JP2008130824A - Adhesive sheet for buildup type multilayer printed wiring board, and buildup type multilayer printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further thin a semiconductor device, and to provide an extremely thin multilayer plate which does not cause troubles due to heat in its manufacturing or heat generated from an element itself, and to provide an adhesive sheet for a buildup type multilayer printed wiring board. <P>SOLUTION: An adhesive sheet 3 is formed by laminating an adhesive layer 3b in one side or both sides of a wholly aromatic polyamide film 3a. In the adhesive sheet 3 and the buildup type multilayer printed wiring board 1, the thickness of the wholly aromatic polyamide film 3a is 3 to 15 μm, the total thickness of the adhesive sheet 3 is 5 to 45 μm and heat conductivity of a hardening body of the adhesive sheet 3 is 1 W/m K or more. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention uses a build-up type multilayer printed wiring board adhesive sheet excellent in heat dissipation of heat generated from a semiconductor element and suitable for manufacturing a multilayer printed wiring board having high density mounting and high density wiring, and the adhesive sheet. The present invention relates to a build-up type multilayer printed wiring board.

  With the downsizing and speeding up of electronic devices, high-density mounting and high-density wiring of multilayer printed wiring boards are being promoted, and pattern thinning and through-hole diameters are progressing. Further, the build-up type multilayer printed wiring board developed and put into practical use based on these technical issues is further refined.

  The inner layer board that is the core of the build-up type multilayer printed wiring board uses a double-sided board that uses glass cloth as the base material, and the build-up layer that is the outer layer is a system that coats the resin, a system that stacks the resin film It was formed by a method such as a method of overlapping copper foils with resin.

  In that case, as the insulating resin for the build-up layer, a photo-curing insulating resin such as epoxy acrylate is used in the photo via method, while a thermosetting insulating resin such as a modified epoxy resin is used in the laser via method. In either case, the base material is not used for the fine pattern formation in the built-up insulating resin layer (see, for example, Patent Documents 1 and 2).

  On the other hand, semiconductor devices to be mounted have been reduced in size and thickness, and further downsizing due to high-speed data processing, high functionality, and large capacity. For example, the outer diameter is reduced to the size of a semiconductor chip (element). A so-called chip size package (CSP) is known, which is a semiconductor package equivalent to or slightly larger than the above.

Also, devices using high-power elements such as power transistors and power integrated circuit devices are switching regulators for power supplies for electronic circuits such as office automation equipment and portable electronic devices, notebook PCs, mobile phone charging circuits, and liquid crystal panels. In recent years, its application has been rapidly expanding (see, for example, Patent Document 3).
JP 2003-025494 A JP 2000-036666 A JP 10-163372 A

  However, the conventional build-up type multilayer printed wiring board has an adhesive sheet for building up that has a predetermined thickness or more in consideration of ease of handling, etc., which makes the printed wiring board itself thick. It was a thing.

  Further, when high-power elements are used, these semiconductor elements have a high output, so they generate a large amount of heat, and countermeasures against heat have been a major technical issue.

  Accordingly, an object of the present invention is to provide an ultra-thin multilayer board and an adhesive sheet for a build-up type multilayer printed wiring board in which a semiconductor device is further thinned and does not cause defects due to heat generated from the manufacturing process or the element itself. To do.

  As a result of intensive studies, the present inventors have used a wholly aromatic polyimide film, and the adhesive sheet is configured to have a predetermined thickness and a predetermined thermal conductivity, thereby being extremely thin and excellent in heat dissipation. The present inventors have found that a build-up type multilayer printed wiring board can be obtained and have completed the present invention.

  That is, the build-up type multilayer printed wiring board adhesive sheet of the present invention is an adhesive sheet obtained by laminating an adhesive layer on one or both sides of a wholly aromatic polyamide film, and the thickness of the wholly aromatic polyamide film is 3 to 15 μm, the total thickness of the adhesive sheet is 5 to 45 μm, and the thermal conductivity of the cured adhesive sheet is 1 W / m · K or more.

  According to the adhesive sheet for a build-up multilayer printed wiring board of the present invention, it is possible to manufacture a build-up type printed wiring board with a small thickness and is excellent in heat dissipation of heat generated from a semiconductor chip. The printed wiring board manufactured by the method can suppress a temperature rise even when a high-power semiconductor chip is used, and can be operated more stably than in the past.

  Embodiments of the present invention will be described below.

