KR102489450B1 - Prepreg and its manufacturing method, laminated board, printed wiring board and semiconductor package - Google Patents

Abstract

It is a prepreg obtained through the following processes 1-3. Step 1: This is a step of obtaining a prepreg precursor. The prepreg precursor is obtained by B-staging a thermosetting resin composition, and the B-staging is performed by impregnating a base material with the thermosetting resin composition and then performing heat treatment. . Process 2: A process of cooling the prepreg precursor obtained in Process 1. Step 3: This is a step of obtaining a prepreg. The prepreg is obtained by subjecting the prepreg precursor cooled in step 2 to a surface heating treatment, and the surface heating treatment is a treatment of raising the surface temperature of the prepreg precursor. .

Description

Prepreg and its manufacturing method, laminated board, printed wiring board and semiconductor package

The present invention relates to a prepreg, a manufacturing method thereof, a laminate, a printed wiring board, and a semiconductor package.

In recent years, miniaturization, weight reduction, and multifunctionalization of electronic devices have progressed further, and with this, high integration of LSI (Large Scale Integration), chip parts, etc. has progressed, and their shapes are also rapidly changing to multi-pin and miniaturization. For this reason, in order to improve the mounting density of electronic components, development of fine wiring of a multilayer printed wiring board is advancing. As a method of manufacturing a multilayer printed wiring board that meets these requirements, for example, prepreg or the like is used as an insulating layer, and only necessary portions are formed by, for example, laser irradiation. Via holes (hereinafter also referred to as "laser vias") ), a multilayer printed wiring board of a build-up method in which wiring layers are formed while being connected is becoming mainstream as a method suitable for weight reduction, miniaturization, and fine wiring.

In a multilayer printed wiring board, it is important to have high electrical connection reliability and excellent high-frequency characteristics between multiple layers of wiring patterns formed at a fine wiring pitch, and high connection reliability with semiconductor chips is required. Particularly in recent years, in motherboards such as multifunctional mobile phone terminals, thinning and wiring density have become remarkable, and laser vias provided for interlayer connection are required to have a reduced diameter.

In the case of interlayer connection with a small-diameter laser via, one of the important characteristics is dimensional stability of the substrate. In the case of multilayer wiring, a plurality of heat amounts and stress during lamination are applied to each substrate. Therefore, when the dimensional variation of the substrate itself, in particular, the variation in dimensional variation of each substrate due to thermal history is large, displacement of the laser via occurs every time it is stacked, which may cause defects such as a decrease in connection reliability. From this, a board|substrate with small fluctuation|variation of the amount of dimensional change is calculated|required.

For example, in Patent Document 1, for the purpose of improving the compatibility between layers in a multilayer printed wiring board, a core containing a base material containing a pre-cured thermosetting resin and having a first surface and a second surface; , A prepreg comprising a first adhesive layer and a second adhesive layer formed on each of the first and second surfaces of the core is disclosed.

Japanese Unexamined Patent Publication No. 2002-103494

However, since the prepreg of Patent Literature 1 contains a pre-cured thermosetting resin as a core, there is a problem that wiring embeddability and the like are poor. In addition, since the prepreg of Patent Literature 1 requires a plurality of layers having different degrees of curing, a complicated production process is required, and a prepreg with small fluctuations in dimensional change obtained by a simpler method is desired.

Therefore, an object of the present invention is to provide a prepreg with excellent moldability and small fluctuations in dimensional change, a manufacturing method thereof, a laminated board, a printed wiring board, and a semiconductor package.

As a result of intensive research to achieve the above object, the inventors of the present invention have found that prepregs produced through a specific heat treatment process have excellent moldability and small fluctuations in the amount of dimensional change, and have developed the present invention. reached completion. The present invention relates to the following [1] to [10].

[1] A prepreg obtained through steps 1 to 3 below.

Step 1: This is a step of obtaining a prepreg precursor. The prepreg precursor is obtained by B-staging a thermosetting resin composition, and the B-staging is performed by impregnating a base material with the thermosetting resin composition and then performing heat treatment. .

Process 2: A process of cooling the prepreg precursor obtained in Process 1.

Step 3: This is a step of obtaining a prepreg. The prepreg is obtained by subjecting the prepreg precursor cooled in step 2 to a surface heating treatment, and the surface heating treatment is a treatment of raising the surface temperature of the prepreg precursor. .

[2] The prepreg according to [1] above, wherein the surface heat treatment in step 3 is a treatment for raising the surface temperature of the prepreg precursor by 5 to 110°C.

[3] The prepreg according to [1] or [2], wherein the surface heating treatment in step 3 is a treatment for heating the surface temperature of the prepreg precursor to 20 to 130°C.

[4] The prepreg according to any one of [1] to [3], wherein the surface heat treatment in Step 3 is a treatment of heating the prepreg precursor in an environment of 200 to 700°C.

[5] The prepreg according to any one of [1] to [4] above, wherein the heating time of the surface heat treatment in Step 3 is 1.0 to 10.0 seconds.

[6] The prepreg according to any one of [1] to [5], wherein the substrate is a glass cloth.

[7] A laminate obtained by laminating and molding the prepreg according to any one of [1] to [6] above and metal foil.

[8] A printed wiring board comprising the prepreg according to any one of [1] to [6] above or the laminated board according to [7] above.

[9] A semiconductor package formed using the printed wiring board described in [8] above.

[10] A method for producing a prepreg according to any one of [1] to [6] above, comprising steps 1 to 3 below.

Step 1: This is a step of obtaining a prepreg precursor. The prepreg precursor is obtained by B-staging a thermosetting resin composition, and the B-staging is performed by impregnating a base material with the thermosetting resin composition and then performing heat treatment. .

Process 2: A process of cooling the prepreg precursor obtained in Process 1.

Step 3: This is a step of obtaining a prepreg. The prepreg is obtained by subjecting the prepreg precursor cooled in step 2 to a surface heating treatment, and the surface heating treatment is a treatment of raising the surface temperature of the prepreg precursor. .

ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide a prepreg with excellent moldability and small fluctuations in dimensional change, a manufacturing method thereof, a laminated board, a printed wiring board, and a semiconductor package.

1 is a schematic diagram of an evaluation board used for measuring fluctuations in dimensional change amounts in Examples.

The lower limit and upper limit of a numerical range in this specification may be combined with the lower limit and upper limit of each other numerical range at will. Embodiments which arbitrarily combined the descriptions in this specification are also included in the present invention.

[Prepreg]

The prepreg of the present invention is a prepreg obtained through the following steps 1 to 3.

Step 1: This is a step of obtaining a prepreg precursor. The prepreg precursor is obtained by B-staging a thermosetting resin composition, and the B-staging is performed by impregnating a base material with the thermosetting resin composition and then performing heat treatment. .

