JP5448414B2 - Resin composition, prepreg, laminate, multilayer printed wiring board, and semiconductor device - Google Patents

Description

The present invention relates to a resin composition, a prepreg, a laminated board, a multilayer printed wiring board, and a semiconductor device.

  In recent years, with the demand for higher functionality of electronic devices, printed wiring boards compatible with high-density mounting have been required to be smaller and higher in density, the width of the conductor circuit formed on the printed wiring board, or the conductor circuit The gap width tends to become even narrower. For example, an inner layer circuit board used in a multilayer printed wiring board has a conductor circuit width and a conductor circuit width (L / S) narrowed from the conventional 100 μm / 100 μm to 50 μm / 50 μm, and further 20 μm / 20 μm. Because of this tendency, practical application of L / S of 15 μm / 15 μm is being studied, particularly in the outer layer circuit of a multilayer printed wiring board. When L / S becomes narrower, the insulating layer used for the multilayer printed wiring board is required to have higher reliability than the conventional one. Specifically, further reduction in the coefficient of thermal expansion of an insulating layer formed from a resin composition such as an epoxy resin composition is required.

  As a technique for reducing the thermal expansion of a multilayer printed wiring board, a method of highly filling an inorganic filler has been proposed (for example, described in Patent Document 1). However, when a large amount of the inorganic filler is filled in the resin composition, the fluidity of the resin composition is lowered, and there is a problem that the moldability is deteriorated when the multilayer printed wiring board is manufactured. For this reason, in order to prevent the fluidity of the resin composition from being lowered, a method of highly filling spherical silica has also been proposed, but since silica has high hardness, when only silica is highly filled, the wear of the drill is severe and the workability is high. There was a problem of lowering.

  Furthermore, with the recent increase in awareness of environmental problems, multilayer printed wiring boards are required not to contain halogen-based flame retardants or phosphorus-based flame retardants. Gibbsite, which is a trihydrate of aluminum hydroxide, is generally used as a flame retardant to impart flame retardancy to a multilayer printed wiring board (for example, described in Patent Document 2). However, since gibbsite has a crystal water release temperature lower than the melting point of lead-free solder, there may be a problem in heat resistance during solder mounting. Therefore, it has been proposed to improve the heat resistance of the multilayer printed wiring board by using boehmite, which is a monohydrate of aluminum hydroxide having a higher release temperature.

  However, since conventional boehmite is a monohydrate, there has been a problem that a flame retardant effect equivalent to that of gibbsite cannot be obtained.

JP 2002-28501 A JP 2001-316499 A

    When the present invention is used for an insulating layer of a multilayer printed wiring board, a highly reliable multilayer printed wiring board having heat resistance, low thermal expansion, flame retardancy, drilling workability and formability can be produced. A resin composition, a prepreg, a laminate, a multilayer printed wiring board, and a semiconductor device are provided.

Such an object is achieved by the present invention described in the following items (1) to (11).
(1) A resin composition characterized by comprising substantially cubic boehmite as an essential component.
(2) The resin composition according to item (1), wherein the BET specific surface area of the substantially cubic boehmite is 1 m ² / g or more and 20 m ² / g or less.
(3) The resin composition as described in (1) or (2), wherein the average particle size of the substantially cubic boehmite is 0.5 μm or more and 10 μm or less.
(4) The resin composition according to any one of (1) to (3), wherein the content of the substantially cubic boehmite is 10 wt% or more and 70 wt% or less of the entire resin composition.
(5) The resin composition according to any one of (1) to (4), wherein the resin composition contains silica.
(6) The resin composition according to (5), wherein the silica has an average particle size of 0.1 μm or more and 2 μm or less.
(7) The resin composition according to any one of (1) to (6) is a resin composition containing a thermosetting resin.
(8) A prepreg obtained by impregnating a fiber base material with the resin composition according to any one of (1) to (7).
(9) A laminate obtained by molding one or more prepregs according to item (8).
(10) A multilayer printed wiring board using the prepreg according to the item (8) and / or the laminate according to the item (9).
(11) A semiconductor device comprising a semiconductor element mounted on the multilayer printed wiring board according to item (10).

