JP2012191108A - Prepreg for buildup - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide both improvement in embedding characteristic of an inner layer circuit and precision in thickness.SOLUTION: A prepreg 1 for buildup includes a fiber base material 2 and resin layers 3 and 4 provided on both surfaces of the fiber base material 2, and is compatible with IPC-TM-650 Method 2.3.17, to show the resin flow of 15-50 wt.% when measured after heated and pressurized for five minutes under the condition of 171±3°C, 1380±70 kPa.

Description

  The present invention relates to a prepreg for buildup.

  2. Description of the Related Art A manufacturing technique of a laminated wiring board by a build-up method in which insulating layers and conductor layers are alternately stacked on a circuit board is known.

  For example, in Patent Document 1, a laminate material composed of a prepreg and a metal foil impregnated with a thermosetting resin varnish on a paper or cloth base material is sandwiched between mirror plates, and a large number of layers are laminated, and a cushion material and a carrier material are interposed. In the method of manufacturing a thermosetting resin laminate formed by placing the heat plate between the heat plates and heating and pressing the heat plate, the cushion material has protrusions along each side formed on the surface side thereof. The manufacturing method of the thermosetting resin laminated board characterized by this is described. According to this method, since the protrusions along the sides are formed on the surface of the cushion material, the pressure at the outer peripheral edge of the laminated material is higher than that at the other parts during press molding, It is said that this resin hardly protrudes to the outside.

  Patent Document 2 discloses a resin composition layer surface of an adhesive film composed of a support base film and a resin composition layer on a patterned circuit board using a vacuum laminating apparatus that can be heated and pressurized. In the laminating method, an anti-smudge sheet smaller than the surface area of the adhesive film is provided between at least one press plate of the vacuum laminating apparatus and the support base film surface of the adhesive film, and the anti-smudge sheet is provided around the surface of the adhesive film. In any of the above points, it is described that the adhesive can be prevented from sticking out by being installed so as not to protrude outside.

JP-A-4-185408 JP 11-340625 A

  However, in the prepregs of Patent Documents 1 and 2, since the problem is to prevent the resin from protruding when applied to a vacuum laminator, it is difficult to ensure sufficient fluidity to embed circuit irregularities on the inner circuit board. It was done. On the other hand, these conventional prepreg laminates have a problem that voids remain between circuits. According to the confirmation of the present inventors, the resin flow of such a conventional prepreg is about 5 to 8% by weight, and the highest one is only 12% by weight. Therefore, the present inventors considered that the resin could not sufficiently follow the circuit irregularities, resulting in a decrease in embedding.

  However, when the fluidity of the resin composition constituting the resin layer of the prepreg is secured so that the circuit irregularities can be sufficiently embedded, the resin composition flows out too much during vacuum lamination. As a result, the thickness of the resulting laminated board varies. Thus, the improvement of the embedding property of the inner layer circuit and the improvement of the thickness accuracy were in a trade-off relationship.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a build-up prepreg that achieves both improvement in embedding of an inner layer circuit and improvement in thickness accuracy.

According to the present invention,
A fiber base and a resin layer provided on both sides of the fiber base;
According to IPC-TM-650 Method 2.3.17, the resin flow measured by heating and pressing for 5 minutes under the conditions of 171 ± 3 ° C. and 1380 ± 70 kPa is 15% by weight or more and 50% by weight or less. A build-up prepreg is provided.

Moreover, according to the present invention,
A core layer having a circuit forming surface on one or both sides;
A buildup layer laminated on the circuit forming surface of the core layer;
With
The build-up layer is provided with a laminated board formed by curing the build-up prepreg.

Moreover, according to the present invention,
The above laminate,
A semiconductor element mounted on the laminate,
A semiconductor device is provided.

Furthermore, according to the present invention,
A laminating step of laminating a prepreg for buildup on the circuit forming surface of the core layer having a circuit forming surface on one side or both sides under heat and pressure;
A smoothing step of smoothing the surface of the laminated prepreg for buildup to obtain a laminate;
A method of manufacturing a laminated board that continuously performs
In the laminating step, heating and pressurizing the core layer and the prepreg for buildup sandwiched between a pair of opposing metal plates,
As the build-up prepreg, there is provided a method for producing a laminated board using the build-up prepreg.

  According to this invention, in accordance with IPC-TM-650 Method 2.3.17, the resin flow measured by heating and pressurizing for 5 minutes under the conditions of 171 ± 3 ° C. and 1380 ± 70 kPa is 15% by weight or more. By doing so, a prepreg excellent in the embedding property of the inner layer circuit can be obtained. Moreover, when the upper limit of the resin flow is 50% by weight or less, the outflow of the resin layer from the prepreg can be suppressed when the prepreg is laminated and pressed. Therefore, when it is laminated on the core layer having the circuit forming surface, it is possible to realize a build-up prepreg that is excellent in embedding of the inner layer circuit and that can suppress the outflow of the resin layer from the prepreg during the lamination press.