Process 2: A process of cooling the prepreg precursor obtained in Process 1.

Step 3: This is a step of obtaining a prepreg. The prepreg is obtained by subjecting the prepreg precursor cooled in step 2 to a surface heating treatment, and the surface heating treatment is a treatment of raising the surface temperature of the prepreg precursor. .

First, the base material and thermosetting resin composition used in the prepreg of the present invention will be described, and then the prepreg manufacturing method of the present invention will be described.

In the present invention, the B-stage refers to a state in which the thermosetting resin composition is semi-cured.

<Description>

As the base material containing the prepreg of the present invention, well-known base materials used in laminates for various electric insulating materials can be used, and are not particularly limited.

As the substrate, natural fibers such as paper and cotton linters; inorganic fibers such as glass fibers and asbestos; organic fibers such as aramid, polyimide, polyvinyl alcohol, polyester, tetrafluoroethylene, and acryl; mixtures thereof; and the like. Among these, glass fiber is preferable. As the glass fiber base material, a glass woven fabric (glass cloth) is preferable, for example, a woven fabric using E glass, C glass, D glass, S glass, etc., or a glass woven fabric obtained by bonding short fibers with an organic binder; What mixed glass fiber and cellulose fiber, etc. are mentioned. More preferably, it is a glass woven fabric using E glass.

These substrates have shapes such as woven fabrics, non-woven fabrics, rovings, chopped strand mats, and surfacing mats. In addition, the material and shape are selected according to the intended use and performance of the molding, and one type may be used alone, or two or more types of material and shape may be combined as necessary.

The thickness of the substrate is, for example, 0.01 to 0.5 mm, preferably 0.015 to 0.2 mm, and more preferably 0.02 to 0.1 mm from the viewpoint of enabling formability and high-density wiring. From the viewpoint of heat resistance, moisture resistance, processability, etc., these substrates are preferably surface-treated with a silane coupling agent or mechanically subjected to carding treatment.

<Thermosetting resin composition>

The thermosetting resin composition containing the prepreg of the present invention may be, for example, a thermosetting resin composition containing a known thermosetting resin used in prepregs for printed wiring boards, and is not particularly limited.

The thermosetting resin composition contains (A) a thermosetting resin, and preferably contains at least one selected from the group consisting of (B) a curing agent, (C) a curing accelerator, and (D) an inorganic filler, and (B) It is more preferable to contain a curing agent, (C) a curing accelerator, and (D) an inorganic filler.

Hereinafter, each component that a thermosetting resin composition may contain is demonstrated.

((A) thermosetting resin)

(A) The thermosetting resin is not particularly limited, and an arbitrary one can be appropriately selected and used from those conventionally used as thermosetting resins.

(A) Examples of the thermosetting resin include epoxy resins, phenol resins, maleimide compounds, cyanate resins, isocyanate resins, benzoxazine resins, oxetane resins, amino resins, unsaturated polyester resins, allyl resins, dicyclopentadiene resins, A silicone resin, a triazine resin, a melamine resin, etc. are mentioned. Among these, from the viewpoints of moldability and electrical insulation, epoxy resins and maleimide compounds are preferable.

(A) A thermosetting resin may be used individually by 1 type, and may use 2 or more types together.

The epoxy equivalent of the epoxy resin is preferably 100 to 500 g/eq, more preferably 150 to 400 g/eq, still more preferably 200 to 350 g/eq. Here, the epoxy equivalent is the mass (g/eq) of the resin per epoxy group, and can be measured according to the method specified in JIS K 7236.

As an epoxy resin, a glycidyl ether type epoxy resin, a glycidyl amine type epoxy resin, a glycidyl ester type epoxy resin, etc. are mentioned. Among these, a glycidyl ether type epoxy resin is preferable.

Epoxy resins are classified into various types of epoxy resins also depending on the difference in the main skeleton, and in each of the above types of epoxy resins, further bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, etc. Suzy; Biphenylaralkyl novolak type epoxy resin, phenol novolak type epoxy resin, alkylphenol novolak type epoxy resin, cresol novolak type epoxy resin, naphtholalkylphenol copolymerization novolak type epoxy resin, naphthol aralkylcresol copolymerization novolac type epoxy resins, novolac-type epoxy resins such as bisphenol A novolak-type epoxy resins and bisphenol F novolac-type epoxy resins; stilbene type epoxy resin; triazine backbone-containing epoxy resins; fluorene backbone-containing epoxy resins; naphthalene type epoxy resin; Anthracene type epoxy resin; triphenylmethane type epoxy resin; Biphenyl type epoxy resin; xylylene type epoxy resin; They are classified into alicyclic epoxy resins such as dicyclopentadiene type epoxy resins.

Among these, from the viewpoints of moldability and insulation reliability, novolac-type epoxy resins are preferred, and biphenylaralkyl novolak-type epoxy resins are more preferred.

As the maleimide compound, a maleimide compound (a1) having an N-substituted maleimide group (hereinafter, also referred to as "maleimide compound (a1)") is preferable.