    The resin composition of the present invention is excellent in heat resistance, low thermal expansion, flame retardancy, drill workability, and moldability when used in an insulating layer of a multilayer printed wiring board.

    Hereinafter, the resin composition, prepreg, laminate and semiconductor device of the present invention will be described in detail.

  First, the resin composition of the present invention will be described.

The resin composition of the present invention is characterized by containing substantially cubic boehmite as an essential component.
The substantially cubic shape means a cubic shape and approximate shapes thereof. The substantially cubic shape corresponds to, for example, a “dice-like” shape in which the length of each side is substantially equal. As a result, the resin composition can be highly filled, and the dimensional stability of the laminate is improved.

The BET specific surface area of the substantially cubic boehmite used in the resin composition of the present invention is preferably 1 m ² / g or more and 20 m ² / g.
Here, the BET surface area refers to the surface area of a sample that can be obtained from the amount of gas such as nitrogen adsorbed on the sample surface, and can be measured using, for example, Flowsorb III2305 manufactured by Micromeritics.
Substantially BET specific surface area of the cubic boehmite, more preferably, is of 2.0 to 10.0 m ² / g, most preferably of 3.0~7.0m ² / g. When the BET specific surface area is less than the lower limit, the resin surface roughness when the surface of a prepreg made of a resin composition in a B-staged state or a cured state is roughened by chemical and / or physical treatment is large. Thus, when used in a multilayer printed wiring board, the insulation reliability may be reduced. Moreover, since the viscosity of a resin varnish will become high too much when exceeding an upper limit, it will become difficult to carry out high filling of an inorganic filler. Further, when used in a prepreg, the fluidity is lowered, so that the moldability during the production of the laminated board is lowered, and the embedding property of the inner layer circuit may be lowered in the production of the multilayer printed wiring board.

The average particle size of the substantially cubic boehmite used in the resin composition of the present invention is preferably 0.5 μm or more and 10 μm or less. More preferably, it is 1.0 μm or more and 7.0 μm or less, and most preferably 1.5 μm or more and 3.0 μm or less. An example of such a substantially cubic boehmite is C-20 manufactured by Daimei Chemical Industry. When the average particle size of boehmite is less than the lower limit, the viscosity of the varnish made of the resin composition becomes high, so that it is difficult to impregnate the fiber base material, and it becomes difficult to produce a prepreg. Moreover, when the said upper limit is exceeded, boehmite will settle easily in a varnish, and productivity will fall.
The average particle diameter can be measured by, for example, a particle size distribution meter (manufactured by HORIBA, LA-500).

    The blending amount of the substantially cubic boehmite is preferably 30% by weight or more and 60% by weight or less.

The resin composition of this invention can use together inorganic fillers other than a substantially cubic boehmite. Examples of inorganic fillers other than boehmite include metal hydroxides such as aluminum hydroxide and magnesium hydroxide, talc, fired talc, fired clay, unfired clay, mica, silicates such as glass, titanium oxide, alumina, Oxides such as silica and fused silica, carbonates such as calcium carbonate, magnesium carbonate and hydrotalcite, sulfates or sulfites such as barium sulfate, calcium sulfate and calcium sulfite, zinc borate, barium metaborate and 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. Of these, silica is preferable. Particularly preferred is spherical silica.

The average particle diameter of the inorganic filler other than the substantially cubic boehmite is preferably 0.1 μm or more and 2 μm or less. More preferably, it is 0.3 μm or more and 1.0 μm or less. Thereby, fluidity and low thermal expansion can be effectively imparted without impairing heat resistance and flame retardancy.
If it is less than the lower limit, at the time of producing the prepreg, the viscosity of the resin varnish made of the resin composition becomes high, so that high filling is difficult, and it may be difficult to reduce the thermal expansion of the prepreg. Moreover, when the said upper limit is exceeded, the workability at the time of drilling a prepreg may fall.