  The build-up type multilayer printed wiring board adhesive sheet of the present invention is an adhesive sheet configured by laminating an adhesive layer on one side or both sides of a wholly aromatic polyamide film.

  Since the film used here constitutes the insulating layer of the printed wiring board by build-up, it is required to be an electrically insulating film. In the present invention, a wholly aromatic polyamide film is used. . This wholly aromatic polyamide film is composed of a wholly aromatic polyamide resin, which is an engineering plastic with high heat resistance and high strength. For example, it is copolycondensed from p-phenylenediamine and terephthalic acid chloride. An aramid resin such as a para-aramid resin obtained by the above method.

  The total aromatic polyamide film has a thickness of 15 μm or less, preferably 3 to 15 μm, in order to reduce the thickness and size. When the thickness of the film is less than 3 μm, the mechanical properties of the film are lowered, so that the workability during production and processing is remarkably deteriorated and the production yield is lowered, and when the thickness is more than 15 μm, the film is hardened. It becomes brittle and the flexibility tends to decrease.

  In order to sufficiently obtain the effects of the present invention, the wholly aromatic polyamide film used in the present invention has a tensile modulus of 3000 MPa or more, preferably 6000 to 25000 MPa, and a thermal expansion coefficient of 20 ppm / ° C. or less, preferably − A wholly aromatic polyamide film having physical properties of 10 to 20 ppm / ° C. is preferred. Specific products include Aramika (manufactured by Teijin Advanced Films, Inc., trade name) and the like. This aramica has the characteristics that the glass transition temperature is 355 ° C., the tensile elastic modulus is 15000 MPa, and the thermal expansion coefficient is ± 1 ppm / ° C.

  In addition, as a measuring method of the physical property of the above-mentioned wholly aromatic polyamide film, the glass transition temperature is a dynamic thermomechanical analysis DMA method (temperature rising condition 20 ° C./min), the tensile elastic modulus is ASTM D882, and the thermal expansion coefficient is a thermal machine. It is determined by analytical TMA method (temperature rising condition 20 ° C./min).

  Further, one or both surfaces of these wholly aromatic polyamide films may be subjected to a surface treatment. As the surface treatment, a low temperature plasma treatment, a corona discharge treatment, a sand blast treatment or the like is suitable. When the surface treatment of the film is performed, the adhesion at the interface between the film and the adhesive is improved, and the reliability as a multilayer printed wiring board is improved.

  The adhesive composition constituting the adhesive layer in the adhesive sheet of the present invention comprises an epoxy resin, a curing agent for epoxy resin, a curing accelerator and an inorganic filler as essential components, but further, if necessary, an elastomer, aging An inhibitor, fine powder inorganic filler or organic filler, pigment and the like can be added and blended.

  Examples of the epoxy resin used in the present invention include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, isocyanurate type epoxy resin, and hydantoin type epoxy. Resin, alicyclic epoxy resin, biphenyl type epoxy resin, polyfunctional epoxy resin, and the like. Specific examples include Epicoat 1001 (trade name, manufactured by Japan Epoxy Resin Co., Ltd.), Epicoat 1004 (Japan). Epoxy Resin Co., Ltd., trade name) and the like, and these can be used alone or in admixture of two or more.

  Moreover, as a hardening | curing agent of the said epoxy resin of the epoxy resin composition used for this invention, the hardening | curing agent of a well-known epoxy resin can be used. Examples include aliphatic amine curing agents, alicyclic amine curing agents, aromatic amine curing agents, acid anhydride curing agents, phenol novolac, dicyandiamide, boron trifluoride amine complex salts, and the like. Alternatively, two or more kinds can be mixed and used.

  The blending amount of these curing agents is preferably set in the range of 0.03 to 0.4 equivalents with respect to 1 equivalent of the epoxy resin. If the amount is less than 0.03 equivalent, sufficient curing of the epoxy resin cannot be obtained, and other properties, solvent resistance, electrical properties, etc. also decrease. If the amount exceeds 0.4 equivalent, the adhesiveness and solder heat resistance decrease. To do.

  Furthermore, examples of the curing accelerator used in the present invention include imidazoles, BF complexes, tertiary amines, triphenylphosphine, and the like, and these can be used alone or in admixture of two or more.