  ADVANTAGE OF THE INVENTION According to this invention, the prepreg for buildup which can improve the embedding property of an inner layer circuit and the improvement of thickness precision is provided.

It is sectional drawing which showed typically the prepreg which concerns on embodiment. It is a figure explaining the method to measure the resin flow of the prepreg which concerns on an Example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

[Prepreg]
FIG. 1 is a diagram showing an example of a prepreg of the present invention. The prepreg 1 includes a fiber base 2 and resin layers 3 and 4 provided on both sides of the fiber base 2. The prepreg 1 can be formed by impregnating the fiber base 2 with a resin composition. Hereinafter, although the resin composition P used for the prepreg 1 is demonstrated, the resin composition which comprises the resin layers 3 and 4 may mutually be the same, and may differ, respectively.

  The resin composition P used for the prepreg 1 contains (A) an epoxy resin. (A) As an epoxy resin, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol E type epoxy resin, bisphenol M type epoxy resin, bisphenol P type epoxy resin, bisphenol Z type epoxy Bisphenol type epoxy resin such as resin, novolac type epoxy resin such as phenol novolac type epoxy resin, cresol novolak type epoxy resin, arylalkylene type epoxy resin such as biphenyl type epoxy resin and biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin, anthracene Type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin, full Such as epoxy resins such as polyalkylene-type epoxy resins. One of these can be used alone, or two or more can be used in combination.

  (A) Although content of an epoxy resin is not specifically limited, It is preferable that it is 15 to 80 weight% of the resin composition P whole. More preferably, it is 25 to 50% by weight. In addition, it is preferable to use a liquid epoxy resin such as a liquid bisphenol A type epoxy resin or a bisphenol F type epoxy resin because the impregnation property to the fiber base material can be improved. The content of the liquid epoxy resin is more preferably 3 to 14% by weight of the entire resin composition P. Moreover, when solid bisphenol A type epoxy resin and bisphenol F type epoxy resin are used in combination, adhesion to the conductor can be improved.

  The resin composition P may contain a thermosetting resin other than an epoxy resin such as a melamine resin, a urea resin, or a cyanate ester resin, and it is preferable to use a cyanate ester resin in combination. Although it does not specifically limit as a kind of cyanate resin, For example, bisphenol-type cyanate resin, such as a novolak-type cyanate resin, bisphenol A-type cyanate resin, bisphenol E-type cyanate resin, tetramethylbisphenol F-type cyanate resin, etc. can be mentioned. Among these, phenol novolac type cyanate resin is preferable from the viewpoint of low thermal expansion. Furthermore, other cyanate resins may be used alone or in combination of two or more, and are not particularly limited. The cyanate resin is preferably 8 to 20% by weight of the entire resin composition P.

  The resin composition P preferably contains (B) an inorganic filler. (B) Examples of inorganic fillers include silicates such as talc, calcined clay, unfired clay, mica and glass, oxides such as titanium oxide, alumina, silica and fused silica, calcium carbonate, magnesium carbonate and hydrotalc. Carbonate of sites, hydroxides such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, sulfates or sulfites such as barium sulfate, calcium sulfate, calcium sulfite, zinc borate, barium metaborate, aluminum borate And borate salts such as calcium borate and sodium borate, nitrides such as aluminum nitride, boron nitride, silicon nitride and carbon nitride, titanates such as strontium titanate and barium titanate. One of these can be used alone, or two or more can be used in combination.

  Among these, silica is particularly preferable, and fused silica (particularly spherical fused silica) is preferable in terms of excellent low thermal expansion. The shape is crushed and spherical, but in order to reduce the melt viscosity of the resin composition P in order to ensure the impregnation of the fiber base material, a method of use according to the purpose such as using spherical silica is adopted. The

  (B) Although the average particle diameter of an inorganic filler is not specifically limited, 0.01-3 micrometers is preferable and 0.02-1 micrometer is especially preferable. (B) By making the particle size of an inorganic filler 0.01 micrometer or more, a varnish can be made low viscosity and the fiber base material can be made to impregnate the resin composition P favorably. Moreover, sedimentation etc. of (B) inorganic filler can be suppressed in varnish by setting it as 3.0 micrometers or less. This average particle diameter can be measured by, for example, a particle size distribution meter (manufactured by Shimadzu Corporation, product name: laser diffraction particle size distribution measuring device SALD series).

  Further, (B) the inorganic filler is not particularly limited, but an inorganic filler having a monodispersed average particle diameter can also be used, and an inorganic filler having a polydispersed average particle diameter can be used. Furthermore, one type or two or more types of inorganic fillers having an average particle size of monodisperse and / or polydisperse can be used in combination.