The blending amount of the inorganic filler is preferably 50% by weight or more and 80% by weight or less of the entire resin composition. More preferably, it is 55 to 75 weight%, Most preferably, it is 60 to 70 weight%. If the blending amount of the inorganic filler is less than the lower limit value, sufficient low expansion may not be obtained, and if the upper limit value is exceeded, the fluidity is lowered, and the moldability and embeddability cannot be obtained, resulting in voids. May occur and heat resistance may be reduced.

  The resin component contained in the resin composition of the present invention is not particularly limited. For example, phenoxy resin, polyimide resin, polyamideimide resin, polyphenylene oxide resin, polyethersulfone resin, polyester resin, polyethylene resin, polystyrene resin, etc. Thermoplastic resins, styrene-butadiene copolymers, polystyrene-type thermoplastic elastomers such as styrene-isoprene copolymers, polyolefin-type thermoplastic elastomers, polyamide-type elastomers, polyester-type elastomers, etc., polybutadiene, epoxy-modified polybutadiene , Diene elastomers such as acrylic modified polybutadiene and methacryl modified polybutadiene, epoxy resin, phenol resin, cyanate resin, benzoxazine resin, polyester Include thermosetting resin such as an imide resin. These may be used alone or in combination. The resin composition of the present invention is preferably a resin composition containing a thermosetting resin. Thereby, the heat resistance of the resin composition can be improved.

Examples of the thermosetting resin include a novolak phenol resin such as a phenol novolak resin, a cresol novolak resin, and a bisphenol A type novolak resin, an unmodified resole phenol resin, an oil-modified resole modified with tung oil, linseed oil, walnut oil, and the like. Phenol resin such as phenolic resin, 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 Bisphenol type epoxy resin such as Z type epoxy resin, novolak type epoxy resin such as phenol novolac type epoxy resin, cresol novolac epoxy resin, biphenyl type epoxy Fatty, biphenyl aralkyl type epoxy resin, aryl alkylene 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, fluorene type epoxy resin Such as epoxy resin, urea (urea) resin, melamine resin, etc., resin having triazine ring, unsaturated polyester resin, bismaleimide resin, polyurethane resin, diallyl phthalate resin, silicone resin, resin having benzoxazine ring, cyanate resin, etc. Is mentioned.
One of these can be used alone, or two or more having different weight average molecular weights can be used in combination, or one or two or more of these prepolymers can be used in combination. A phenoxy resin having a structure having a plurality of types can also be used. These may be used alone or in combination.

  Among the thermosetting resins, an epoxy resin (substantially free of halogen atoms) is preferably used. Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, bisphenol M type epoxy resin, bisphenol P type epoxy resin, and bisphenol Z type epoxy resin. Type epoxy resins, phenol novolac type epoxy resins, cresol novolac epoxy resins and other novolak type epoxy resins, biphenyl type epoxy resins, xylylene type epoxy resins, biphenyl aralkyl type epoxy resins and other aryl alkylene type epoxy resins, naphthalene type epoxy resins, anthracene Type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type epoxy resin, adamantane Epoxy resins, fluorene type epoxy resins and the like. As the epoxy resin, one of these can be used alone, or two or more having different weight average molecular weights are used in combination, or one or two or more thereof and a prepolymer thereof are used in combination. You can also.

The resin composition of this invention can use a hardening accelerator as needed.

The curing accelerator is not particularly limited, but for example, tertiary amines such as triethylamine, tributylamine, diazabicyclo [2,2,2] octane, 2-ethyl-4-ethylimidazole, 2-phenyl-4-methyl Imidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')] -Ethyl-s-triazine, 2,4-diamino-6- (2'-undecylimidazolyl) -ethyl-s-triazine, 2,4-diamino-6- [2'-ethyl-4-methylimidazolyl- ( 1 ′)]-ethyl-s-triazine, imidazole compounds such as 1-benzyl-2-phenylimidazole, triphenyl Phosphine compounds such as phosphine.