Specific examples of the maleimide compound (a1) include N,N'-ethylenebismaleimide, N,N'-hexamethylenebismaleimide, bis(4-maleimidecyclohexyl)methane, and 1,4- aliphatic hydrocarbon group-containing maleimides such as bis(maleimidemethyl)cyclohexane; N,N'-(1,3-phenylene)bismaleimide, N,N'-[1,3-(2-methylphenylene)]bismaleimide, N,N'-[1,3-(4 -methylphenylene)]bismaleimide, N,N'-(1,4-phenylene)bismaleimide, bis(4-maleimidephenyl)methane, bis(3-methyl-4-maleimidephenyl)methane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethanebismaleimide, bis(4-maleimidephenyl)ether, bis(4-maleimidephenyl)sulfone, bis(4 -maleimidephenyl) sulfide, bis(4-maleimidephenyl)ketone, 1,4-bis(4-maleimidephenyl)cyclohexane, 1,4-bis(maleimidemethyl)cyclohexane, 1,3- Bis(4-maleimidephenoxy)benzene, 1,3-bis(3-maleimidephenoxy)benzene, bis[4-(3-maleimidephenoxy)phenyl]methane, bis[4-(4-maleimidephenoxy)benzene Midphenoxy) phenyl] methane, 1,1-bis [4- (3-maleimide phenoxy) phenyl] ethane, 1,1-bis [4- (4-maleimide phenoxy) phenyl] ethane, 1, 2-bis[4-(3-maleimidephenoxy)phenyl]ethane, 1,2-bis[4-(4-maleimidephenoxy)phenyl]ethane, 2,2-bis[4-(3-maleimidephenoxy)phenyl]ethane Midphenoxy) phenyl] propane, 2,2-bis [4- (4-maleimide phenoxy) phenyl] propane, 2,2-bis [4- (3-maleimide phenoxy) phenyl] butane, 2, 2-bis[4-(4-maleimidephenoxy)phenyl]butane, 2,2-bis[4-(3-maleimidephenoxy)phenyl]-1,1,1,3,3,3-hexa Fluoropropane, 2,2-bis[4-(4-maleimidephenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 4,4-bis(3-maleimide Phenoxy)biphenyl, 4,4-bis(4-maleimidephenoxy)biphenyl, bis[4-(3-maleimidephenoxy)phenyl]ketone, bis[4-(4-maleimidephenoxy) phenyl] ketone, 2,2'-bis(4-maleimidephenyl)disulfide, bis(4-maleimidephenyl)disulfide, bis[4-(3-maleimidephenoxy)phenyl]sulfide, bis[ 4-(4-maleimidephenoxy)phenyl]sulfide, bis[4-(3-maleimidephenoxy)phenyl]sulfoxide, bis[4-(4-maleimidephenoxy)phenyl]sulfoxide, bis [4-(3-maleimidephenoxy)phenyl]sulfone, bis[4-(4-maleimidephenoxy)phenyl]sulfone, bis[ 4-(3-maleimidephenoxy)phenyl]ether, bis[4-(4-maleimidephenoxy)phenyl]ether, 1,4-bis[4-(4-maleimidephenoxy)-α,α -Dimethylbenzyl]benzene, 1,3-bis[4-(4-maleimidephenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis[4-(3-maleimidephenoxy)-α ,α-dimethylbenzyl]benzene, 1,3-bis[4-(3-maleimidephenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis[4-(4-maleimidephenoxy) -3,5-dimethyl-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-maleimidephenoxy)-3,5-dimethyl-α,α-dimethylbenzyl]benzene, 1, 4-bis[4-(3-maleimidephenoxy)-3,5-dimethyl-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(3-maleimidephenoxy)-3,5 -Dimethyl-α,α-dimethylbenzyl] benzene and aromatic hydrocarbon group-containing maleimides such as polyphenylmethane maleimide.

Among these, bis(4-maleimidephenyl)methane, bis(4-maleimidephenyl)sulfone, bis(4-maleimidephenyl)sulfide, bis(4- Maleimide phenyl) disulfide, N,N'-(1,3-phenylene)bismaleimide, and 2,2-bis[4-(4-maleimidephenoxy)phenyl]propane are preferable and are inexpensive. In, bis(4-maleimidephenyl)methane and N,N'-(1,3-phenylene)bismaleimide are preferable, and from the viewpoint of solubility in solvents, bis(4-maleimidephenyl)methane is particularly preferred.

The maleimide compound is preferably a maleimide compound having an N-substituted maleimide group obtained by reacting a maleimide compound (a1), a monoamine compound (a2) having an acidic substituent, and a diamine compound (a3).

Examples of the monoamine compound (a2) having an acidic substituent include o-aminophenol, m-aminophenol, p-aminophenol, o-aminobenzoic acid, m-aminobenzoic acid, p-aminobenzoic acid, and o-aminobenzenesulfonic acid. , m-aminobenzenesulfonic acid, p-aminobenzenesulfonic acid, 3,5-dihydroxyaniline, 3,5-dicarboxyaniline, and the like.

As the diamine compound (a3), for example, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenylpropane, 2,2'-bis[ 4,4'-diaminodiphenyl] propane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-diethyl-4,4'-diaminodiphenylmethane, 3 ,3'-dimethyl-4,4'-diaminodiphenylethane, 3,3'-diethyl-4,4'-diaminodiphenylethane, 4,4'-diaminodiphenyl ether, 4,4 '-diaminodiphenylthioether, 3,3'-dihydroxy-4,4'-diaminodiphenylmethane, 2,2',6,6'-tetramethyl-4,4'-diaminodi Phenylmethane, 3,3'-dichloro-4,4'-diaminodiphenylmethane, 3,3'-dibromo-4,4'-diaminodiphenylmethane, 2,2',6,6' -Tetramethylchloro-4,4'-diaminodiphenylmethane, 2,2',6,6'-tetrabromo-4,4'-diaminodiphenylmethane, etc. are mentioned. Among these, from the viewpoint of being inexpensive, 4,4'-diaminodiphenylmethane and 3,3'-diethyl-4,4'-diaminodiphenylmethane are preferred, and from the viewpoint of solubility in solvents, 4, 4'-diaminodiphenylmethane is more preferred.

In the reaction of the maleimide compound (a1), the monoamine compound (a2) having an acidic substituent, and the diamine compound (a3), the amount of the three characters used is the monoamine compound (a2) and diamine compound (a3) having an acidic substituent It is preferable that the relationship between the sum of primary amino group equivalents [described as -NH ₂ group equivalents] and the maleimide group equivalent of the maleimide compound (a1) satisfies the following formula.

0.1 ≤ [maleimide group equivalent]/[total of -NH ₂ group equivalents] ≤ 10

When [maleimide group equivalent]/[total sum of -NH ₂ group equivalents] is set to 0.1 or more, gelation and heat resistance do not decrease, and when set to 10 or less, solubility to organic solvents, metal foil adhesion and heat resistance are improved. This is preferable because there is no deterioration.

From the same point of view, more preferably

1 ≤ [maleimide group equivalent]/[total sum of -NH ₂ group equivalents] ≤ 9, more preferably

2 ≤ [maleimide group equivalent]/[total sum of -NH ₂ group equivalents] ≤ 8 is satisfied.

The content of the thermosetting resin (A) in the thermosetting resin composition is preferably 15 to 80 parts by mass, more preferably 25 to 70 parts by mass, and still more preferably 35 to 60 parts by mass, based on 100 parts by mass of the resin component in the thermosetting resin composition. . The resin component in the thermosetting resin composition is, for example, (A) thermosetting resin, (B) curing agent, (C) curing accelerator, and the like.

((B) curing agent)

The thermosetting resin composition may contain (B) a curing agent in order to cure the (A) thermosetting resin. (B) The curing agent is not particularly limited, and any curing agent can be appropriately selected and used from those conventionally used as curing agents for thermosetting resins.

(B) The hardening|curing agent may be used individually by 1 type, and may use 2 or more types together.

As the (B) curing agent, when an epoxy resin is used as the (A) thermosetting resin, a phenol resin curing agent, an acid anhydride curing agent, an amine curing agent, dicyandiamide, a cyanate resin curing agent, and the like are exemplified. Among these, from the viewpoint of moldability and insulation reliability, a phenol resin-based curing agent is preferable.