  Furthermore, spherical silica (especially spherical fused silica) having an average particle size of 3.0 μm or less is preferable, and spherical fused silica having an average particle size of 0.02 to 1 μm is particularly preferable. Thereby, the filling property of (B) inorganic filler can be improved.

  (B) Content of an inorganic filler is although it does not specifically limit, 2-70 weight% of the whole resin composition P is preferable, and 5-60 weight% is especially preferable. When the content is within the above range, particularly low thermal expansion and low water absorption can be achieved. If necessary, the resin layers 3 and 4 can change the content of the (B) inorganic filler to achieve both adhesion to the conductor and low thermal expansion.

  The resin composition P used for the prepreg 1 is not particularly limited, but (C) a coupling agent is preferably used. (C) Coupling agent improves (A) epoxy resin and (B) inorganic filler to fiber substrate by improving the wettability of the interface between (A) epoxy resin and (B) inorganic filler. The material can be fixed uniformly, and the heat resistance, particularly the solder heat resistance after moisture absorption can be improved.

  (C) Any coupling agent can be used as long as it is usually used. Specifically, an epoxy silane coupling agent, a cationic silane coupling agent, an amino silane coupling agent, a titanate coupling agent, and a silicone oil type. It is preferable to use one or more coupling agents selected from coupling agents. Thereby, the wettability with the interface of (B) inorganic filler can be made high, and thereby heat resistance can be improved more.

  (C) The amount of coupling agent added is not particularly limited because it depends on the specific surface area of (B) inorganic filler, but is preferably 0.05 to 3% by weight with respect to 100 parts by weight of (B) inorganic filler. In particular, 0.1 to 2% by weight is preferable. By setting the content to 0.05% by weight or more, (B) the inorganic filler can be sufficiently covered, and the heat resistance can be improved. By setting the content to 3% by weight or less, the reaction proceeds satisfactorily and a decrease in bending strength or the like can be prevented.

  The resin composition P can further use (D) a phenolic curing agent. As the phenolic curing agent, known or commonly used phenolic novolac resins, alkylphenol novolac resins, bisphenol A novolac resins, dicyclopentadiene type phenol resins, zyloc type phenol resins, terpene modified phenol resins, polyvinylphenols, etc. Can be used in combination.

  (D) As for the compounding quantity of a phenol hardening | curing agent, it is preferable that the equivalent ratio (phenolic hydroxyl group equivalent / epoxy group equivalent) with (A) epoxy resin is 0.1-1.0. As a result, there remains no unreacted phenol curing agent, and the moisture absorption heat resistance is improved. When the resin composition P uses an epoxy resin and a cyanate resin in combination, the range of 0.2 to 0.5 is particularly preferable. This is because the phenol resin not only acts as a curing agent but also promotes curing of the cyanate group and the epoxy group.

  In the resin composition P, (E) a curing accelerator may be used as necessary. (E) A well-known thing can be used as a hardening accelerator. For example, organic metal salts such as zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), trisacetylacetonate cobalt (III), triethylamine, tributylamine, diazabicyclo [2,2 , 2] tertiary amines such as octane, 2-phenyl-4-methylimidazole, 2-ethyl-4-ethylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxyimidazole Imidazoles such as 2-phenyl-4,5-dihydroxyimidazole, phenolic compounds such as phenol, bisphenol A, and nonylphenol, organic acids such as acetic acid, benzoic acid, salicylic acid, paratoluenesulfonic acid, and the like, or a mixture thereof. . As the curing accelerator, one kind including these derivatives can be used alone, or two or more kinds including these derivatives can be used in combination.

  (E) Although content of a hardening accelerator is not specifically limited, 0.05-5 weight% of the resin composition P whole is preferable, and 0.2-2 weight% is especially preferable. By setting the content to 0.05% by weight or more, curing can be sufficiently promoted, and by setting the content to 5% by weight or less, it is possible to prevent a decrease in storage stability of the prepreg 1.

  The resin composition P is a phenoxy resin, polyimide resin, polyamideimide resin, polyamide resin, polyphenylene oxide resin, polyethersulfone resin, polyester resin, polyethylene resin, thermoplastic resin such as polystyrene resin, styrene-butadiene copolymer, styrene. -Thermoplastic elastomers such as polystyrene-based thermoplastic elastomers such as isoprene copolymers, polyolefin-based thermoplastic elastomers, polyamide-based elastomers, and polyester-based elastomers, and diene-based materials such as polybutadiene, epoxy-modified polybutadiene, acrylic-modified polybutadiene, and methacryl-modified polybutadiene An elastomer may be used in combination. Moreover, to this resin composition P, if necessary, addition of the above components such as pigments, dyes, antifoaming agents, leveling agents, ultraviolet absorbers, foaming agents, antioxidants, flame retardants, ion scavengers, etc. A thing may be added.

