JP5740941B2 - Prepreg, metal-clad laminate, printed wiring board, and semiconductor device - Google Patents

Description

  The present invention relates to a resin varnish, a prepreg, a metal-clad laminate, a printed wiring board, and a semiconductor device.

  In the electronic materials field, along with demands for downsizing and speeding up electronic devices including information processing devices such as notebook personal computers and mobile phones, electronic components such as semiconductor devices used in such electronic devices are also downsized. As the speed increases, the degradation of electrical signals is a problem in high-speed information transmission. Electrical signal degradation is expressed as the sum of conductor loss and dielectric loss. In particular, dielectric loss due to the dielectric properties of the interlayer insulation material used in multilayer printed wiring boards is limited in the high-frequency region required for high-speed transmission. Increase significantly. For this reason, dielectric loss is a major cause of electrical signal degradation at frequencies in the GHz band. In order to solve this problem, it is required to use a material having low dielectric constant and low dielectric loss tangent for the insulating layer of the printed wiring board.

The insulating layer of the printed wiring board can be formed using a prepreg. In general, a prepreg is obtained by containing a resin composition mainly composed of a thermosetting resin such as an epoxy resin in a solvent to form a resin varnish, impregnating it into a substrate such as a glass cloth, and drying by heating. Produced. As a means for reducing the dielectric constant and the dielectric loss tangent of the insulating layer of the printed wiring board, there is a method of increasing the amount of the resin composition held on the glass cloth of the prepreg used for the insulating layer. Especially in the high-frequency region in the GHz band, glass cloth has a relatively high dielectric constant and dielectric loss tangent, and resin has a relatively low dielectric constant and dielectric loss tangent. By increasing the volume ratio of the resin composition, the dielectric constant and dielectric loss tangent of the entire prepreg can be lowered.
Moreover, the printed wiring board produced by providing a conductor layer such as a metal foil on the prepreg to form a conductor circuit layer has a relatively high dielectric constant and dielectric loss tangent by increasing the amount of the resin composition of the prepreg. Since the distance from the high glass cloth to the conductor circuit layer becomes wide, it is possible to reduce the dielectric constant and the dielectric loss tangent.
However, if the amount of the resin composition of the prepreg is increased, the prepreg becomes thicker, so that the amount of the resin composition of the prepreg is increased, and the thickness of the prepreg is maintained to be equal to that of the conventional or thinner than that of the conventional. Requires the use of a thin glass cloth.
However, a prepreg produced using a thin glass cloth has a large amount of resin composition with respect to the glass cloth, but since the influence of the elastic modulus and thermal expansion coefficient of the resin is large, the elastic modulus of the entire prepreg is decreased and the thermal expansion coefficient is increased. Occur. Therefore, conventionally, a decrease in the elastic modulus and an increase in the thermal expansion coefficient of the prepreg have been prevented by increasing the content of the filler in the resin composition. Further, since the filler has a lower dielectric loss tangent than the resin, the dielectric loss tangent of the prepreg can be further reduced by containing a large amount of the filler in the resin composition.

  Patent Document 1 discloses a glass cloth having a thickness change rate of 10% or more after performing a raising process for cutting a monofilament constituting a yarn, and a semi-cured curable resin held by the glass cloth. There is disclosed a prepreg characterized in that the prepreg has a low dielectric constant and a low dielectric loss tangent because the retention rate of the semi-cured curable resin is increased by raising the glass cloth.

JP-A-8-41224

  However, when the amount of the filler in the resin composition is increased, the prepreg produced using the resin composition has poor adhesion to the conductor layer when used as a core substrate substrate, or the prepreg is used for build-up. When used as an insulating material, problems such as difficulty in embedding circuits arise. In addition, in a prepreg with a large amount of filler, voids are likely to occur in a semi-cured resin layer, and printed wiring boards and semiconductor devices obtained using the prepreg have insulation reliability due to voids generated in the insulating layer. Is likely to occur. Such a problem can be improved by using a low-viscosity resin with low reactivity, but the varnish of the resin composition using the low-viscosity resin has high fluidity, and the resin in the varnish Easy to separate from filler. Therefore, when a prepreg is produced using the varnish, and the resulting prepreg is heated and pressed to produce a laminate, the resin and the filler are separated when the varnish is impregnated into the substrate. As a result, the resulting laminate tends to have poor appearance such as streak-like unevenness.

  In addition, the prepreg disclosed in Patent Document 1 uses a brushed glass cloth according to the experiments of the present inventor. Therefore, in order to obtain a laminated board having a high smoothness of the circuit pattern on the surface, The thickness becomes thick and it is difficult to cope with the thinning.