Although content of the said hardening accelerator is not specifically limited, 0.05-5 weight% of the whole said resin composition is preferable, and 0.2-2 weight% is especially preferable. When the content is less than the lower limit, the effect of promoting curing may not appear, and when the content exceeds the upper limit, the storability of the prepreg may deteriorate.

The resin composition is not particularly limited, but it is preferable to use a coupling agent. The coupling agent improves the wettability of the interface between the thermosetting resin and the inorganic filler, thereby uniformly fixing the thermosetting resin or the like and the inorganic filler to the base material. Can be improved. Especially, the solder heat resistance after moisture absorption can be improved.

  Although it does not specifically limit as said coupling agent, For example, 1 chosen from an epoxy silane coupling agent, a cationic silane coupling agent, an aminosilane coupling agent, a titanate coupling agent, and a silicone oil type coupling agent. It is preferred to use more than one type of coupling agent. Thereby, wettability with the interface of an inorganic filler can be improved, and heat resistance can be improved more.

The addition amount of the coupling agent is not particularly limited because it depends on the specific surface area of the inorganic filler, but is preferably 0.05 to 3% by weight, particularly 0.1 to 2% by weight with respect to the inorganic filler. preferable. If the content is less than the lower limit, the inorganic filler cannot be sufficiently coated, and thus the effect of improving the heat resistance may be reduced. If the content exceeds the upper limit, the reaction is affected, and the bending strength is reduced. There is a case.

In the resin composition of the present invention, additives other than the above components such as pigments, dyes, antifoaming agents, leveling agents, ultraviolet absorbers, foaming agents, antioxidants, flame retardants, ion scavengers, etc. May be added.

  Next, the prepreg will be described.

  The prepreg of the present invention is obtained by impregnating a base material with the resin composition. Thereby, it is possible to obtain a prepreg suitable for manufacturing a printed wiring board excellent in various characteristics such as dielectric characteristics, mechanical and electrical connection reliability under high temperature and high humidity.

Examples of the substrate include glass fiber substrates such as glass woven fabric and glass nonwoven fabric, polyamide resin fibers, aromatic polyamide resin fibers, polyamide resin fibers such as wholly aromatic polyamide resin fibers, polyester resin fibers, and aromatic polyester resins. Synthetic fiber base material, kraft paper, cotton linter paper, linter, etc. composed of woven fabric or non-woven fabric mainly composed of fibers, polyester resin fibers such as wholly aromatic polyester resin fibers, polyimide resin fibers, fluororesin fibers, etc. Examples thereof include organic fiber base materials such as paper base materials mainly containing kraft pulp mixed paper. Among these, a glass fiber base material is preferable. Thereby, the intensity | strength of a prepreg and a water absorption rate can be improved. Moreover, the thermal expansion coefficient of the prepreg can be reduced.

  Examples of the method of impregnating the substrate with the resin composition include, for example, preparing a resin varnish using the resin composition of the present invention, immersing the substrate in the resin varnish, applying with various coaters, and spraying by spraying Methods and the like. Among these, the method of immersing the base material in the resin varnish is preferable. Thereby, the impregnation property of the resin composition with respect to the fiber base material can be improved. In addition, when a base material is immersed in a resin varnish, a normal impregnation coating equipment can be used.

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

  The solid content of the resin varnish is not particularly limited, but the solid content of the resin composition is preferably 40 to 80% by weight, and particularly preferably 50 to 75% by weight. Thereby, the impregnation property to the fiber base material of the resin varnish can further be improved. A prepreg can be obtained by impregnating the fiber base material with the resin composition and drying at a predetermined temperature, for example, 80 to 200 ° C.

  Next, a laminated board is demonstrated.

The laminate of the present invention is formed by molding at least one of the above prepregs. Thereby, the laminated board excellent in the dielectric property and the mechanical and electrical connection reliability in high temperature and high humidity can be obtained.
In the case of a single prepreg, a metal foil or film is stacked on both upper and lower surfaces or one surface. Two or more prepregs can be laminated. When two or more prepregs are laminated, a metal foil or film is laminated on the outermost upper and lower surfaces or one surface of the laminated prepreg. Next, a laminate can be obtained by heating and pressurizing a laminate of a prepreg and a metal foil. Although the temperature to heat is not specifically limited, 120-240 degreeC is preferable and especially 150-230 degreeC is preferable. Moreover, the pressure to pressurize is not particularly limited, but is preferably 2 to 5 MPa, and particularly preferably 2.5 to 4 MPa.