  The fiber substrate 2 impregnated with the resin composition P is not particularly limited, but glass fiber substrates (glass cloth) such as glass woven fabric and glass nonwoven fabric, polyamide resin fibers, aromatic polyamide resin fibers, wholly aromatic polyamide resins. Consists of woven or non-woven fabrics mainly composed of polyamide resin fibers such as fibers, polyester resin fibers, aromatic polyester resin fibers, polyester resin fibers such as wholly aromatic polyester resin fibers, polyimide resin fibers, fluororesin fibers, etc. Organic fiber base materials such as paper base materials mainly composed of synthetic fiber base materials, craft paper, cotton linter paper, mixed paper of linter and kraft pulp, and the like. Among these, glass cloth is preferable. Thereby, a prepreg having low water absorption, high strength, and low thermal expansion can be obtained.

  Examples of the glass constituting the glass cloth include E glass, C glass, A glass, S glass, D glass, NE glass, T glass, and H glass. Among these, E glass or T glass is preferable. Thereby, the high elasticity of a pull prepreg can be achieved and the thermal expansion coefficient of a prepreg can be made small.

  The method of impregnating the fiber base material 2 with the resin composition P includes, for example, a method of preparing the resin varnish V using the resin composition P, immersing the fiber base material 2 in the resin varnish V, and a method of applying with various coaters And a method of spraying by spraying. Among these, the method of immersing the fiber base material 2 in the resin varnish V is preferable. Thereby, the impregnation property of the resin composition P with respect to the fiber base material 2 can be improved. In addition, when the fiber base material 2 is immersed in the resin varnish V, a normal impregnation coating equipment can be used.

  The solvent used in the resin varnish V desirably has good solubility in the resin component in the resin composition P, but a poor solvent may be used within a range that does not adversely affect the resin varnish V. Examples of the solvent exhibiting good solubility include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclopentanone, tetrahydrofuran, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, ethylene glycol, cellosolve, and carbitol.

  The solid content of the resin varnish V is not particularly limited, but the solid content of the resin composition P is preferably 20 to 80% by weight, particularly preferably 5 to 65% by weight. Thereby, the impregnation property to the fiber base material of the resin varnish V can further be improved. Although the predetermined temperature which makes the fiber base material 2 impregnate the resin composition P is not specifically limited, For example, the prepreg 1 can be obtained by drying at 90-220 degreeC. The thickness of the prepreg 1 is preferably 20 to 100 μm.

  As shown in FIG. 1, the prepreg 1 may have a relatively thick resin layer 3 and a relatively thin resin layer 4 with the fiber substrate 2 as the center, and the fiber substrate 2 as the center. You may have the resin layer which consists of substantially the same thickness. In other words, in the prepreg 1, the center 5 in the thickness direction of the fiber base material may be shifted from the center 6 in the thickness direction of the prepreg. The thickness of the resin layers 3 and 4 is the first surface of the prepreg 1 from the thickness center 5 of the fiber substrate in the sectional view of the prepreg 1 shown in FIG. It is obtained by the distance T1 to S1 and the distance T2 to the second surface S2 of the prepreg 1, where T1 is the thickness of the thick resin layer 3 and T2 is the thickness of the thin resin layer 4. As shown in FIG. 1, the second surface S2 is a surface opposite to the first surface S1. In the prepreg 1, when T1 ≧ T2, T1 / T2 is preferably 1 or more and 5 or less, and more preferably 2 or more and 4 or less.

  The prepreg 1 can be evaluated by measuring the resin flow measured by heating and pressurizing for 5 minutes under the conditions of 171 ± 3 ° C. and 1380 ± 70 kPa in accordance with IPC-TM-650 Method 2.3.17. it can.

  When the resin flow of the prepreg 1 is 15% by weight or more, a prepreg excellent in embedding of a wiring circuit can be obtained. Moreover, if this resin flow is 50 weight% or less, when the prepreg is laminated and pressed, the outflow of the resin composition P can be suppressed. The upper limit is preferably 40% by weight or less, and more preferably 35% by weight or less. By carrying out like this, the thickness uniformity of the laminated board obtained by building up the prepreg 1 can be improved.

  The resin flow can be increased by reducing the average molecular weight of a thermosetting resin such as an epoxy resin contained in the resin composition P used in the prepreg 1. Moreover, a resin flow can be made small by increasing the content of the inorganic filler contained in the resin composition P used for the prepreg 1.

  The prepreg 1 may be a laminate of a plurality of sheets via a metal foil or film. Metal foils include, for example, copper and copper alloys, aluminum and aluminum alloys, silver and silver alloys, gold and gold alloys, zinc and zinc alloys, nickel and nickel alloys, tin and tin alloys, iron and iron Examples thereof include metal foils such as alloy alloys. Of these, copper foil is preferred.