  Furthermore, the epoxy resin composition of the present invention preferably contains an elastomer. Examples of the elastomer include acrylonitrile butadiene rubber, carboxyl group-containing acrylonitrile butadiene rubber, vinyl group-containing acrylonitrile butadiene rubber, butadiene rubber, acrylonitrile butadiene rubber, carboxyl group. Containing acrylonitrile butadiene rubber and the like can be mentioned, and these can be used alone or in admixture of two or more.

  The components constituting these adhesive compositions are mixed using a pot mill, ball mill, roll mill, homogenizer, super mill or the like.

  Further, these adhesive compositions include silica, silicon carbide, aluminum nitride, silicon nitride having an average particle size of 0.1 to 10 μm, preferably 0.1 to 4.0 μm, in order to improve thermal conductivity. It is preferable to contain 1% by volume to 33% by volume of a single inorganic filler such as alumina or aluminum hydroxide, or a mixture of two or more thereof, with respect to the adhesive composition.

  Among these, aluminum nitride, silicon carbide, and silicon nitride are particularly preferable in that a build-up material having excellent thermal conductivity can be formed as compared with other inorganic fillers.

  At this time, if the average particle size of the inorganic filler is less than 0.1 μm, the viscosity of the adhesive composition will increase too much, and if a solvent is added to avoid this increase in viscosity, Time is required for drying, and as a result, work efficiency such as a decrease in coating speed is deteriorated. On the other hand, if the average particle diameter exceeds 10 μm, the filter intended to remove foreign matter is likely to be clogged, resulting in a decrease in productivity.

  The blending amount of the inorganic filler is preferably 1 to 33% by volume with respect to the adhesive composition. Each of these components can be uniformly dissolved using a solvent such as methyl ethyl ketone (MEK) / cellosolve to easily produce an adhesive composition for build-up substrates.

  First, the above adhesive composition can be appropriately dissolved in the above solvent in consideration of a desired viscosity and the like.

  The solid content concentration when this resin composition is dissolved in a solvent may be 10 to 45% by weight, preferably 20 to 35% by weight. If the solid content concentration exceeds 45% by weight, the coating property deteriorates due to an increase in viscosity or a decrease in compatibility, the workability decreases, and if it is less than 10% by weight, uneven coating tends to occur. Since the amount increases, problems such as environmental aspects and uneconomical factors arise.

  The build-up type printed wiring board adhesive sheet of the present invention uses the wholly aromatic polyamide film as an insulating film substrate, and the adhesive composition is applied to one or both surfaces of the substrate under the conditions described later. It is obtained by drying and semi-curing the adhesive composition to the B stage state.

  The adhesive composition was made into a semi-cured state by removing the solvent by drying, and then a release material such as a release paper or a release film was applied to the adhesive application surface with a heating roll at a linear pressure of 2 to 200 N / cm, 60 to You may make it crimp at 150 degreeC.

  Moreover, in order to further harden the adhesive layer of the obtained adhesive sheet with a release material, it is heated and aged at a temperature of 30 to 200 ° C. for 1 minute to 150 hours. The amount of resin flow (resin flow) during hot pressing may be adjusted as appropriate.

  At this time, the thickness of the adhesive sheet, that is, the total thickness of the wholly aromatic polyamide film and the adhesive layer is 5 to 45 μm, preferably 5 to 20 μm. If the thickness is less than 5 μm, the strength is significantly reduced, making it difficult to fabricate a flexible printed wiring board. If the thickness is more than 45 μm, the cost is increased, the brittleness is reduced, the flexibility is reduced, and space saving and fine patterning are required. Will not be appropriate for the current situation.

  In applying and drying the above adhesive composition on an insulating film substrate, a temperature of 80 to 180 ° C. is preferable because the organic solvent component of the adhesive composition is insufficient when this heat drying is insufficient. Therefore, voids are generated after build-up molding, and reliability such as adhesion and solder heat resistance is lowered. In addition, when heated and dried excessively, the B-stage state of the surface of the adhesive composition proceeds, and the pot life is reduced, the metal foil after build-up molding, and the adhesion with the insulating film are uneven, As a result, large and small unevenness occurs in the peel strength, solder heat resistance, and dielectric properties of the metal foil.

  Next, the adhesive sheet manufactured in this way is built up to a core material as a buildup material. In the case of a build-up material for a double-sided adhesive layer, a conductive layer can be formed by laminating metal foil or the like. By laminating metal foils to form a pressure-receiving body and heating and pressing the pressure-receiving body, the adhesive composition of the build-up material can be cured to obtain a multilayer laminate.