The metal foil is, for example, copper and copper alloy, aluminum and aluminum alloy, silver and silver alloy, gold and gold alloy, zinc and zinc alloy, nickel and nickel alloy, tin and tin alloy, iron And those obtained from iron-based alloys and the like.
Examples of the film include polyethylene, polypropylene, polyethylene terephthalate, polyimide, and fluorine resin.

Next, a multilayer printed wiring board will be described.

  An inner layer circuit board is prepared by preparing a laminated board having copper foil on the upper and lower surfaces, forming a predetermined conductor circuit (inner layer circuit) by etching or the like on both surfaces, and subjecting the conductor circuit to a roughening treatment such as blackening treatment. Is made.

  Next, a commercially available resin sheet or the above-described prepreg is formed on the upper and lower surfaces of the inner layer circuit board, and is heated and pressed.

Specifically, the resin sheet or prepreg and the inner layer circuit board are combined and subjected to vacuum heating and press molding using a vacuum pressurizing laminator apparatus or the like. Thereafter, the insulating layer can be formed on the inner circuit board by heat-curing with a hot air drying device or the like.
Although it does not specifically limit as conditions to heat-press form here, if an example is given, it can implement at the temperature of 60-160 degreeC, and the pressure of 0.2-3 MPa. Moreover, it is although it does not specifically limit as conditions to heat-harden, If an example is given, it can implement in temperature 140-240 degreeC and time 30-120 minutes.

As another method, an insulating layer can be formed on the inner layer circuit board by superposing a resin sheet or a prepreg on the inner layer circuit board and then heating and pressing the same using a flat plate press or the like. .
Although it does not specifically limit as conditions to heat-press form here, If an example is given, it can implement at the temperature of 140-240 degreeC, and the pressure of 1-4 MPa.

  The substrate obtained by the above method can form a new conductive wiring circuit by metal plating after roughening the surface of the insulating layer with an oxidizing agent such as permanganate or dichromate.

  Thereafter, the insulating layer is 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 to 250 degreeC. Preferably it is made to harden | cure at 150 to 200 degreeC.

  Next, an opening is provided in the insulating layer by using a carbonic acid laser device, and an outer layer circuit is formed on the surface of the insulating layer by electrolytic copper plating to achieve conduction between the outer layer circuit and the inner layer circuit. The outer layer circuit is provided with a connection electrode portion for mounting a semiconductor element.

After that, a solder resist layer 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 treatment is performed, and a predetermined size is obtained to obtain a multilayer printed wiring board be able to.

  Next, a semiconductor device will be described.

  The semiconductor device can be manufactured by mounting a semiconductor element on the multilayer printed wiring board manufactured by the above method.

  The mounting method and the sealing method of the semiconductor element are not particularly limited. For example, the semiconductor device and the multilayer printed wiring board are used, and the connection electrode portion and the semiconductor on the multilayer printed wiring board using a flip chip bonder or the like. Align with the solder bump of the element. Thereafter, 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. And a semiconductor device can be obtained by filling and hardening a liquid sealing resin between a multilayer printed wiring board and a semiconductor element.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples.