The present invention has been made to solve the above-described problems, and the object of the present invention is to provide excellent dielectric properties, adhesion to a conductor layer, and adhesion to a non-smooth surface subjected to circuit processing ( An object of the present invention is to provide a resin varnish that is excellent in circuit embedding property, does not generate voids, and can produce an insulating layer having no appearance defects such as streaky irregularities.
Another object of the present invention is to obtain excellent dielectric properties, adhesion to a conductor layer and circuit embedding obtained by holding the resin varnish on a glass cloth and then removing the ketone solvent. The object is to provide a prepreg which is excellent and free from voids.
Still another object of the present invention is to provide a metal-clad laminate produced using the prepreg, provide a printed wiring board using the prepreg or the metal-clad laminate, and produce using the printed wiring board. An object of the present invention is to provide a semiconductor device.

The above object is achieved by the following inventions (1) to ( 6 ).

(1) A ketone solvent contains a thermosetting resin composition containing a thermosetting resin containing an epoxy resin and a bismaleimide compound and a filler contained in a solid content of 60 to 85% by mass. Obtained by removing the ketone solvent after holding the resin varnish on a glass cloth,
The weight per unit area of glass cloth with ^{24g / m 2 ~49g / m 2} , and the weight per unit area of the thermosetting resin composition is a ^{48g / m 2 ~279g / m 2} ,
Weight per unit area of the thermosetting resin composition, are two-fold ～5.7 Baidea the weight per unit area of the glass cloth,
The prepreg characterized in that the ketone solvent contains at least one of cyclohexanone, isophorone and methylcyclohexanone, and the total content of cyclohexanone, isophorone and methylcyclohexanone is 70% by mass or more .
(2 ) The prepreg according to (1 ) above, wherein the thermosetting resin further contains a cyanate resin.
( 3 ) A metal-clad laminate obtained by laminating a metal foil on the prepreg according to the above (1) or (2) and heating and pressing.
( 4 ) A printed wiring board comprising the metal-clad laminate as described in ( 3 ) above as an inner circuit board.
( 5 ) A printed wiring board comprising the prepreg described in (1) or (2) above as an insulating layer on an inner layer circuit.
( 6 ) A semiconductor device, wherein a semiconductor element is mounted on the printed wiring board according to ( 4 ) or ( 5 ).

According to the present invention, a resin varnish that can produce an insulating layer having excellent dielectric properties, excellent adhesion to a conductor layer and excellent circuit embedding properties, no generation of voids, and no appearance defects such as streaky irregularities. Can be obtained.
Further, according to the present invention, it is possible to obtain a prepreg having excellent dielectric characteristics, excellent adhesion to a conductor layer and circuit embedding property, and no generation of voids, using the resin varnish.
Furthermore, according to the present invention, a metal-clad laminate can be obtained using the prepreg, a printed wiring board can be obtained using the prepreg or the metal-clad laminate, and the printed wiring board is used. Thus, a semiconductor device can be obtained.

It is the schematic which shows an example of the impregnation coating equipment used for manufacture of the prepreg of this invention.

(Resin varnish)
The resin varnish of the present invention is a thermosetting resin composition (hereinafter simply referred to as a thermosetting resin composition containing a thermosetting resin containing an epoxy resin and a bismaleimide compound and a filler contained in a solid content of 60 to 85% by mass. It may be referred to as “resin composition”) in a ketone solvent.
In addition, in this invention, a thermosetting resin composition means all components other than the solvent of a resin varnish, ie, solid content, and a liquid resin component etc. are contained in solid content.
In the present invention, the term “containing a thermosetting resin composition in a solvent” means that a soluble resin or the like contained in the thermosetting resin composition is dissolved in a solvent, and an insoluble filler or the like is dispersed in the solvent. Means that.