  After laminating a plurality of sheets via a metal foil or film, heating and pressurization may be performed. Although the temperature to heat is not specifically limited, 120-230 degreeC is preferable and especially 150-210 degreeC is preferable. Moreover, the pressure to pressurize is not particularly limited, but is preferably 1 to 5 MPa, and particularly preferably 2 to 4 MPa. By using such a prepreg 1, it is possible to obtain a laminate having excellent dielectric characteristics, mechanical and electrical connection reliability at high temperature and high humidity.

  The prepreg 1 may be wound and laminated in a roll shape. At this time, a support base material may be provided on one side or both sides, and the support base material may be wound and laminated. Examples of the method of winding and laminating the prepreg 1 in a roll shape include the following.

After impregnating the fiber base material 2 with the resin composition P, it is transported to the roll type laminating apparatus together with the supporting base material, and the supporting base material is continuously pressed and heated on the prepreg 1 with a metal roll or an elastic material roll. Laminate by. Then, the prepreg 1 can be wound and laminated | stacked in roll shape by winding up in roll shape.
Moreover, the sheet-like fiber base material 2 wound up in a roll shape is continuously conveyed by a roll, and impregnation and drying are performed on the resin varnish V to produce a prepreg 1 wound and laminated in a roll shape. Also good.

  As the support substrate, a plastic film can be used. For example, polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate (PC), acrylic resin (PMMA), cyclic polyolefin, triacetyl cellulose ( TAC), polyether sulfide (PES), polyether ketone, polyimide and the like. Among these, a PET film and a PEN film are preferable, and a PET film is particularly preferable. The support substrate may be subjected to mat treatment or corona treatment on the laminated surface of the resin layers 3 and 4. In order to peel the supporting substrate after the prepreg 1 is thermally cured, a release layer may be provided on the surface in contact with the prepreg 1.

  Moreover, when providing a support base material in one side, you may provide a protective material in the other surface. In this case, it is conveyed to a roll type laminating apparatus so that the supporting surface is in contact with the second surface S2 and the protective material is in contact with the first surface S1, and a metal roll or an elastic material roll is formed from both the supporting substrate and the protective material. Can be laminated by pressurizing and heating. As the protective material, for example, polyolefins such as polyethylene, polypropylene, and polyvinyl chloride, polyesters such as PET and PEN, and plastic films such as PC and polyimide can be used. The thickness of the protective material is preferably in the range of 5 to 30 μm.

[Laminated board]
Next, a laminate using the prepreg 1 will be described. The laminate includes a core layer having a circuit formation surface on one side or both sides, and a build-up layer laminated on the circuit formation surface of the core layer. The build-up layer is formed by curing the prepreg 1 described above.

  The core layer is a sheet-like thing having a circuit forming surface in which one side or both sides of a substrate such as a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, and a thermosetting polyphenylene ether substrate are patterned. . The core layer further includes an inner layer circuit board of an intermediate product on which a buildup layer and a wiring circuit are to be formed.

  The manufacturing method of the core layer is not particularly limited. For example, a core layer having a metal foil on both sides is used, a predetermined place is opened with a drill machine, and the both sides of the core layer are made conductive by electroless plating. . Then, the inner layer circuit is formed by etching the metal foil. Note that the inner layer circuit portion can be suitably used after being subjected to roughening processing such as blackening processing. The opening can be appropriately filled with a conductor paste or a resin paste.

  This laminated board can be manufactured as follows. First, a prepreg 1 wound in a roll shape is prepared and conveyed to a laminator together with the sheet-shaped core layer. The laminator includes a pair of opposing metal plates and a plate-like elastic body such as a heat insulating rubber, and is heated and pressurized by the metal plate with the core layer and the prepreg sandwiched through the elastic body, Lamination (lamination process). As the laminator, it is preferable to use a laminator (vacuum laminator) that is heated and pressurized under vacuum. As the metal plate, for example, a SUS end plate can be used. Heating and pressurization are preferably performed in the range of 80 to 140 ° C. and 0.4 to 1.5 MPa.

  The above laminator step can be performed using a commercially available vacuum laminator. For example, a vacuum pressurizing laminator provided in Nichigo-Morton CPV300 or an equivalent thereof can be used.

  After the laminator process, the resin layers 3 and 4 of the prepreg 1 are softened and follow the inner layer wiring of the core layer to be deformed into irregularities. Therefore, the laminated adhesive sheet is smoothed by hot pressing the laminated buildup layer and the core layer with a pair of opposing metal plates (smoothing step). The smoothing step is performed by heating and pressurizing the adhesive sheet with a metal plate such as a heated SUS mirror plate under atmospheric pressure. The smoothing press is preferably performed in the range of 100 to 170 ° C. and 0.4 to 1.5 MPa.

