. Also good.

In the present invention, surface-treated with a silane coupling agent (D) a thermally conductive filler. By performing such a surface treatment, (D) the thermally conductive filler is more uniformly dispersed in the adhesive composition, and as a result, the solder heat resistance and adhesiveness can be improved. Specific examples of the silane coupling agent include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and vinyltrimethoxy. Silane, vinyltriethoxysilane, 2- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3 -Methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltri Toxisilane, N-2 (aminoethyl) 3-aminopropylmethyldimethoxysilane, N-2 (aminoethyl) 3-aminopropyltrimethoxysilane, N-2 (aminoethyl) 3-aminopropyltriethoxysilane, 3-tri Ethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, 3-ureidopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, etc. Among them, 3-glycidoxypropyltrimethoxysilane and N-phenyl-3-aminopropyltrimethoxysilane are particularly preferable in terms of improving the wettability between the filler and other organic components in the resin composition. . The silane coupling agent may be used alone or two or more of the above silane coupling agents may be used, and the amount used for the treatment is 0.3 to 100 parts by weight of the thermally conductive filler. 1 part by weight is preferred. Further, the adhesive composition may contain a filler other than (D) the heat conductive filler, and when these fillers are combined and subjected to a surface treatment, the adhesive composition is added in an amount of 0.1% relative to a total of 100 parts by weight of the filler. About 3 to 1 part by weight is preferred.

  In the adhesive sheet of the present invention, the content of (A) the epoxy resin is (D) 100 parts by weight of the thermally conductive filler, and the adhesive composition contains (D) a filler other than the thermally conductive filler. Is preferably 8.2 to 19.0 parts by weight with respect to 100 parts by weight of the total.

  The adhesive sheet of the present invention may contain a curing catalyst as necessary. Curing accelerators include boron trifluoride amine complexes such as boron trifluoride triethylamine complex, 2-alkyl-4-methylimidazole, dicyandiamide, triphenylphosphine, tetra-n-butylphosphonium o, o-diethyl. Known compounds such as phosphorodithioate and sulfonium salt derivatives can be used. These may be used alone or in combination of two or more. Among these, it is preferable to contain a phosphine-based curing catalyst in terms of curability and reliability. By containing a phosphine-based curing catalyst, curability and storage stability at room temperature are improved. Specific examples of the phosphine-based curing catalyst include triphenylphosphine, trimethylphosphine, triethylphosphine, tri-n-butylphosphine, tri-n-octylphosphine, tricyclohexylphosphine, tribenzylphosphine, tri-o-tolylphosphine, Tri-m-tolylphosphine, tri-p-tolylphosphine, tris- (p-methoxyphenyl) phosphine, diphenylcyclohexylphosphine, tetraphenylphosphonium tetraphenylborate, triphenylphosphinetriphenylborane, tri (nonylphenyl) phosphine Triphenylphosphine is particularly preferably used from the viewpoint of curing acceleration.

  It is preferable that content of a curing catalyst exists in the range of 0.3-3.0 weight part with respect to 100 weight part of (A) epoxy resins. By setting it to 0.3 parts by weight or more, a curing promoting effect is obtained, and by setting it to 3.0 parts by weight or less, storage stability is improved.

  The adhesive sheet of this invention says the thing of the structure which has the adhesive bond layer which consists of an adhesive composition, and the peelable protective film layer. For example, a two-layer structure of a protective film layer / adhesive layer or a three-layer structure of a protective film layer / adhesive layer / protective film layer corresponds to this. Moreover, you may have another layer other than an adhesive bond layer and a protective film layer. For example, a composite structure in which a heat conductive material such as a carbon fiber cloth is laminated inside the adhesive layer, or a composite structure in which an insulating film such as polyimide is laminated inside the adhesive layer.

  Although the thickness of an adhesive bond layer can be suitably selected in relation to an elastic modulus and a linear expansion coefficient, it is preferably 10 to 500 μm, more preferably 20 to 200 μm. As long as the adhesive layer can follow the unevenness on the surface of the adhesive member, it is preferable that the adhesive layer is as thin as possible in terms of heat conduction.

  Before the adhesive layer is bonded to the wiring substrate layer (TAB tape or the like) composed of the insulator layer and the conductor pattern or the layer (stiffener or the like) where the conductor pattern is not formed, the protective film layer If it can peel without impairing a function, it will not specifically limit. For example, plastic films such as polyester, polyolefin, polyphenylene sulfide, polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, polyvinyl butyral, polyvinyl acetate, polyvinyl alcohol, polycarbonate, polyamide, polyimide, polymethyl methacrylate, Examples thereof include films obtained by coating a release agent such as silicone or a fluorine compound, papers laminated with these films, and papers impregnated or coated with a releasable resin. The protective film layer may be colored with a pigment so as to have good visibility during processing. Thereby, since the protective film of the side which peels previously can be recognized easily, misuse can be avoided.