The phenolic resin-based curing agent is not particularly limited as long as it is a phenolic resin having two or more phenolic hydroxyl groups in one molecule, and resorcin, catechol, bisphenol A, bisphenol F, biphenol, etc. having two phenolic hydroxyl groups in one molecule compound; aralkyl type phenol resins; dicyclopentadiene type phenol resin; triphenylmethane type phenol resin; novolac-type phenol resins such as phenol novolak resins, cresol novolak resins, and aminotriazine-modified novolac-type phenol resins; resol type phenolic resin; copolymerized phenolic resins of benzaldehyde-type phenol and aralkyl-type phenol; p-xylylene and/or m-xylylene-modified phenolic resins; melamine-modified phenolic resins; terpene-modified phenolic resins; dicyclopentadiene type naphthol resins; cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified phenolic resins; A biphenyl type phenol resin etc. are mentioned. Among these, a novolak-type phenol resin is preferable, and a cresol novolak resin is more preferable.

As the acid anhydride curing agent, phthalic anhydride, 3-methyl-1,2,3,6-tetrahydrophthalic anhydride, 4-methyl-1,2,3,6-tetrahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride , 4-methylhexahydrophthalic anhydride, methyl-3,6-endomethylene-1,2,3,6-tetrahydrophthalic anhydride, benzophenone tetracarboxylic dianhydride, methylhymic acid, and the like.

Examples of the amine curing agent include chain aliphatic polyamines such as diethylenetriamine, triethylenetetramine, and diethylaminopropylamine; cyclic aliphatic polyamines such as N-aminoethylpiperazine and isophoronediamine; aliphatic diamines having aromatic rings such as m-xylylenediamine; aromatic amines such as m-phenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone; A guanyl urea etc. are mentioned.

As the cyanate resin curing agent, 2,2-bis(4-cyanatophenyl)propane, bis(4-cyanatophenyl)ethane, bis(3,5-dimethyl-4-cyanatophenyl)methane, 2,2- Bis(4-cyanatophenyl)-1,1,1,3,3,3-hexafluoropropane, α,α'-bis(4-cyanatophenyl)-m-diisopropylbenzene, phenol addition dicy A cyanate ester compound of a clopentadiene polymer, a phenol novolak type cyanate ester compound, a cresol novolak type cyanate ester compound, etc. are mentioned.

When the thermosetting resin composition contains the (B) curing agent, the content thereof is preferably 15 to 80 parts by mass, more preferably 25 to 70 parts by mass, and 35 to 60 parts by mass, based on 100 parts by mass of the resin component in the thermosetting resin composition. Addition is more preferred.

(A) In the case of using an epoxy resin as the thermosetting resin, the equivalent ratio of the active hydrogen to the epoxy group derived from the epoxy resin and the epoxy group derived from the (B) curing agent (active hydrogen/epoxy group) is preferably 0.5 to 3, 0.7 to 2.5 are more preferable, and 0.8 to 2.2 are still more preferable.

((C) Curing Accelerator)

(C) The curing accelerator is not particularly limited, and an arbitrary one can be appropriately selected and used from those conventionally used as curing accelerators for thermosetting resins.

(C) A hardening accelerator may be used individually by 1 type, and may use 2 or more types together.

(C) As a hardening accelerator, it is a phosphorus compound; imidazole compounds and their derivatives; tertiary amine compounds; A quaternary ammonium compound etc. are mentioned. Among these, imidazole compounds and derivatives thereof are preferred from the viewpoint of accelerating the curing reaction.

As the imidazole compound and its derivatives, 2-methylimidazole, 2-ethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1,2-dimethyl Imidazole, 2-ethyl-1-methylimidazole, 1,2-diethylimidazole, 1-ethyl-2-methylimidazole, 2-ethyl-4-methylimidazole, 4-ethyl -2-methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2 -Ethylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole sol, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 2,4-diamino-6- [2'-Methylimidazolyl-(1')]ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]ethyl-s-triazine imidazole compounds such as azine and 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]ethyl-s-triazine; an adduct of the imidazole compound and trimellitic acid; an adduct of the imidazole compound and isocyanuric acid; an adduct of the imidazole compound and hydrobromic acid; The addition reaction product of the said imidazole compound and an epoxy resin, etc. are mentioned.

When the thermosetting resin composition contains the (C) curing accelerator, the content thereof is preferably 0.01 to 2 parts by mass, more preferably 0.02 to 1.5 parts by mass, and 0.04 to 1 part by mass, based on 100 parts by mass of the resin component in the thermosetting resin composition. Mass part is more preferable.

((D) inorganic filler)

It is preferable that the thermosetting resin composition further contains (D) an inorganic filler from viewpoints, such as low thermal expansibility.

(D) The inorganic filler is not particularly limited, and an arbitrary filler can be appropriately selected and used from those conventionally used as inorganic fillers in thermosetting resin compositions.

(D) An inorganic filler may be used individually by 1 type, and may use 2 or more types together.

(D) As the inorganic filler, silica, alumina, barium sulfate, talc, mica, kaolin, boehmite, beryllia, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum hydroxide , aluminum borate, aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, zinc borate, zinc stannate, zinc oxide, titanium oxide, silicon carbide, silicon nitride, boron nitride, clay such as fired clay, short glass fiber, glass powder, hollow Glass beads etc. are mentioned. As glass, E glass, T glass, D glass, etc. are mentioned. Among these, from a viewpoint of low thermal expansibility, silica is preferable.

Examples of the silica include precipitated silica produced by a wet method and having a high moisture content, and dry-processed silica produced by a dry method and containing almost no bound water or the like. As dry-process silica, further, depending on the manufacturing method, crushed silica, fumed silica, fused silica (fused spherical silica), etc. are mentioned. Among these, fused silica is preferable from the viewpoint of low thermal expansibility and high fluidity when filled into a resin.

Silica is preferably a silica surface-treated with a silane coupling agent.

Examples of the silane coupling agent include aminosilane coupling agents, epoxysilane coupling agents, phenylsilane coupling agents, alkylsilane coupling agents, alkenylsilane coupling agents, alkynylsilane coupling agents, haloalkylsilane coupling agents, Siloxane coupling agent, hydrosilane coupling agent, silazane coupling agent, alkoxysilane coupling agent, chlorosilane coupling agent, (meth)acrylsilane coupling agent, aminosilane coupling agent, isocyanurate silane coupling agent A ring agent, a ureidsilane type coupling agent, a mercaptosilane type coupling agent, a sulfide silane type coupling agent, an isocyanate silane type coupling agent, etc. are mentioned.