The raw materials used in Examples and Comparative Examples are as follows.
(1) Inorganic filler A / substantially cubic boehmite A; C60 manufactured by Daimei Chemical Co., Ltd. Average particle size 6.0 μm BET specific surface area 3.0 m ² / g
(2) Inorganic filler B / substantially cubic boehmite B; C20 manufactured by Daimei Chemical Co., Ltd. Average particle size 1.9 μm BET specific surface area 4.0 m ² / g
(3) Inorganic filler C / substantially cubic boehmite C; C06 produced by Daimei Chemical Co., Ltd. Average particle size 0.6 μm BET specific surface area 15 m ² / g
(4) Inorganic filler D / silica; Admatex SO-C2, average particle size 0.5 μm
(5) Inorganic filler E / silica; Admatex SO-C4, average particle size 1.0 μm
(6) Inorganic filler F / silica; SFP-20M manufactured by Denki Kagaku Kogyo Co., Ltd., average particle size 0.3 μm
(7) Inorganic filler G / aluminum hydroxide; BE033 manufactured by Nippon Light Metal Co., Ltd., average particle size 2.2 μm
(8) Inorganic filler H / plate boehmite; BMT average particle diameter of 4.0 μm manufactured by Kawai Lime Industry Co., Ltd.
(9) Inorganic filler I / acicular boehmite; BMI average particle size of 4.0 μm manufactured by Kawai Lime Industry Co., Ltd.
(10) Epoxy resin A / dicyclopentadiene type epoxy resin; “HP7200H” manufactured by DIC
(11) Epoxy resin B / methoxynaphthalene dimethylene type epoxy resin; “HP-4032D” manufactured by DIC
(12) Epoxy resin C / biphenyldimethylene type epoxy resin: “NC-3000” manufactured by Nippon Kayaku Co., Ltd.
(13) Cyanate resin / Novolac type cyanate resin: Lonza Japan Co., Ltd. “Primaset PT-30”
(14) Phenol resin A / triazine novolac resin; "KA-1356" manufactured by DIC
(15) Phenol resin B / triazine novolac resin; “LA-3018” manufactured by DIC
(16) Phenol resin C / phenol novolak resin; “GPH-103” manufactured by Nippon Kayaku Co., Ltd.
(17) Curing accelerator / imidazole compound; “2PHZ” manufactured by Shikoku Kasei Kogyo Co., Ltd.
(18) Coupling agent / epoxysilane coupling agent: “A-187” manufactured by GE Toshiba Silicone

< Reference Example 1>
(1) Preparation of resin varnish 33.1 parts by weight of epoxy resin A, 6.7 parts by weight of phenol resin A, 0.2 parts by weight of curing accelerator, and 0.3 parts by weight of coupling agent were dissolved and dispersed in methyl ethyl ketone. . Furthermore, 39.8 parts by weight of inorganic filler A and 19.9 parts by weight of inorganic filler E were added and stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.

(2) Preparation of prepreg The above resin varnish was impregnated into glass woven fabric 1 (thickness 94 μm, manufactured by Nitto Boseki Co., Ltd., WEA-2116), dried in a heating furnace at 150 ° C. for 2 minutes, and resin composition in the prepreg A prepreg 1 having a material content of about 50% by weight was obtained. Similarly, using glass woven fabric 2 (thickness 24 μm, manufactured by Nitto Boseki Co., Ltd., WEA-1037), prepreg 2 having a resin composition content of about 60% was obtained. Similarly, using glass woven fabric 3 (thickness 20 μm, manufactured by Nitto Boseki Co., Ltd., WEA-1027), a prepreg 3 having a resin composition content of about 75% was obtained.

(3) Production of Laminate Sheet Two prepregs 1 are stacked, 18 μm copper foil (made by Mitsui Kinzoku Co., Ltd.) is stacked on both sides, and heated and pressure-molded at a pressure of 4 MPa and a temperature of 200 ° C. for 2 hours to form both sides. A laminate 1 having a thickness of 0.2 mm having a copper foil was obtained. Similarly, a 12 μm copper foil (made by Mitsui Kinzoku Co., Ltd.) is stacked on both sides of the prepreg 2 and heated and pressed at a pressure of 4 MPa and a temperature of 200 ° C. for 2 hours to laminate a copper foil on both sides with a thickness of 30 μm. Plate 2 was obtained.