When the protective film layers are provided on both surfaces of the adhesive layer, when the peeling force of each protective film layer to the adhesive layer is F ₁ and F ₂ (F ₁ > F ₂ ), F ₁ -F ₂ is preferably It is 5 Nm ⁻¹ or more, more preferably 15 Nm ⁻¹ or more. By setting F ₁ -F ₂ to 5 Nm ⁻¹ or more, the target protective film layer can be stably peeled off, so that workability is good. Further, the peeling forces F ₁ and F ₂ are preferably ¹ to 200 Nm ⁻¹ , more preferably 3 to 100 Nm ⁻¹ . If it is this range, troubles, such as omission of a protective film layer and damage to an adhesive bond layer, can be prevented.

  Next, the example of the manufacturing method of the adhesive sheet of this invention is demonstrated.

  (A) A paint obtained by dissolving the adhesive composition in a solvent is applied on a polyester film having releasability and dried. The thickness of the adhesive layer is preferably 10 to 500 μm. The drying conditions are preferably 100 to 200 ° C. and 1 to 5 minutes. When the film thickness of the adhesive layer exceeds 100 μm, it may be applied in a plurality of times. Further, two or more adhesive layers having a thickness of 100 μm or less may be prepared and laminated by lamination. Solvents are not particularly limited, but aromatic solvents such as toluene, xylene and chlorobenzene, ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, aprotic polar solvents such as dimethylformamide, dimethylacetamide and N methylpyrrolidone, or a mixture thereof. Is preferred.

  (B) The adhesive sheet of the present invention is obtained by laminating a polyester or polyolefin-based protective film layer having a releasability with a lower peel strength than the above to the film of (a). In order to further increase the adhesive thickness, the adhesive layer may be laminated a plurality of times. After lamination, for example, the degree of curing may be adjusted by heat treatment at 40 to 70 ° C. for about 20 to 200 hours.

  The electronic component in the present invention refers to one produced using the adhesive sheet of the present invention, and examples thereof include a substrate for connecting a semiconductor integrated circuit and a substrate with a metal layer.

  The substrate for connecting a semiconductor integrated circuit is for connecting an isolated semiconductor integrated circuit (bare chip) after an element is formed on a semiconductor substrate such as silicon. (A) A wiring composed of an insulator layer and a conductor pattern The shape, material, and manufacturing method are not particularly limited as long as each of the substrate layer, (B) the layer on which the conductor pattern is not formed, and (C) one or more adhesive layers. Therefore, the most basic one is an A / C / B configuration, but a multilayer structure such as A / C / B / C / B is also included.

  (A) A wiring board layer composed of an insulator layer and a conductor pattern is a layer having a conductor pattern for connecting an electrode pad of a semiconductor element and the outside of a package (printed board, etc.), and one or both sides of the insulator layer A conductor pattern is formed on the substrate.

  The insulator layer here is made of a composite material such as polyimide, polyester, polyphenylene sulfide, polyethersulfone, polyetheretherketone, aramid, polycarbonate, polyarylate, or a plastic or epoxy resin-impregnated glass cloth. A 125 μm flexible insulating film or a ceramic substrate such as alumina, zirconia, soda glass, or quartz glass is suitable, and a plurality of layers selected from these may be laminated. If necessary, the insulator layer can be subjected to surface treatment such as hydrolysis, corona discharge, low temperature plasma, physical roughening, and easy adhesion coating treatment.

  The formation of the conductor pattern is generally performed by either the subtractive method or the additive method, but any of them may be used in the present invention.

  In the subtractive method, a metal plate such as copper foil is bonded to the insulator layer with an insulating adhesive, or a precursor of the insulator layer is laminated on the metal plate, and the insulator layer is formed by heat treatment or the like. A pattern is formed by etching the material produced in (1) by chemical treatment. Specific examples of the material include rigid or copper-clad material for flexible printed circuit boards, TAB tape, and the like. Among them, a copper-clad material for a flexible printed board and a TAB tape are preferably used in which at least one polyimide film is an insulator layer and a copper foil is a conductor pattern.