(D) The average particle size of the inorganic filler is preferably 0.01 to 6 μm, more preferably 0.1 to 5 μm, still more preferably 0.5 to 4 μm, particularly preferably 1 to 3 μm.

In the present specification, the average particle diameter is the particle diameter at a point corresponding to 50% of the volume when the cumulative frequency distribution curve by the particle diameter is obtained with the total volume of the particles as 100%. Particle size distribution measurement using the laser diffraction scattering method It can be measured with a device, etc.

When the thermosetting resin composition contains (D) the inorganic filler, its content is preferably 10 to 300 parts by mass, preferably 50 to 250 parts by mass, based on 100 parts by mass of the resin component in the thermosetting resin composition, from the viewpoint of low thermal expansibility and moldability. It is more preferably 100 to 220 parts by mass, particularly preferably 130 to 200 parts by mass.

(other ingredients)

The thermosetting resin composition may contain other components such as an organic filler, a flame retardant, a thermoplastic resin, an ultraviolet absorber, an antioxidant, a photopolymerization initiator, an optical whitening agent, and an adhesion improver within a range that does not impair the effects of the present invention. .

(organic solvent)

The thermosetting resin composition may be in a varnish state (hereinafter also referred to as "resin varnish") containing an organic solvent from the viewpoint of facilitating prepreg production.

Examples of organic solvents include alcohol solvents such as methanol, ethanol, propanol, butanol, methyl cellosolve, butyl cellosolve, and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ester solvents such as butyl acetate and propylene glycol monomethyl ether acetate; ether solvents such as tetrahydrofuran; Aromatic solvents, such as toluene, xylene, and mesitylene; nitrogen atom-containing solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; Sulfur atom containing solvents, such as dimethyl sulfoxide, etc. are mentioned. Among these, from the viewpoint of solubility and appearance after application, ketone solvents are preferred, and methyl ethyl ketone is more preferred.

An organic solvent may be used individually by 1 type, and may use 2 or more types together.

The solid content concentration in the resin varnish is preferably 10 to 80% by mass, more preferably 20 to 75% by mass, still more preferably 40 to 75% by mass, from the viewpoint of handleability.

In the present specification, "solid content" is a non-volatile component excluding volatilizing substances such as water and solvent contained in the thermosetting resin composition, and indicates a component remaining without volatilization when the thermosetting resin composition is dried, and also at around 25 ° C. It also includes liquid, starch syrup and waxy forms at room temperature.

[Prepreg manufacturing method]

Next, the prepreg manufacturing method of the present invention including the steps 1 to 3 will be described.

<Process 1>

Step 1 is a step of obtaining a prepreg precursor. The prepreg precursor is obtained by B-staging a thermosetting resin composition, and the B-staging is performed by impregnating a base material with the thermosetting resin composition and then performing heat treatment. .

Although it does not specifically limit as a method of impregnating a base material with a thermosetting resin composition, A hot melt method, a solvent method, etc. are mentioned.

The hot melt method is a method of directly impregnating a base material with a thermosetting resin composition that has been reduced in viscosity by heating. For example, the thermosetting resin composition is once applied to a coated paper having excellent peelability to form a resin film, and then laminated to the base material. method, a method of directly coating the thermosetting resin composition on a base material by a die coater or the like, and the like.

The solvent method is a method in which a base material is impregnated with a thermosetting resin composition in a resin varnish state, and examples thereof include a method in which a base material is immersed in a resin varnish and then dried.

Here, in the case of applying the hot melt method, B-staging may be performed simultaneously with heating in laminating the resin film to a base material. That is, while heating the resin film and laminating it to a base material, heating may be continued as it is to B-stage the thermosetting resin composition to obtain a prepreg precursor. In that case, the heating temperature during lamination and the heating temperature during B-staging may be the same or different.

In addition, when applying the said solvent method, B-staging may be performed simultaneously with the heating at the time of drying the said resin varnish. That is, after the substrate is immersed in the resin varnish, heating may be continued as it is while drying the organic solvent by heating to B-stage the thermosetting resin composition to obtain a prepreg precursor. In that case, the heating temperature during drying and the heating temperature during B-staging may be the same or different.

The heat treatment conditions in this step are not particularly limited as long as the thermosetting resin composition can be B-staged, and may be appropriately determined depending on the type of thermosetting resin and the like. The temperature of the heat treatment may be, for example, 70 to 200°C, 80 to 150°C, or 90 to 130°C. The heat treatment time may be, for example, 1 to 30 minutes, 2 to 25 minutes, or 3 to 20 minutes. These conditions can also be referred to as lamination conditions when the above hot melt method is applied, and can also be referred to as dry conditions when the above solvent method is applied.

<Process 2>

Step 2 is a step of cooling the prepreg precursor obtained in Step 1. That is, Step 2 is a step of cooling the prepreg precursor obtained by performing the heat treatment in Step 1 to B-stage the thermosetting resin composition to a temperature lower than at least the temperature at which the heat treatment was performed.

By carrying out this step, the heat history of B-staging and cooling of the thermosetting resin composition, which is generally given when producing prepregs, is received, and the obtained prepreg precursor is free from dimensional changes that occur in conventional prepregs. It becomes inherent in the deformation etc. which become a factor.

In this way, before step 3 described later, by internalizing the deformation and the like caused by the thermal history of heating (step 1) and cooling (step 2), the elimination of the deformation and the like by step 3 and the equalization of the amount of dimensional change are effectively achieved. it becomes possible to realize In addition, the deformation resulting from the thermal history of heating (process 1) and cooling (process 2), once resolved by step 3, does not occur even if the same thermal history is applied after step 3, or even if it occurs, it is very Since it is small, the prepreg obtained according to the present invention has very small fluctuations in the amount of dimensional change.

Cooling of the prepreg precursor may be performed by natural cooling, or may be performed using a cooling device such as a blower or a cooling roll. The surface temperature of the prepreg precursor after cooling in this step is usually 5 to 80°C, preferably 8 to 50°C, more preferably 10 to 30°C, and even more preferably room temperature.

In addition, in this specification, room temperature refers to the ambient temperature without temperature control such as heating and cooling, and is generally about 15 to 25 ° C., but it may change depending on the weather, season, etc., so it is not limited to the above range. not.

<Process 3>

Step 3 is a step of obtaining a prepreg, and the prepreg is obtained by subjecting the prepreg precursor cooled in step 2 to a surface heat treatment, and the surface heat treatment is a treatment of raising the surface temperature of the prepreg precursor. .