(4) Production of multilayer printed wiring board After the through-hole processing was performed on the laminated board 1 obtained above using a 0.1 mm drill bit, the through-hole was filled by plating. Further, a circuit was formed on both sides by etching and used as an inner layer circuit board. The prepreg 3 obtained above is overlapped on the front and back of the inner layer circuit board, and a 12 μm copper foil (made by Mitsui Kinzoku Co., Ltd.) is overlapped on both sides, followed by heat-pressure molding at a pressure of 3 MPa and a temperature of 200 ° C. for 2 hours. Thus, a multilayer printed wiring board was obtained.

< Reference Example 2>
22.4 parts by weight of epoxy resin B, 12.4 parts by weight of phenol resin B, 0.2 parts by weight of curing accelerator, and 0.3 parts by weight of coupling agent were dissolved and dispersed in methyl ethyl ketone. Furthermore, 39.8 parts by weight of the inorganic filler B and 19.9 parts by weight of the inorganic filler F were added and stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Example 3>
8.4 parts by weight of epoxy resin C, 15.0 parts by weight of cyanate resin B, 6.6 parts by weight of phenol resin C, and 0.3 parts by weight of silane coupling agent were dissolved and dispersed in methyl ethyl ketone. Furthermore, 29.9 parts by weight of inorganic filler B and 39.8 parts by weight of inorganic filler G were added and stirred for 30 minutes using a high-speed stirring device to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Example 4>
11.2 parts by weight of epoxy resin C, 20.0 parts by weight of cyanate resin, 8.8 parts by weight of phenol resin C, and 0.3 parts by weight of a coupling agent were dissolved and dispersed in methyl ethyl ketone. Further, 19.9 parts by weight of the inorganic filler C, 9.9 parts by weight of the inorganic filler D, and 29.9 parts by weight of the inorganic filler G were added, and the mixture was stirred for 10 minutes using a high-speed stirrer. A 60% by weight resin varnish was prepared.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Example 5>
11.2 parts by weight of epoxy resin C, 20.0 parts by weight of cyanate resin, 8.8 parts by weight of phenol resin C, and 0.3 parts by weight of a coupling agent were dissolved and dispersed in methyl ethyl ketone. Furthermore, 59.7 parts by weight of inorganic filler A was added, and the mixture was stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Comparative Example 1>
11.2 parts by weight of epoxy resin C, 20.0 parts by weight of cyanate resin, and 8.8 parts by weight of phenol resin C were dissolved and dispersed in methyl ethyl ketone. Furthermore, 39.8 parts by weight of the inorganic filler H and 19.9 parts by weight of the inorganic filler F were added and stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Comparative example 2>
11.2 parts by weight of epoxy resin C, 20.0 parts by weight of cyanate resin, and 8.8 parts by weight of phenol resin C were dissolved and dispersed in methyl ethyl ketone. Furthermore, 39.8 parts by weight of the inorganic filler I and 19.9 parts by weight of the inorganic filler F were added and stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Comparative Example 3>
11.2 parts by weight of epoxy resin C, 20.0 parts by weight of cyanate resin, and 8.8 parts by weight of phenol resin C were dissolved and dispersed in methyl ethyl ketone. Furthermore, 9.9 parts by weight of the inorganic filler H and 49.8 parts by weight of the inorganic filler F were added and stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Comparative Example 4>
11.2 parts by weight of epoxy resin C, 20.0 parts by weight of cyanate resin, and 8.8 parts by weight of phenol resin C were dissolved and dispersed in methyl ethyl ketone. Furthermore, 9.9 parts by weight of the inorganic filler I and 49.8 parts by weight of the inorganic filler F were added and stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Comparative Example 5>
19.2 parts by weight of epoxy resin B, 10.6 parts by weight of phenol resin B, 0.2 parts by weight of curing accelerator, and 0.3 parts by weight of silane coupling agent were dissolved and dispersed in methyl ethyl ketone. Furthermore, 69.7 parts by weight of inorganic filler G was added, and the mixture was stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

<Comparative Example 6>
33.1 parts by weight of epoxy resin A, 6.7 parts by weight of phenol resin A, 0.2 parts by weight of curing accelerator, and 0.3 parts by weight of coupling agent were dissolved and dispersed in methyl ethyl ketone. Furthermore, 59.7 parts by weight of inorganic filler D was added and stirred for 30 minutes using a high-speed stirrer to prepare a resin varnish having a solid content of 60% by weight.
Using this resin varnish, a prepreg, a laminate, and a multilayer printed wiring board were obtained in the same manner as in Reference Example 1.