  In the additive method, a conductor pattern is directly formed on the insulator layer by electroless plating, electrolytic plating, sputtering, or the like. In either case, the formed conductor may be plated with a metal having high corrosion resistance to prevent corrosion. Further, via holes may be formed in the wiring board layer as necessary, and conductor patterns formed on both surfaces may be connected by plating.

  (B) The layer in which the conductor pattern is not formed is a uniform layer substantially independent of the wiring substrate layer (C) or the adhesive layer (C) composed of the (A) insulator layer and the conductor pattern. Reinforcing and dimensional stabilization of connection substrates (referred to as reinforcement plates or stiffeners), external and IC electromagnetic shielding, IC heat dissipation (referred to as heat spreaders, heat sinks), semiconductor integrated circuit connection substrates It provides functions such as imparting flame retardancy and imparting distinctiveness according to the shape of the substrate for connecting a semiconductor integrated circuit. Therefore, the shape is not limited to a layer shape, and for example, it may have a fin structure for heat dissipation. Any material may be used as long as it has the above functions, and the material is not particularly limited. Metals include copper, iron, aluminum, gold, silver, nickel, titanium, and stainless steel, inorganic materials include alumina, zirconia, soda glass, quartz glass, and carbon, and organic materials include polyimide, polyamide, and polyester. , Vinyl-based, phenol-based, and epoxy-based polymer materials. Moreover, the composite material by these combination can also be used. Examples thereof include a thin metal plated shape on a polyimide film, a polymer kneaded with carbon to give conductivity, and a metal plate coated with an organic insulating polymer. In addition, various surface treatments are not limited as in the case of the insulator layer included in the (A) wiring board layer.

  The substrate with a metal layer may have an adhesive layer and a metal layer in this order on at least one side of the substrate, and may each have an adhesive layer and a metal layer on both sides of the substrate. As a substrate, a metal substrate such as a copper plate, an aluminum plate, a nickel plate, a stainless steel plate, an aluminum alloy plate, or a copper alloy plate, a ceramic substrate such as alumina, silica, zirconium, silicone carbide, aluminum nitride, silicon nitride, or boron nitride, glass Examples thereof include a plastic substrate such as an epoxy resin containing cloth and BT resin. Examples of the metal layer include a metal foil, a metal plate, and the like, and those in which a metal thin film layer is formed by physical surface treatment such as sputtering, electrolysis, and electroless plating are also included. Examples of the metal foil include copper foil, aluminum foil, nickel foil, stainless steel foil, aluminum alloy foil, and copper alloy foil. Examples of the metal plate include a copper plate, an aluminum plate, a nickel plate, a stainless steel plate, an aluminum alloy plate, and a copper alloy plate as in the case of the metal substrate. The metal foil, the metal plate, and the metal thin film layer are thinner than the substrate, and when used in combination with the metal substrate, the type of metal may be the same or different.

  An example is given and demonstrated about the manufacturing method of a board | substrate with a metal layer.

First, from the electronic device adhesive sheet of the present invention, peeling off the protection film layer, obtained substrate, the adhesive layer of the adhesive sheet for electronic devices, a stack of metal layers. For example, in the case of an aluminum substrate with copper foil, the protective film layer of the adhesive sheet obtained in (b) above is peeled off, and the adhesive layer is laminated on the copper foil and the aluminum plate. At this time, it is preferable to heat to 80-200 degreeC. Alternatively, it may be laminated only on either the copper foil or the aluminum plate, and only the aluminum plate or the copper foil may be overlaid without laminating the other side.

  Next, the laminate is pressurized at 0.1 MPa or more to cure the adhesive layer. For example, the copper foil, the adhesive layer, and the aluminum laminate can be heated and cured at 120 to 200 ° C. for 1 to 8 hours to heat and cure the adhesive layer to obtain an aluminum substrate with copper foil. The heat curing of the adhesive layer is preferably performed under a pressure condition of 0.1 MPa or more. Preferably it is 0.5PMa or more, More preferably, it is 1.0MPa or more. By curing the adhesive layer under heat and pressure conditions, the thermal conductivity and adhesive force can be further improved. For heat and pressure, a pressure vessel may be used, or a press device may be used.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. First, an evaluation method performed in each example will be described.