If the resin varnish obtained by containing the resin composition in a solvent has too high fluidity, the resin and the filler are easily separated. Therefore, the prepreg obtained by holding the resin varnish on the glass cloth and then removing the solvent is heated due to separation of the resin and the filler when the resin varnish is impregnated into the base material. When pressure forming, streaky unevenness occurs. On the other hand, when a conventional resin varnish with low fluidity is used, even if the obtained prepreg is heat-press molded, streaky unevenness does not occur. However, a prepreg obtained using a resin varnish with low fluidity has poor adhesion to a conductor layer when used as a base material for a core substrate, or it becomes difficult to embed a circuit when used as a build-up insulating material. Or Furthermore, if a resin varnish with low fluidity is used, voids are likely to occur in the resin layer when the resulting prepreg and the prepreg are heated and pressed, and insulation of printed wiring boards and semiconductor devices manufactured using the prepreg Reducing reliability. Therefore, the resin varnish used for preparing the prepreg has a fluidity that is not too high that the resin and the filler are difficult to separate in the state of the resin varnish containing the solvent, and is obtained using the resin varnish. The prepreg to be formed is required to have a composition that is excellent in adhesion to a conductor layer when used as a core substrate base material and excellent in circuit embedding when used as a build-up insulating material and does not generate voids.
As a result of intensive studies, the present inventors have combined a bismaleimide compound and a ketone solvent, so that the resin and the filler are contained in the solvent-containing state even though it contains a large amount of the filler. When the prepreg obtained by using the resin varnish has a fluidity that is not difficult to separate and is used as a base material for a core substrate, and when used as an insulating material for buildup It has been found that it is excellent in circuit embedding, does not generate voids, and does not cause streak-like unevenness when heated and pressed.
Since bismaleimide compounds are highly polar, they do not dissolve in solvents with low polarity, and because the double bond portion of bismaleimide compounds has Lewis acid properties, it dissolves in protic polar solvents such as alcohol. do not do. Bismaleimide compounds dissolve in nitrogen-containing aprotic polar solvents such as N, N-dimethylformamide and N, N-dimethylacetamide, but when dissolved in these solvents, bismaleimide compounds and nitrogen-containing compounds are dissolved. The interaction of the aprotic polar solvent is strong and the fluidity becomes high. In contrast, the present inventors have found that when a ketone compound is used as a solvent, the bismaleimide compound is dissolved and the fluidity of the varnish is lowered. This is because the Lewis acid nature of the double bond part of the bismaleimide compound and the carbonyl part of the ketone solvent interact and dissolve appropriately, but the hydrophobic alkyl chain part of the ketone solvent moderately It is considered that the fluidity of the varnish decreases due to repulsion. In addition, the present inventors have found that among ketone solvents, cyclic ketones such as cyclohexanone, methylcyclohexanone, and isophorone have high carbonyl group polarity, and can achieve both high varnish solubility and low fluidity. It was. In addition, the bismaleimide compound and the ketone solvent in the resin varnish of the present invention interact with each other in an equilibrium state, and a part of the bismaleimide compound hardly undergoes a curing reaction. Some of the bismaleimide compounds that have become difficult to cure are present even after the resin varnish is heated and dried, and slows the progress of the curing reaction of the resin composition, so the viscosity of the resin composition in a semi-cured state It is thought that lowers. Therefore, the prepreg obtained by using the resin varnish of the present invention contains a large amount of filler in the resin composition, but the adhesion with the conductor layer when used as a core substrate substrate, And it is excellent in circuit embedding when used as an insulating material for buildup, and no void is generated.
Furthermore, the prepreg obtained by using the resin varnish of the present invention has excellent adhesiveness to the conductor layer because the resin varnish of the present invention contains an epoxy resin, and includes a bismaleimide compound. The dielectric loss tangent is excellent, and by containing a large amount of filler, it has high elasticity and low thermal expansion, and the dielectric loss tangent is lower.

First, the thermosetting resin composition used for the resin varnish of the present invention will be described.
The thermosetting resin composition contains at least a thermosetting resin containing an epoxy resin and a bismaleimide compound, and a filler.

The thermosetting resin includes at least an epoxy resin and a bismaleimide compound, and is not particularly limited. For example, cyanate resin, phenol resin, benzoxazine resin, urea resin, melamine resin, silicon resin, polyester resin, etc. May be included.
The thermosetting resin contains an epoxy resin from the viewpoint of curability and adhesion to the conductor layer, and contains a bismaleimide compound from the viewpoint of curability and dielectric properties (low dielectric constant, low dielectric loss tangent). Further, the bismaleimide compound has an effect of lowering the fluidity of the resin varnish by combining with a ketone solvent contained in the resin varnish of the present invention. In addition, the thermosetting resin improves flame retardancy, reduces the thermal expansion coefficient, improves the prepreg dielectric properties (low dielectric constant, low dielectric loss tangent), adhesion to the conductor layer, etc. In view of improving heat resistance, rigidity and the like, it is more preferable to include a cyanate resin.