  Such a smoothing step can be performed using a commercially available hot press apparatus. For example, a hot press apparatus provided in a CPV300 manufactured by Nichigo-Morton Co., Ltd. or an equivalent thereof may be used. it can.

  Thereafter, the resin layers 3 and 4 of the prepreg 1 are cured by heating. Although the temperature to harden | cure is not specifically limited, For example, it can be made to harden | cure in the range of 100-250 degreeC, Preferably it can be made to harden | cure at 150-200 degreeC. The curing time can be about 30 to 75 minutes.

  Next, the cured resin layer is irradiated with a laser to form an opening, and the resin residue after the laser irradiation is preferably removed with an oxidizing agent such as permanganate or dichromate. . Further, the surface of the smooth resin layer can be simultaneously roughened, and the adhesion of the conductive wiring circuit formed by subsequent metal plating can be improved. The resin layer can be uniformly provided with fine irregularities in the roughening treatment. Moreover, since the smoothness of the resin layer surface is high, a fine wiring circuit can be formed with high accuracy. Thereafter, a solder resist is formed on the outermost layer, the connection electrode part is exposed so that a semiconductor element can be mounted by exposure and development, nickel gold plating is performed, and the laminate is cut to a predetermined size. .

  When the resin amount of the prepreg 1 is different between the first surface S1 side and the second surface S2 side, that is, when T1> T2 in FIG. 1, the first surface S1 with a large amount of resin is the circuit forming surface. It is preferable to be laminated. By carrying out like this, resin can fully be supplied to the space | gap which has arisen between the wiring circuit and the prepreg, and heat resistance can be ensured.

[Semiconductor device]
Next, a semiconductor device will be described.
This semiconductor device can be manufactured by mounting a semiconductor element on the laminated wiring board. The mounting method and the sealing method of the semiconductor element are not particularly limited. For example, it can be manufactured by the following method.

  First, using a flip chip bonder or the like, the connection electrode portion on the laminated wiring board and the solder bump of the semiconductor element are aligned. Next, the solder bump is heated to the melting point or higher by using an IR reflow device, a hot plate, or other heating device, and the multilayer printed wiring board and the solder bump are connected by fusion bonding. Finally, a liquid sealing resin is filled between the laminated wiring board and the semiconductor element and cured to obtain a semiconductor device.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

The prepreg shown in FIG. 1 was produced.
The raw materials used in Examples and Comparative Examples are as follows.
Inorganic filler: spherical silica (manufactured by Admatechs, SO-25R, average particle size 0.5 μm)
Epoxy resin: biphenyl aralkyl type novolac epoxy resin (NC-3000 manufactured by Nippon Kayaku Co., Ltd.)
Epoxy resin: dicyclopentadiene type novolac epoxy resin (manufactured by DIC, HP-7200L, HP-7200)
Cyanate resin: Novolac type cyanate resin (Primase PT-30 manufactured by LONZA)
Epoxy resin: Bisphenol A type liquid epoxy resin (Mitsubishi Chemical Corporation, jER-828)
Epoxy resin: Bisphenol F type liquid epoxy resin (Mitsubishi Chemical Corporation, jER-807)
Phenol curing agent: novolak type phenol resin (manufactured by DIC, TD-2090-60M, 60% (w / v) methyl ethyl ketone solution)
Phenoxy resin: manufactured by Mitsubishi Chemical Corporation, YX6954BH30, 30% (w / v) methyl ethyl ketone / anone solution)
Polyvinyl acetal resin: KS-10 (hydroxyl group 25 mol%) manufactured by Sekisui Chemical Co., Ltd.
Curing catalyst: 2-ethyl-4-methylimidazole (2E4MZ manufactured by Shikoku Chemicals)
Coupling agent: N-phenyl-3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-573)