  (1) Peeling adhesive force: One protective film of an adhesive sheet having an adhesive layer thickness of 50 μm was peeled off on SUS304 having a thickness of 0.35 mm and laminated under conditions of 130 ° C. and 1 MPa. Thereafter, the other protective film of the adhesive sheet obtained by laminating a polyimide film (thickness 75 μm: “UPILEX” (registered trademark) 75S, manufactured by Ube Industries Co., Ltd.) on the previous SUS is peeled off at 130 ° C. and 1 MPa. After laminating, heat treatment was performed at 170 ° C. for 2 hours under 0.5 MPa pressure to prepare a sample for evaluation. After slitting the polyimide film to a width of 5 mm, the polyimide film having a width of 5 mm was peeled at a rate of 50 mm / min in the 90 ° direction, and the adhesive force at that time was measured. Here, the adhesive force is preferably 5 N / cm or more from the viewpoint of processability, handling properties, and reliability of the semiconductor device.

(2) Shear adhesive strength: One protective film layer of an adhesive sheet having an adhesive layer thickness of 50 μm is peeled off, and the adhesive layer is placed on a copper plate (20 mm × 20 mm) having a thickness of 1.2 mm at 130 ° C. and 1 MPa. Laminated. Next, the protective film on the opposite side of the adhesive sheet was peeled off, and a copper plate (5 mm × 30 mm) of the same thickness was laminated at 130 ° C. and 1 MPa to prepare a laminate of copper plate / adhesive layer / copper plate. Subsequently, it was heat-cured by the following two-level methods, and tensile shear adhesive strength was measured with Tensilon at a speed of 5 mm / min.
(A) Air atmosphere heating: Heat treatment was performed at 170 ° C. for 2 hours in an air atmosphere in an oven.
(B) Press heating: The laminate was set in a press machine, and pressure cured at 170 ° C. for 2 hours at 3 MPa.

(3) Thermal conductivity: An adhesive thin film having a thickness of 200 μm to 500 μm was prepared using the adhesive solution described in each of the examples and comparative examples, and heat cured by the following two levels of methods.
(A) Air atmosphere heating: Heat treatment was performed in an oven at 170 ° C. for 2 hours.
(B) Press heating: The laminate was set in a press machine, and pressure cured at 170 ° C. for 2 hours at 3 MPa.

  Subsequently, thermal diffusivity was measured in a measurement temperature of 100 ° C., irradiation light: ruby laser light, and vacuum atmosphere with a thermal constant measuring device TC-7000 manufactured by ULVAC-RIKO. Moreover, the density of the adhesive composition was measured by Archimedes method, the specific heat was measured by DSC method, and the thermal conductivity was calculated from these parameters.

Examples 1-23, Comparative Examples 1-8
The following thermally conductive filler and inorganic particles were weighed so as to have the blending ratios of Examples and Comparative Examples described in Tables 1 to 3, and mixed in a mixer for 2 minutes. Thereafter, the silane coupling agent was sprayed with a spray while further mixing the thermally conductive filler and the inorganic particles, and silane treatment was performed. Thereafter, an epoxy resin, a curing agent, a thermoplastic resin, and other additives are blended so as to have the compositions shown in Tables 1 to 3, respectively, and DMF / monochlorobenzene / MIBK equivalents to a solid content concentration of 35% by weight. The mixture was stirred and dissolved in a mixed solvent at 40 ° C. to prepare an adhesive solution. This adhesive solution was applied to a 38 μm-thick polyethylene terephthalate film with a silicone release agent (“Film Vina” (registered trademark) GT manufactured by Fujimori Kogyo Co., Ltd.) with a bar coater to a dry thickness of about 50 μm. Then, the film was dried at 120 ° C. for 5 minutes, and a protective film was bonded to produce an adhesive sheet of the present invention. The raw materials used in the examples are as follows.