  As the metal foil, a copper foil, an aluminum foil, or the like can be used, but a copper foil is preferable in consideration of subsequent processes such as circuit formation. The thickness of this copper foil laminated | stacked with an electrically insulating film through the adhesive bond layer used for this invention is 5-15 micrometers, Preferably, it is 6-14 micrometers. If the thickness of the copper foil is less than 5 μm, the mechanical properties of the copper foil are lowered and workability is remarkably lowered. If the thickness is more than 15 μm, it becomes difficult to sharpen the copper edge during etching, and a fine pattern of 100 μm or less. It is extremely difficult to adjust the circuit pitch to the target when manufacturing the circuit. Examples of the copper foil include rolled copper foil, electrolytic copper foil, and the like, which can be appropriately selected and used according to the application.

  In addition, as a method for forming the conductive layer, a known thin film forming method, for example, a sputtering method, a vacuum deposition method, an electroless plating, an electrolytic plating, or the like can be given, and a metal foil layer is formed using these methods. Build-up materials can also be obtained.

In addition, since the above pressurization is performed for joining the metal foil and the build-up material and adjusting the thickness, the pressurization conditions can be selected as necessary, but the epoxy resin and the curing agent for this epoxy resin Since the crosslinking reaction mainly depends on the reaction characteristics of the curing agent, it is necessary to select a heating temperature and a heating time according to the type of the curing agent. For example, in general, the heating operation is performed at a temperature of 150 to 300 ° C., a pressure of 4.9 MPa (50 kg / cm ² ), and a time of about 10 to 60 minutes.

  The build-up type multilayer printed wiring board according to the present invention uses a double-sided metal foil-clad laminate as a core material. First, the double-sided metal foil-clad laminate is subjected to a circuit forming process such as a subtractive method. Thus, circuit patterns on both sides are formed. Next, a buildup layer is formed on one side of the laminate on which the circuit pattern is formed, using the adhesive sheet for buildup type multilayer printed wiring boards of the present invention.

  This build-up layer is formed by laminating a metal foil such as a copper foil on the surface of the laminated board on which the circuit pattern is formed via the above-mentioned adhesive sheet for a multi-layer printed wiring board, and then laminating them by heating and pressing. Can be formed.

  After forming a multilayer laminated board in this way, the circuit formation process similar to the above is performed to form a circuit pattern on the metal foil of the build-up layer and signal transmission for connecting the circuit patterns of a plurality of layers A via hole (plating through hole) is formed to make the circuit conductive. The build-up layer may be formed only on one side of the laminated board on which a circuit pattern is formed as necessary.

  In addition, via holes can be formed at predetermined positions with the release films attached to both sides of the build-up material by a known method (for example, a laser drilling method such as a carbon dioxide laser, an excimer laser, or a drilling method using a drill). A member for a circuit board connecting material in which a through-hole is formed and filled with a known conductive composition by a method such as printing or die coating can be prepared.

  Here, it demonstrates using the conceptual diagram of this invention and the conventional buildup type | mold multilayer printed wiring board, respectively. FIG. 1 shows a build-up type multilayer printed wiring board 1 according to the present invention, which is composed of a core material 2 and a plurality of adhesive sheets 3 laminated on both sides of the core material. Copper wiring patterns 4 are provided between the adhesive sheets and between the adhesive sheets. These wiring patterns are connected to each other through through holes, via holes, or the like. Moreover, the adhesive sheet 3 of the present invention has a configuration in which an adhesive layer 3b is laminated on a wholly aromatic polyamide film 3a, and this forms an insulating layer in a printed wiring board.

  FIG. 2 shows a conventional build-up type multilayer printed wiring board 11. The multilayer printed wiring board is composed of a core material 12 and an adhesive sheet 13 in which a plurality of sheets are laminated on both sides of the core material as in the present invention. A copper wiring pattern 14 is provided between the core material and the adhesive sheet, and between the adhesive sheets. These wiring patterns are interlayer-connected by through holes, via holes and the like. Here, the adhesive sheet 13 is composed of only an adhesive layer film.

  The invention of the present application is superior in handling, strength, insulation, conductivity, etc., although the adhesive sheet is thinner than the conventional one. When manufacturing printed wiring boards having the same configuration, the printed wiring is thinner and more compact. Since a plate can be obtained and heat dissipation can be improved, the device can be stably operated even when a semiconductor chip is mounted to form a semiconductor device.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited by these Examples. In the following examples and comparative examples, “parts” means “parts by mass”.