Example 1
(1) Preparation of varnish 30 parts by weight of dicyclopentadiene type epoxy resin (manufactured by DIC, HP-7200) as epoxy resin, 3 parts by weight of bisphenol F type liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER807), phenol as cyanate resin 14 parts by weight of novolak-type cyanate resin (LONZA, Primaset PT-30), 3 parts by weight of YX6954BH30 manufactured by Mitsubishi Chemical Corporation as the phenoxy resin, and 0.2 parts by weight of imidazole (manufactured by Shikoku Kasei Co., Ltd., 2E4MZ) as the curing catalyst The portion was stirred for 60 minutes with a mixed solvent of methyl ethyl ketone and cyclohexanone to dissolve. Furthermore, 0.1 part by weight of N-phenyl-3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-573) as a coupling agent and spherical silica (SO25R manufactured by Admatechs Co., Ltd., average particle size 0) as an inorganic filler. 0.5 μm) 49.7 parts by weight were added and stirred for 10 minutes with a high-speed stirrer to prepare a resin varnish with a solid content of 65%.
(2) Production of resin sheet The varnish was coated on one side of a PET (polyethylene terephthalate) film having a thickness of 36 μm using a comma coater device, which was dried for 3 minutes with a 160 ° C. drying device, with a substrate. A resin sheet was formed.
Two types of resin sheets having a resin thickness of 22 μm (resin sheet 1) and 13 μm (resin sheet 2) were produced.
(3) Preparation of prepreg A glass woven fabric (manufactured by Unitika Ltd., cross type # 1017, width 530 mm, thickness 15 μm, basis weight 12 g / m ² ) was used as a fiber substrate, and the prepreg was prepared by a vacuum laminator and a hot air dryer. Manufactured.
Specifically, the resin sheet 1 and the resin sheet 2 are overlapped on both sides of the glass woven fabric so that they are positioned at the center in the width direction of the glass woven fabric, respectively, and under reduced pressure conditions of 0.1 MPa (750 Torr), It joined using the 80 degreeC laminate roll.
Here, in the inner region of the width direction dimension of the glass woven fabric, the resin layers of the resin sheet 1 and the resin sheet 2 are respectively bonded to both sides of the fiber cloth, and in the outer region of the width direction dimension of the glass woven fabric. The resin layers of the resin sheet 1 and the resin sheet 2 were joined together.
Next, the joined material is heated for 2 minutes through a horizontal conveying type hot air drying apparatus set at 120 ° C. without applying pressure, and has a thickness of 40 μm (T1: 17 μm, fiber base material). : 15 μm, T2: 8 μm).

Example 2
(1) Preparation of varnish Prepared in the same manner as in Example 1.
(2) Production of Resin Sheet A resin sheet was produced in the same manner as in Example 1 except that the resin thickness on the substrate was changed to 20.5 μm (resin sheet 1) and 13.5 μm (resin sheet 2).
(3) Preparation of prepreg A glass woven fabric was prepared in the same manner as in Example 1 except that the woven cloth was changed to a cloth type # 1015 (width 530 mm, thickness 17 μm, basis weight 15 g / m ² ).

Example 3
A varnish, a resin sheet, and a prepreg were prepared in the same manner as in Example 1 except that the resin composition was changed to the resin composition shown in Table 1.

Example 4
(1) Preparation of varnish It was prepared in the same manner as in Example 1 except that the resin composition was changed to the resin composition shown in Table 1.
(2) Production of Resin Sheet A resin sheet was produced in the same manner as in Example 1 except that the resin thickness on the substrate was changed to 16 μm for both the resin sheets 1 and 2.
(3) Production of prepreg A glass woven fabric was produced in the same manner as in Example 1 except that the woven cloth was changed to cross type # 1027 (width 530 mm, thickness 20 μm, basis weight 20 g / m ² ).

Comparative Examples 1 and 2
A varnish, a resin sheet, and a prepreg were prepared in the same manner as in Example 1 except that the resin composition was changed to the resin composition shown in Table 1.

[Resin flow (% by weight)]
It measured based on IPC-TM-650 Method 2.3.17 using the prepreg of Examples 1-5 or Comparative Examples 1 and 2. That is, as shown in FIG. 2, the prepregs of Examples 1 to 5 or Comparative Examples 1 and 2 were cut into a square of 102 mm × 102 mm, four of them were stacked, and the weight (W ₀ (g)) was measured. did. A release film (product name: Sepanium 20M2C-S, manufacturer: Sun Aluminum Industry Co., Ltd., size: 200 mm × 240 mm) was pasted on both sides of the outermost layer of the prepreg (FIG. 2A). ). Thereafter, a prepreg was placed between the two SUS plates, heated to 171 ° C. and 1.38 MPa, and hot-plate pressed for 5 minutes (FIG. 2B). Next, the release film is peeled off, and the prepreg is cut out into a columnar shape having a diameter of 81 mm so that the stacking direction of the prepreg is in the height direction (FIG. 2C), and the weight of the obtained columnar prepreg (W ₂ ( g)) was measured. The resin flow was determined from equation (1). The results are shown in Table 1. In the formula (1),% is% by weight.

  It was visually confirmed that the resin protrusion length of the prepregs of Examples 1 to 4 was at most 20 mm.

[Evaluation]
1. Manufacture of Laminate A laminate was produced from the prepreg with PET base material of Examples 1 to 4 and Comparative Examples 1 and 2 using a 2-stage buildup laminator CVP300 manufactured by Nichigo-Morton. Specifically, using ELC-4785GS-B (Sumitomo Bakelite Co., Ltd., copper foil 12 μm) with a thickness of 200 μm, a predetermined place is opened with a drill machine, and conduction is achieved by electroless plating. Was etched to prepare a core layer having a circuit formation surface. Also, the prepregs of Examples 1 to 4 and Comparative Examples 1 and 2 were cut into single sheets, set on the CVP300, temporarily attached to the core layer, and vacuumed at 120 ° C., 0.7 MPa for 1 minute in a vacuum laminator. Lamination was performed, followed by smoothing by hot pressing at 160 ° C., 0.55 MPa for 2 minutes. Then, it hardened | cured at 170 degreeC.