  The characteristics of the laminates and multilayer printed wiring boards obtained in the examples and comparative examples were evaluated. The results are shown in Tables 1 and 2.

The evaluation method will be described below.

(1) The entire surface of the copper foil of the laminate 1 having a thermal expansion coefficient thickness of 0.2 mm is etched, a test piece of 4 mm × 20 mm is cut out from the obtained laminate, and the condition is 10 ° C./min using TMA. The linear expansion coefficient (average linear expansion coefficient) in the plane direction at 50 ° C. to 150 ° C. was measured.

(2) Formability The cross section of the circuit portion of the obtained multilayer printed wiring board was observed to confirm the circuit embedding property. Each code | symbol is as follows.
○: No abnormality.
X: There is an embedding defect.

(3) Drill workability The state of the cutting edge of the laminate 1 having a thickness of 0.2 mm was evaluated after drilling 2000 times at 300,000 revolutions using a 0.1 mm drill blade. Each code | symbol is as follows.
○: Drill blade can be regenerated by regrinding ×: Drill blade cannot be regenerated

(4) Solder heat resistance A 50 mm square sample was cut out from the obtained multilayer printed wiring board, 3/4 etched, treated at 121 ° C. for 2 hours using a pressure cooker, immersed in 288 ° C. solder for 30 seconds, and swollen The presence or absence of measling was observed. Each code | symbol is as follows.
○: No abnormality ×: Swelling and mesuring

(5) Flame retardance test According to UL-94 standard, the copper foil of the 30-micrometer-thick laminated board 2 was etched, and the test piece according to a standard was produced. The test piece was used and measured by the vertical method.

Examples 1-5 use the resin composition containing the substantially cubic boehmite of this invention. Good overall evaluation. On the other hand, since Comparative Example 1 and Comparative Example 2 did not use substantially cubic boehmite, problems were observed during the formation of the multilayer printed wiring board. In Comparative Example 3 and Comparative Example 4, the drilling workability and flame retardancy were lowered because the blending amount of spherical silica was increased in order to improve the moldability of Comparative Examples 1 and 2. Since Comparative Example 5 did not use boehmite and only silica having high hardness was used, drill workability was lowered. Since Comparative Example 6 uses only aluminum hydroxide, the moldability and heat resistance were poor.

According to the present invention, it is possible to produce a laminated board and a multilayer printed wiring board having no moisture absorption deterioration, excellent insulation reliability, and excellent thermal dimensional stability. These are useful for multilayer printed wiring boards that support high-density mounting in response to demands for higher functionality of electronic devices.

Claims (9)

A resin composition comprising substantially cubic boehmite as an essential component, wherein the content of the substantially cubic boehmite is 10 wt% or more and 70 wt% or less of the whole resin composition, and a cyanate resin is used. A resin composition characterized by containing. 2. The resin composition according to claim 1, wherein the substantially cubic boehmite has a BET specific surface area of 1 m 2 / g or more and 20 m 2 / g or less. The resin composition according to claim 1 or 2, wherein an average particle diameter of the substantially cubic boehmite is 0.5 µm or more and 10 µm or less.   The resin composition according to any one of claims 1 to 3, further comprising silica. The resin composition according to claim 4, wherein the silica has an average particle size of 0.1 μm or more and 2 μm or less. A prepreg obtained by impregnating a base material with the resin composition according to any one of claims 1 to 5. A laminate obtained by molding one or more prepregs according to claim 6. A multilayer printed wiring board using the prepreg according to claim 6 and / or the laminated board according to claim 7.   A semiconductor device comprising a semiconductor element mounted on the multilayer printed wiring board according to claim 8.