(Example 1)
Bisphenol A type epoxy resin Epicoat 1001 (manufactured by Japan Epoxy Resin, trade name; epoxy equivalent 475) 43.5 parts, 4,4′-diaminodiphenylsulfone (amine equivalent 62) 5.7 parts, 2-ethyl-4- 0.2 parts of methylimidazole, 10 parts of cyclophenoxyphosphazene oligomer (melting point 100 ° C.) and 20 parts of aluminum nitride having an average particle diameter of 1.5 μm as an inorganic filler, MEK (methyl ethyl ketone) / MCA (methyl cellosolve acetate) = 6 / 4 was dissolved in a mixed solvent of No. 4 to obtain a resin composition, and this resin composition was bonded to both sides of a PPTA (polyparaphenylene terephthalamide) aramid film 4 μm thick (manufactured by Teijin Advanced Films, trade name: Aramika 042RC) after drying. The thickness of the agent layer is 8μm and 10μ respectively Coating and drying a roll coater so that, to produce a total thickness 22μm buildup type multilayer printed wiring board adhesive sheet.

Furthermore, the obtained adhesive sheet and the copper foil having a thickness of 12 μm were laminated on both sides of a copper clad laminate in which a copper foil having a thickness of 12 μm was bonded to both sides of a core material having a thickness of 80 μm. Build up by heating and pressurizing at 0.0 MPa, and laminate this on both sides of the copper-clad laminate so that there are two build-up layers on each side. Furthermore, a 4 μm thick aramid film (manufactured by Teijin Advanced Film, product) Name: Aramica 042RC) was laminated on both sides with a coverlay provided with a 10 μm thick adhesive layer to produce a 6-layer build-up type multilayer printed wiring board.
The same adhesive as the adhesive sheet was used for the adhesive layer of the coverlay. This point was also performed in the following examples and comparative examples using the same adhesive as the adhesive sheets used in the examples and comparative examples.

(Example 2)
An adhesive sheet and a multilayer printed wiring board were produced in the same manner as in Example 1 except that alumina having an average particle diameter of 1.0 μm was used as the inorganic filler.

(Example 3)
An adhesive sheet and a multilayer printed wiring board were produced in the same manner as in Example 1 except that silicon nitride having an average particle size of 3.0 μm was used as the inorganic filler.

Example 4
An adhesive sheet and a multilayer printed wiring board were produced in the same manner as in Example 1 except that silica having an average particle diameter of 0.7 μm was used as the inorganic filler.

(Example 5)
An adhesive sheet and a multilayer printed wiring board were produced in the same manner as in Example 1 except that aluminum hydroxide having an average particle size of 1.1 μm was used as the inorganic filler.

(Comparative Example 1)
A 25 μm thick polyimide film (manufacturer: Toray DuPont, trade name: Kapton 100EN) is used as the base material, the thickness of the adhesive layers provided on both sides thereof is 10 μm, the total thickness of the adhesive sheet is 45 μm, and the cover Adhesive sheet and multilayer print in the same manner as in Example 1 except that a 25 μm thick polyimide film (trade name: Kapton 100EN) provided with a 10 μm thick adhesive layer was used as a ray. A wiring board was manufactured.

(Comparative Example 2)
Aluminum hydroxide having an average particle diameter of 1.1 μm is used as an inorganic filler, and a glass cloth (manufacturer: Asahi Sieber, trade name: A106 / AS440) having a thickness of 30 μm is used as the base material, and this is impregnated with an adhesive. An adhesive sheet and a multilayer printed wiring board were produced in the same manner as in Example 1 except that a prepreg (adhesive sheet) having a thickness of 40 μm was provided and a resist layer having a thickness of 45 μm was provided instead of the coverlay.

(Comparative Example 3)
An adhesive sheet, a multilayer, was formed in the same manner as in Example 1 except that an adhesive sheet was formed with an adhesive layer thickness of 40 μm without using a base material, and a resist layer with a thickness of 45 μm was provided instead of the coverlay. A printed wiring board was manufactured.

(Comparative Example 4)
A polyimide film with a thickness of 12.5 μm (manufacturer: Toray DuPont, product name: Kapton 50EN) was used as the base material, the total thickness of the adhesive sheet was 30.5 μm, and a polyimide film with a thickness of 12.5 μm (Toray) An adhesive sheet and a multilayer printed wiring board were produced in the same manner as in Example 1 except that a product having a 10 μm thick adhesive layer provided on DuPont's product name: Kapton 50EN) was used.