2. Embeddability in circuit The cross section of the laminate was observed with a scanning electron microscope (SEM) to confirm whether resin was embedded between the circuits. Those in which resin was embedded between the circuits were accepted, and voids remained between the circuits, and those that were insufficiently embedded were rejected. The results are shown in Table 1. In Table 1, the acceptance is indicated by ○, and the rejection is indicated by ×.

3. Thickness variation The cross section of the laminate was observed with a scanning electron microscope (SEM), and the difference in thickness between the adjacent portion with and without the copper wiring was measured.
The difference in thickness was measured at n = 10, and an average of less than 0.8 μm was accepted, and an average of 0.8 μm or more was rejected. The results are shown in Table 1. In Table 1, the acceptance is indicated by ○, and the rejection is indicated by ×.

DESCRIPTION OF SYMBOLS 1 Prepreg 2 Fiber base material 3 Resin layer 4 Resin layer 5 Center of thickness direction of fiber base 6 Center of thickness direction of prepreg S1 First surface S2 Second surface

According to the present invention,
A fiber base and a resin layer provided on both sides of the fiber base and containing a thermosetting resin containing an epoxy resin (excluding polyphenylene ether) ;
According to IPC-TM-650 Method 2.3.17, the resin flow measured by heating and pressing for 5 minutes under the conditions of 171 ± 3 ° C. and 1380 ± 70 kPa is 15% by weight or more and 50% by weight or less. A build-up prepreg is provided.

According to the present invention,
A glass woven fabric, and a resin layer provided on both surfaces of the glass woven fabric , containing a thermosetting resin containing an epoxy resin (excluding polyphenylene ether and interpenetrating polymer network );
Conforming to IPC-TM-650 Method 2.3.17, 171 ± 3 ℃, 1380 resin flow was measured by heating and pressing 5 minutes at a ± 70 kPa is state, and are 15 wt% to 50 wt% or less A build-up prepreg wound and laminated in a roll shape is provided.

Claims (11)

A fiber base and a resin layer provided on both sides of the fiber base;
According to IPC-TM-650 Method 2.3.17, the resin flow measured by heating and pressing for 5 minutes under the conditions of 171 ± 3 ° C. and 1380 ± 70 kPa is 15% by weight or more and 50% by weight or less. Pre-preg for build-up.   The prepreg for buildup according to claim 1, wherein the prepreg is wound and laminated in a roll shape.   The prepreg for buildup according to claim 2, wherein a support base material is provided on one side or both sides, and the laminate is wound and laminated with the support base material interposed.   The prepreg for buildup according to any one of claims 1 to 3, comprising a relatively thick resin layer and a relatively thin resin layer centering on the fiber base material.   The prepreg for buildup according to any one of claims 1 to 4, wherein a metal foil is provided on one side or both sides. A core layer having a circuit forming surface on one or both sides;
A buildup layer laminated on the circuit forming surface of the core layer;
With
The said buildup layer is a laminated board formed by hardening | curing the prepreg for buildup of any one of Claims 1 thru | or 5. The build-up prepreg has a relatively thick resin layer and a relatively thin resin layer around a fiber base material,
The laminated board according to claim 6, wherein the thick resin layer is laminated on the circuit forming surface. The laminate according to claim 6 or 7,
A semiconductor element mounted on the laminate,
A semiconductor device comprising: A laminating step of laminating a prepreg for buildup on the circuit forming surface of the core layer having a circuit forming surface on one side or both sides under heat and pressure;
A smoothing step of smoothing the surface of the laminated prepreg for buildup to obtain a laminate;
A method of manufacturing a laminated board that continuously performs
In the laminating step, heating and pressurizing the core layer and the prepreg for buildup sandwiched between a pair of opposing metal plates,
The manufacturing method of a laminated board using the prepreg for buildup of any one of Claims 1 thru | or 5 as said prepreg for buildup. The prepreg for buildup is wound and laminated in a roll shape,
The manufacturing method of the laminated board of Claim 9 which conveys the sheet-like core layer while conveying the roll-up laminated buildup prepreg, and performing the said lamination process and the said smoothing process continuously. .   The manufacturing method of the laminated board of Claim 10 which heats and pressurizes in the said smoothing process in the state which pinched | interposed the said core layer and the said prepreg for buildup with a pair of opposing plate-shaped elastic body.

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