The prepreg of the present invention becomes a prepreg with particularly small fluctuations in the amount of dimensional change by performing step 3. Although the reason for this is not clear, by this step, the amount of dimensional change is uniform by eliminating the deformation of the base material in the prepreg precursor that occurred in Step 1, Step 2, etc., and reducing the dimensional change during curing resulting from the deformation. I think it's done.

The heating method of the surface heating treatment in step 3 is not particularly limited, and there are no particular limitations, and a heating method using a panel heater, a heating method using hot air, a heating method using high frequency, a heating method using magnetic lines of force, a heating method using a laser, and the like. Combined heating methods, etc. are mentioned.

The heating conditions of the surface heat treatment are conditions in which the surface temperature of the prepreg precursor is higher than the surface temperature before the surface heat treatment, and also significantly affects various properties (eg fluidity) of the obtained prepreg. It is not particularly limited as long as it is not given, and may be appropriately determined according to the type of thermosetting resin.

The increase in the surface temperature of the prepreg precursor by surface heat treatment (that is, the absolute value of the difference between the surface temperature before surface heat treatment and the highest surface temperature reached during surface heat treatment) maintains good prepreg moldability 5 to 110°C is preferable, 20 to 90°C is more preferable, and 40 to 70°C is still more preferable from the viewpoint of reducing fluctuations in the amount of dimensional change while doing so.

As the heating temperature of the surface heat treatment, the surface temperature of the prepreg precursor is, for example, 20 to 130 ° C., preferably 40 to 130 ° C. It is 110 degreeC, More preferably, it is the range which becomes 60-90 degreeC.

In addition, the surface heat treatment is performed in step 1 from the viewpoint of maintaining good productivity of the prepreg and reducing the fluctuation of the amount of dimensional change while maintaining the prepreg in a B-stage state and maintaining good formability. It is preferable to perform the heating at a higher temperature and in a shorter time than the heating at the time of B-staging in the process. From this point of view, the surface heat treatment is preferably performed in an environment of 200 to 700 ° C., more preferably in an environment of 250 to 600 ° C., and even more preferably in an environment of 350 to 550 ° C. For example, when performing a heating method using a panel heater, the heating set temperature of the panel heater is preferably 200 to 700°C, more preferably 250 to 600°C, and still more preferably 350 to 550°C. Do.

The heating time of the surface heat treatment is from 1.0 to 1.0 from the viewpoint of maintaining good productivity of the prepreg and reducing fluctuations in the amount of dimensional change while maintaining the prepreg in a B-stage state and maintaining good formability. 10.0 seconds is preferable, 1.5 to 6.0 seconds are more preferable, and 2.0 to 4.0 seconds are still more preferable.

The prepreg obtained in Step 3 is preferably subjected to a cooling step of cooling the prepreg from the viewpoint of handleability and tackiness of the prepreg. Cooling of the prepreg may be performed by natural cooling, or may be performed using a cooling device such as a blower or a cooling roll. The prepreg temperature after cooling is usually 5 to 80°C, preferably 8 to 50°C, more preferably 10 to 30°C, and even more preferably room temperature.

In addition, you may carry out process 3 in the manufacturing process of the metal clad laminated board of this invention mentioned later. Specifically, in a state where metal foil is disposed on both surfaces of the prepreg precursor obtained in step 2, step 3 may be performed, and then the prepreg and metal foil may be laminated and molded. Conditions for laminate molding are as described in the section on the laminated sheet of the present invention described later.

The content of the thermosetting resin composition in terms of solid content in the prepreg of the present invention is preferably 20 to 90% by mass, more preferably 30 to 80% by mass, still more preferably 40 to 75% by mass.

The thickness of the prepreg of the present invention is, for example, 0.01 to 0.5 mm, preferably 0.02 to 0.2 mm, and more preferably 0.03 to 0.1 mm from the viewpoint of enabling moldability and high-density wiring.

The prepreg of the present invention obtained as described above has a standard deviation σ obtained by the following method of preferably 0.012% or less, more preferably 0.011% or less, even more preferably 0.010% or less, still more preferably It is 0.009% or less, especially 0.008% or less. The lower limit of the standard deviation σ is not particularly limited, but is usually 0.003% or more, may be 0.005% or more, may be 0.006% or more, or may be 0.007% or more.

How to Calculate Standard Deviation σ:

A copper foil having a thickness of 18 μm is piled up on both sides of one sheet of prepreg, and heat-pressing is performed at 190° C. and 2.45 MPa for 90 minutes to produce a double-sided copper clad laminate having a thickness of 0.1 mm. With respect to the double-sided copper-clad laminate board obtained in this way, perforations having a diameter of 1.0 mm are made in the surface at the positions 1 to 8 described in FIG. 1 . The distances of each of three points in the warp direction (1-7, 2-6, 3-5) and the weft direction (1-3, 8-4, 7-5) described in FIG. 1 are measured using an image measuring device, Each measurement distance is set as an initial value. After that, the outer layer copper foil is removed and heated in a dryer at 185° C. for 60 minutes. After cooling, in the same way as the initial value measurement method, the distance of 3 points each in the warp direction (1-7, 2-6, 3-5) and the weft direction (1-3, 8-4, 7-5) to measure From the rate of change of the initial value of each measured distance [(measured value after heat treatment - initial value) x 100/initial value], the average value of these rates of change is obtained, and the standard deviation σ for the average value is calculated.

Although there is no particular restriction on the image measuring device, for example, "QV-A808P1L-D" (manufactured by Mitutoyo) can be used.

[Laminate]

The laminated sheet of the present invention is formed by laminating and molding the prepreg of the present invention and metal foil.

The laminated board of the present invention can be manufactured, for example, by using one sheet of the prepreg of the present invention or stacking 2 to 20 sheets as necessary, and laminating molding in a configuration in which metal foil is disposed on one or both surfaces. In addition, the laminated board on which metal foil is arrange|positioned hereafter may be called a metal-clad laminated board.

The metal of the metal foil is not particularly limited as long as it is used for electrical insulating materials.

As the metal of the metal foil, from the viewpoint of conductivity, copper, gold, silver, nickel, platinum, molybdenum, ruthenium, aluminum, tungsten, iron, titanium, chromium, an alloy containing at least one of these metal elements is preferable, and copper , aluminum is more preferred, and copper is still more preferred. That is, it is preferable that the laminated board of this invention is a copper clad laminated board.

The thickness of the metal foil may be appropriately selected depending on the use of the printed wiring board, etc., but is preferably 0.5 to 150 μm, more preferably 1 to 100 μm, still more preferably 5 to 50 μm, and particularly preferably 5 to 30 μm. .