(Comparative Example 5)
An aramid film (manufacturer: Teijin Advanced Film, trade name: Aramika 160RC) is used as the substrate, the total thickness of the adhesive sheet is 34 μm, and a 16 μm thick aramid film (manufactured by Teijin Advanced Film, An adhesive sheet and a multilayer printed wiring board were produced in the same manner as in Example 1 except that a product having an adhesive layer having a thickness of 16 μm was used.

(Test example)
The adhesive layer of the adhesive sheets manufactured in Examples and Comparative Examples was cured, and the characteristics including the elastic modulus, thermal conductivity, thermal resistance, and dielectric strength of the adhesive sheets were measured. In addition, interlayer insulation reliability and thermal resistance of the obtained 6-layer multilayer printed wiring board were measured. These results are shown together in Tables 1 and 2.

* 1: Obtained by the TMA method using Seiko Instruments Inc., trade name: TMA / SS6600 under the conditions of [elastic modulus of adhesive] and 30 to 250 ° C. (temperature increase of 10 ° C./min).
* 2: [Tensile strength of substrate], determined according to JIS C 2328.
* 3: [Tensile modulus of base material], determined according to ASTM D882.
* 4: [Thermal conductivity of adhesive sheet], measured at room temperature by a laser flash method using Kyoto Electronics Industry Co., Ltd., trade name: LFA-502.
* 5: [Thermal resistance of the adhesive sheet], calculated from the thermal conductivity obtained in * 3 and the thickness of the adhesive sheet.
* 6: [Dielectric withstand voltage of adhesive sheet], determined according to JIS C 3005.
* 7: [Interlayer insulation reliability of 6-layer substrate] The interlayer insulation resistance after 1000 hr treatment of the test piece under the condition of 85 ° C / 85% RH / 12V application was measured. When the measured value was 10 ⁻¹² Ω or more, it was evaluated as “◯”, when it was 10 ⁻¹⁰ Ω or more and less than 10 ⁻¹² Ω, Δ when it was less than 10 ⁻¹⁰ Ω.
* 8: [Thermal resistance of the 6-layer substrate], calculated by the thermal conductivity of the 6-layer substrate and the thickness of the 6-layer substrate in the same manner as the thermal resistance of * 4.

It is sectional drawing of the buildup type multilayer printed wiring board of this invention. It is sectional drawing of the conventional buildup type multilayer printed wiring board.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,11 ... Build-up type multilayer printed wiring board 2,12 ... Core material (double-sided copper clad laminated board), 3,13 ... Adhesive sheet, 3a ... Whole aromatic polyamide film, 3b ... Adhesive layer, 4,14 ... Wiring pattern

Claims (6)

  An adhesive sheet obtained by laminating an adhesive layer on one or both sides of a wholly aromatic polyamide film, wherein the wholly aromatic polyamide film has a thickness of 3 to 15 μm and the adhesive sheet has a total thickness of 5 to 45 μm. And the heat conductivity of the hardening body of the said adhesive sheet is 1 W / m * K or more, The buildup type multilayer printed wiring board adhesive sheet characterized by the above-mentioned.   The buildup type multilayer printed wiring board adhesive sheet according to claim 1, wherein the adhesive layer has a thickness of 3 to 15 µm. The adhesive layer is
(A) at least one polyepoxide compound;
(B) an epoxy curing agent;
(C) an epoxy curing accelerator;
(D) an inorganic filler;
The adhesive sheet for build-up type multilayer printed wiring boards according to claim 1 or 2, wherein the adhesive sheet is formed of a resin composition having an essential component.   The (D) inorganic filler comprises at least one selected from silica, aluminum nitride, silicon carbide, silicon nitride, alumina and aluminum hydroxide, and has an average particle size of 0.1 to 10 μm. The adhesive sheet for buildup type multilayer printed wiring boards according to any one of claims 1 to 3.   5. The buildup type multilayer printed wiring board adhesive sheet according to claim 1, wherein the wholly aromatic polyamide film has a tensile elastic modulus of 3000 MPa or more.   A build-up type multilayer printed wiring board using the adhesive sheet for build-up multilayer printed wiring boards according to any one of claims 1 to 5.

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