<Epoxy resin>
Epoxy resin 1: bisphenol A type epoxy (“Epicoat” (registered trademark) 828, epoxy equivalent 190, manufactured by Japan Epoxy Resins Co., Ltd., liquid at normal temperature, viscosity at 25 ° C .: 14 Pa · s)
Epoxy resin 2: bisphenol A type epoxy (Epicoat 1001, epoxy equivalent 474, manufactured by Japan Epoxy Resin Co., Ltd., solid at room temperature)
Epoxy resin 3: o-cresol novolac type epoxy (EOCN-1020, epoxy equivalent 200, manufactured by Nippon Kayaku Co., Ltd., solid at normal temperature)
Epoxy resin 4: dicyclopentadiene type (HP-7200, epoxy equivalent: 260, manufactured by Dainippon Ink & Chemicals, Inc., solid at normal temperature)
Epoxy resin 5: bisphenol A type epoxy (Epicoat 827, epoxy equivalent 190, manufactured by Japan Epoxy Resins Co., Ltd., liquid at normal temperature, viscosity at 25 ° C .: 10 Pa · s)
<Curing agent>
Curing agent: Phenol novolak resin (PSM4326, hydroxyl group equivalent 105, manufactured by Gunei Chemical Industry Co., Ltd.)
<Thermoplastic resin>
Thermoplastic resin 1: SGP-3 (manufactured by Nagase ChemteX Corp.): Epoxy group-containing acrylic rubber thermoplastic resin mainly composed of butyl acrylate 2: SG-280DR (manufactured by Nagase ChemteX Corp.): butyl acrylate Group-containing acrylic rubber-containing acrylic rubber thermoplastic resin 3: PNR-1H (manufactured by JSR Corporation): carboxyl group-containing NBR
<Thermal conductive filler>
(D1)
Thermally conductive filler 1: Aluminum nitride powder (H grade, average particle size 1.7 μm, manufactured by Tokuyama Corporation)
Thermally conductive filler 2: Water resistant aluminum nitride powder (MAN-2A, average particle size 1.3 μm, manufactured by Mitsui Chemicals, Inc.)
Thermally conductive filler 3: Silica coated aluminum nitride filler (TOYALNITE FL
B, average particle size 3 μm, manufactured by Toyo Aluminum Co., Ltd.)
Thermally conductive filler 4: Boron nitride powder (HGPE, average particle size 1.9 μm, manufactured by Denki Kagaku Kogyo Co., Ltd.)
Thermally conductive filler 5: Aluminum nitride powder (FLA, average particle size 8 μm, manufactured by Toyo Aluminum Co., Ltd.)
Thermally conductive filler 6: Aluminum nitride powder (FAN-f30, average particle size 20 μm, manufactured by Furukawa Electronics Co., Ltd.)
(D2)
Thermally conductive filler 7: spherical alumina powder (AO-502, average particle size 0.7 μm, manufactured by Admatechs)
<Inorganic particles>
Inorganic particles 1: spherical silica (SO-C5, average particle size 1.6 μm, manufactured by Admatechs)
Inorganic particles 2: spherical silica (SO-C2, average particle size 0.5 μm, manufactured by Admatechs Co., Ltd.)
<Curing catalyst>
Curing catalyst: Triphenylphosphine <Silane coupling agent>
Silane coupling agent 1: 3-glycidoxypropyltrimethoxysilane Silane coupling agent 2: N-phenyl-3-aminopropyltrimethoxysilane

  As is apparent from Tables 1 to 3, the adhesive sheet obtained according to the present invention has a high thermal conductivity and has a sufficient adhesive force after thermosetting.

Claims (6)

An adhesive sheet for electronic equipment having at least an adhesive layer and a peelable protective film layer, wherein the adhesive layer comprises (A) an epoxy resin, (B) a curing agent, (C) a thermoplastic resin, and (D) (D2) an inorganic powder having an average particle size of 1 to 10 μm selected from the group consisting of aluminum nitride, silicon nitride and boron nitride, and (d2) an average It consists spherical alumina powder having a particle size of 0.01 to 1 [mu] m, the content ratio of d1: d2 is 95 in a weight ratio: 5 to 50: 50 der is, the adhesive layer in the (D) a thermally conductive filler 35 The adhesive sheet for electronic devices characterized by containing 0.5-77.8 volume%, (D) The heat conductive filler is surface-treated with the silane coupling agent . 2. The adhesive sheet for electronic equipment according to claim 1, wherein (D) the heat conductive filler is contained in the adhesive layer in an amount of 40 to 75% by volume. The adhesive sheet for electronic equipment according to claim 1, wherein the epoxy resin contains an epoxy resin having a viscosity at 25 ° C. of 25 Pa · s or less. The silane coupling agent is 3-glycidoxypropyltrimethoxysilane or N- phenyl-3-aminopropyl adhesive sheet for electronic equipment according to claim 1, characterized in that it contains trimethoxysilane. An electronic component using the adhesive sheet for electronic equipment according to claim 1. At least one surface adhesive layer of the substrate, a manufacturing method of the metal layer-coated substrate having a metal layer in this order, (a) according to claim 1-4 adhesive sheet or RaTamotsu protecting film layer for an electronic device according to any one A step of obtaining a laminate of a substrate, an adhesive layer of the adhesive sheet for electronic devices, and a metal layer, (b) a step of pressing the laminate at 0.1 MPa or more and curing the adhesive layer, The manufacturing method of the board | substrate with a metal layer characterized by having.