Moreover, you may form a plating layer by plating metal foil. The metal of the plating layer is not particularly limited as long as it can be used for plating, but at least one of copper, gold, silver, nickel, platinum, molybdenum, ruthenium, aluminum, tungsten, iron, titanium, chromium, and metal elements thereof Alloys containing

The plating method is not particularly limited, and an electrolytic plating method, an electroless plating method, or the like can be used.

As the molding conditions for the laminated board, known molding methods for laminated boards and multi-layered boards for electrical insulating materials can be applied, for example, using a multi-step press, a multi-step vacuum press, continuous molding, an autoclave molding machine, etc., at a temperature of 100 to 250 °C. It can be molded under the conditions of °C, pressure of 0.2 to 10 MPa, and heating time of 0.1 to 5 hours.

In addition, a multilayer board can also be manufactured by combining the prepreg of the present invention and the printed wiring board for inner layer and laminating molding.

[printed wiring board]

The printed wiring board of the present invention contains the prepreg of the present invention or the laminated board of the present invention.

The printed wiring board of the present invention can be manufactured, for example, by subjecting the metal foil of the laminated board of the present invention to circuit processing. Circuit processing, for example, after forming a resist pattern on the surface of a metal foil, removing unnecessary portions of the metal foil by etching, peeling off the resist pattern, forming a necessary through hole with a drill or laser, and forming a resist pattern again After that, plating for making the through hole electrically conductive may be performed, and finally, the resist pattern may be peeled off.

The above-described metal clad laminate is further laminated on the surface of the printed wiring board obtained in this way under the same conditions as described above, and circuit processing is performed in the same manner as above to obtain a multilayer printed wiring board. In this case, it is not always necessary to form a through hole, and a via hole may be formed, or both may be formed. Such multi-layering may be performed on the required number of sheets.

[Semiconductor Package]

The semiconductor package of the present invention is made using the printed wiring board of the present invention.

The semiconductor package of the present invention can be manufactured by mounting a semiconductor chip, memory, or the like at a predetermined position on the printed wiring board of the present invention.

Example

Next, the present invention will be described in more detail by the following examples, but these examples do not limit the present invention in any sense. The performance of the prepregs and the like obtained in each case was evaluated based on the following evaluation method. In addition, room temperature in this Example is 25 degreeC.

[Assessment Methods]

<1. Formability>

With respect to the evaluation board obtained by immersing the 4-layer copper-clad laminate produced in each case in etchant and removing the outer layer copper, the presence or absence of voids and scratches in the inside surface of 340 mm × 500 mm was visually confirmed. A case in which voids and scratches were not confirmed was regarded as "no abnormality", and a case in which voids or scratches were confirmed was regarded as "abnormality", and were used as an index of moldability.

<2. Fluctuation of the amount of dimensional change>

In the surface of the double-sided copper-clad laminate produced in each case, as shown in FIG. 1, a hole having a diameter of 1.0 mm was perforated, and an evaluation board shown in the schematic diagram of FIG. 1 was obtained.

1, the distance between holes in the "warp direction" (between 1-7, between 2-6 and between 3-5) at three points, and the distance between holes in the "weft direction" (between 1-3 and 8 Between -4 and between 7 and 5) three points were measured using "QV-A808P1L-D" (manufactured by Mitutoyo Co., Ltd.), and each measurement distance was set as an initial value. Subsequently, the evaluation substrate was immersed in an etching solution to remove the outer copper foil, and then heated in a dryer at 185° C. for 60 minutes. After cooling, the distance between each hole was measured by the same method as the initial value, and it was set as the measured value after heat treatment.

For the distance between each hole, the rate of change of the measured value after heat treatment with respect to the initial value ((initial value - measured value after heat treatment) × 100 / (initial value)) is obtained, and the standard deviation σ for their average value is calculated , and the corresponding standard deviation σ was taken as the variation of the amount of dimensional change.

Example 1

(Production of prepreg precursor: steps 1 to 2)

(A) 19 parts by mass of a biphenylaralkyl novolak-type epoxy resin (epoxy equivalent: 280 to 300 g/eq) as a thermosetting resin;

(B) 16 parts by mass of cresol novolac resin (hydroxyl equivalent: 119 g/eq) as a curing agent;

(C) 0.02 parts by mass of 2-ethyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd.) as a curing accelerator;

(D) As an inorganic filler, 65 parts by mass of spherical silica (average particle diameter: 2 μm) was mixed and diluted with a solvent (methyl ethyl ketone) to prepare a varnish-like thermosetting resin composition (solid content concentration: 70 mass%).

This thermosetting resin composition is impregnated into a glass cloth (manufactured by Nitto Boseki Co., Ltd., trade name: 1037 cloth, thickness: 0.025 mm) as a substrate, and then at 100 to 200 ° C. until the thermosetting resin composition is B-staged. It was placed in a drying furnace and heated for 5 to 15 minutes. Thereafter, it was cooled to room temperature by natural cooling to obtain a prepreg precursor.

(Prepreg production: process 3)

With respect to the prepreg precursor obtained above, a surface heating treatment was performed using a panel heater at a heating set temperature of 500 ° C. under conditions of a heating time of 3 seconds so that the surface temperature of the prepreg precursor reached 70 ° C., and cooled to room temperature prepreg was obtained.

In addition, content of the solid content conversion of the thermosetting resin composition in the obtained prepreg was 70 mass %.

(Production of copper clad laminate)

Using one sheet of the prepreg obtained above, 18 μm copper foil “YGP-18” (manufactured by Nippon Denkai Co., Ltd.) was overlapped on both sides, and at a temperature of 190 ° C. and a pressure of 25 kgf / cm ² (2.45 MPa), 90 Heat-pressing molding was performed for a minute to produce a double-sided copper clad laminate for one sheet of prepreg.

Inner layer adhesion treatment (using “BF treatment liquid” (manufactured by Hitachi Chemical Co., Ltd.)) was performed on both copper foil surfaces of the obtained double-sided copper-clad laminate, and prepregs were overlapped one by one to form 18 μm copper foil “YGP- 18” (manufactured by Nippon Denkai Co., Ltd.) were stacked, and heat press molding was carried out at a temperature of 190° C. and a pressure of 25 kgf/cm ² (2.45 MPa) for 90 minutes to prepare a four-layer copper-clad laminate.

On the other hand, 18 μm copper foil “3EC-VLP-18” (manufactured by Mitsui Kinzoku Co., Ltd.) was superimposed on both sides of one sheet of prepreg, and heated for 90 minutes at a temperature of 190 ° C. and a pressure of 25 kgf / cm ² (2.45 MPa) Press molding was performed to produce a double-sided copper-clad laminate for one sheet of prepreg.

Example 2

(Production of prepreg precursor: steps 1 to 2)

Component (A): A solution of the maleimide compound (A) prepared in Preparation Example 1 below was used.

[Production Example 1]

19.2 g of 4,4'-diaminodiphenylmethane, 174.0 g of bis(4-maleimidephenyl)methane, and p-aminophenol were placed in a reaction vessel having a volume of 1 L equipped with a thermometer, a stirrer and a water meter equipped with a reflux condenser. 6.6 g and 330.0 g of dimethylacetamide were added and reacted at 100° C. for 2 hours to obtain a dimethylacetamide solution of maleimide compound (A) (Mw = 1,370) having an acidic substituent and an N-substituted maleimide group, (A ) was used as a component.

In addition, the said weight average molecular weight (Mw) was converted from the calibration curve using standard polystyrene by gel permeation chromatography (GPC). Calibration curve is standard polystyrene: TSKstandard POLYSTYRENE (Type; A-2500, A-5000, F-1, F-2, F-4, F-10, F-20, F-40) [manufactured by Tosoh Corporation] It was approximated by a cubic equation using The conditions of GPC are shown below.

Apparatus: (Pump: L-6200 type [manufactured by Hitachi High Technologies Co., Ltd.]),

(Detector: L-3300 type RI [manufactured by Hitachi High Technologies Co., Ltd.]),

(Column Oven: L-655A-52 [manufactured by Hitachi High Technologies Co., Ltd.])

column; TSKgel SuperHZ2000+TSKgel SuperHZ2300 (all manufactured by Tosoh Corporation)

Column size: 6.0 mm × 40 mm (guard column), 7.8 mm × 300 mm (column)

Eluent: tetrahydrofuran

Sample concentration: 20mg/5mL

Injection volume: 10 μL

Flow rate: 0.5 mL/min

Measurement temperature: 40℃

(A) as a thermosetting resin, 45 parts by mass of the maleimide compound (A) obtained above and 30 parts by mass of a cresol novolak-type epoxy resin;

As component (B), 2 parts by mass of dicyandiamide (manufactured by Nippon Carbide Kogyo Co., Ltd.),

As component (D), 50 parts by mass of fused silica (average particle size: 1.9 µm, specific surface area: 5.8 m ² /g) treated with an aminosilane coupling agent;

As a thermoplastic resin, 25 parts by mass of a copolymer resin of styrene and maleic anhydride (styrene/maleic anhydride = 4, Mw = 11,000);

As a flame retardant, 2.0 parts by mass of an aromatic phosphate ester in terms of phosphorus atoms

(However, in the case of a solution, the amount in terms of solid content is shown.), and methyl ethyl ketone is added so that the solid content concentration of the solution is 65 to 75% by mass to prepare a resin varnish.

Each obtained resin varnish was impregnated with a glass cloth (0.1 mm) of IPC standard #3313, dried for 4 minutes on a panel heater set at 160°C (step 1), and then left to cool to room temperature (step 2) to prepare a prepreg. precursor was obtained.

(Prepreg production: process 3)

The prepreg precursor obtained above is subjected to surface heating treatment using a panel heater at a heating set temperature of 500 ° C. under conditions of a heating time of 3 seconds so that the surface temperature of the prepreg precursor reaches 70 ° C., and cooled to room temperature prepreg was obtained.

In addition, content of the solid content conversion of the thermosetting resin composition in the obtained prepreg was 70 mass %.

(Production of copper clad laminate)

A four-layer copper-clad laminate and a double-sided copper-clad laminate were produced in the same manner as in Example 1 using one sheet of the prepreg obtained above.

[Comparative Example 1]

In Example 1, a prepreg, a 4-layer copper clad laminate, and a double-sided copper clad laminate were produced in the same manner as in Example 1, except that Step 3 was not performed.

[Comparative Example 2]

In Example 2, a prepreg, a 4-layer copper clad laminate, and a double-sided copper clad laminate were produced in the same manner as in Example 1, except that Step 3 was not performed.

Table 1 shows the evaluation results of the four-layer copper-clad laminate and the double-sided copper-clad laminate obtained in each of the above examples.

The prepregs of Examples 1 and 2 had good resin embedding properties in formability, and no abnormalities such as scratches and voids were observed on the laminates obtained from these prepregs. In addition, the prepregs of Examples 1 and 2 tended to have smaller fluctuations in the amount of dimensional change (standard deviation (σ)) compared to the prepregs of Comparative Examples 1 and 2 that were not subjected to surface heat treatment.

The prepreg of the present invention is excellent in moldability and has little variation in dimensional change, so it is useful for highly integrated semiconductor packages, printed wiring boards for electronic devices, and the like.

Claims (10)

A prepreg manufacturing method comprising the following steps 1 to 3.
Step 1: This is a step of obtaining a prepreg precursor. The prepreg precursor is obtained by B-staging a thermosetting resin composition, and the B-staging is performed by impregnating a base material with the thermosetting resin composition and then performing heat treatment. .
Process 2: A process of cooling the prepreg precursor obtained in Process 1.
Step 3: This is a step of obtaining a prepreg. The prepreg is obtained by subjecting the prepreg precursor cooled in step 2 to a surface heating treatment without hot pressing treatment, and the surface heating treatment increases the surface temperature of the prepreg precursor. It is a process of elevating The prepreg manufacturing method according to claim 1, wherein the surface heating treatment in Step 3 is a treatment for raising the surface temperature of the prepreg precursor by 5 to 110°C. The prepreg manufacturing method according to claim 1 or 2, wherein the surface heating treatment in step 3 is a treatment for heating the surface temperature of the prepreg precursor to 20 to 130°C. The prepreg manufacturing method according to claim 1 or 2, wherein the surface heating treatment in step 3 is a treatment of heating the prepreg precursor in an environment of 200 to 700°C. The prepreg manufacturing method according to claim 4, wherein the surface heating treatment in step 3 is a treatment of heating the prepreg precursor in an environment of 350 to 700°C. The prepreg manufacturing method according to claim 1 or 2, wherein the heating time of the surface heat treatment in step 3 is 1.0 to 10.0 seconds. The prepreg manufacturing method according to claim 1 or 2, wherein the substrate is a glass cloth. A method for producing a laminated sheet in which a prepreg manufactured according to the prepreg manufacturing method according to claim 1 or 2 and metal foil are laminated and molded. A prepreg manufactured according to the prepreg manufacturing method according to claim 1 or 2, or
Laminate manufactured according to the manufacturing method of a laminated plate in which the prepreg manufactured according to the prepreg manufacturing method according to claim 1 or 2 and the metal foil are laminated and molded.
Method for manufacturing a printed wiring board using A method for manufacturing a semiconductor package using a printed wiring board manufactured according to the method for manufacturing a printed wiring board according to claim 9.

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