The epoxy resin is not particularly limited, but is an epoxy resin that does not substantially contain a halogen atom. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, Bisphenol Z type epoxy resin (4,4′-cyclohexyldiene bisphenol type epoxy resin), bisphenol P type epoxy resin (4,4 ′-(1,4-phenylenediisopridiene) bisphenol type epoxy resin), bisphenol M Type epoxy resins (4,4 '-(1,3-phenylenediisopridiene) bisphenol type epoxy resins) and other bisphenol type epoxy resins, phenol novolac type epoxy resins, and cresol novolak type epoxy resins. Si resin, biphenyl type epoxy resin, xylylene type epoxy resin, phenol aralkyl type epoxy resin, biphenyl aralkyl type epoxy resin, biphenyl dimethylene type epoxy resin, trisphenol methane novolak type epoxy resin, 1,1,2,2- (tetra Phenol) ethane glycidyl ethers, trifunctional or tetrafunctional glycidyl amines, arylalkylene type epoxy resins such as tetramethylbiphenyl type epoxy resins, naphthalene skeleton modified cresol novolak type epoxy resins, methoxynaphthalene modified cresol novolak type epoxy resins , Naphthalene type epoxy resins such as methoxynaphthalene dimethylene type epoxy resin, naphthol alkylene type epoxy resin, anthracene type epoxy resin, phenoxy type epoxy Fat, dicyclopentadiene type epoxy resins, norbornene type epoxy resins, adamantane type epoxy resins, fluorene type epoxy resins, flame-retarded epoxy resin or the like halogenated epoxy resins. One of these can be used alone, two or more having different molecular weights can be used in combination, and one or two or more thereof and their prepolymers can be used in combination.
Among these epoxy resins, in particular, from the group consisting of biphenylaralkyl type epoxy resins, naphthalene skeleton modified cresol novolac type epoxy resins, anthracene type epoxy resins, dicyclopentadiene type epoxy resins, cresol novolac type epoxy resins, and naphthalene type epoxy resins. At least one selected is preferred. Thereby, a low water absorption, heat resistance, and a flame retardance improve.

  Although the molecular weight of the said epoxy resin is not specifically limited, 300-3000 are preferable and 400-2000 are especially preferable. If the molecular weight is less than the lower limit, the mechanical strength of the prepreg may be lowered or tackiness may occur. When the molecular weight exceeds the above upper limit, the impregnation property into the glass cloth at the time of prepreg production is lowered, and a uniform product may not be obtained, or the curing reaction is accelerated, and the conductor layer in the semi-cured state is Adhesion and circuit embedding may be deteriorated.

  Although content of the said epoxy resin is not specifically limited, 5-25 weight% is preferable on the solid content basis of the whole thermosetting resin composition, and 6-10 weight% is especially preferable. If the content is less than the lower limit, the curability may decrease, the moisture resistance of the resulting product may decrease, or the adhesion to the conductor layer may decrease. In some cases, the performance may be reduced, or the dielectric characteristics may be insufficient.

  The bismaleimide compound is a compound having maleimide groups at both ends of a molecular chain, and for example, a compound represented by the following formula (1) can be used. However, the bismaleimide compound may have a maleimide group in addition to both ends of the molecular chain.

In formula (1), R ^{1 to} R ⁴ are hydrogen or a substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms, and R ⁵ is a divalent substituted or unsubstituted organic group. Here, the organic group is a hydrocarbon group that may contain a heteroatom, and examples of the heteroatom include O and S. R ⁵ preferably has a main chain structure in which a methylene group, an aromatic ring and an ether bond (—O—) are bonded in any order, and may have a substituent and / or a side chain on the main chain. It is a good hydrocarbon group, and the total number of methylene groups, aromatic rings and ether bonds contained in the main chain structure is 15 or less, more preferably 11 or less. Examples of the substituent or side chain include a hydrocarbon group having 3 or less carbon atoms, a maleimide group, and an alkoxy group.

  Specific examples of preferred bismaleimide compounds (2) to (5) according to the present invention are shown below, but the present invention is not limited to these compounds.

Specific examples of the bismaleimide compound include 4,4′-diphenylmethane bismaleimide, m-phenylene bismaleimide, p-phenylene bismaleimide, and 2,2′-bis [4- (4-maleimidophenoxy) phenyl]. Propane, bis- (3-ethyl-5-methyl-4-maleimidophenyl) methane, 4-methyl-1,3-phenylenebismaleimide, N, N′-ethylenedimaleimide, N, N′-hexamethylenedimaleimide Etc. Among these, in consideration of low water absorption, 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane and bis- (3-ethyl-5-methyl-4-maleimidophenyl) methane are preferable. .
The bismaleimide compounds may be used singly, or different types of bismaleimide compounds may be used in combination, or a bismaleimide compound and a prepolymer thereof may be used in combination.

  Although content of the said bismaleimide compound is not specifically limited, 5 to 25 weight% is preferable on the solid content basis except the solvent from the whole resin varnish, and 6 to 10 weight% is especially preferable. If the content is less than the lower limit, curability and dielectric properties (low dielectric constant, low dielectric loss tangent) may be insufficient, and if the content exceeds the upper limit, solder heat resistance may deteriorate.

  The cyanate resin is not particularly limited, and can be obtained, for example, by reacting a halogenated cyanide compound with phenols or naphthols, and prepolymerizing by a method such as heating as necessary. Moreover, the commercial item prepared in this way can also be used.

  The kind of the cyanate resin is not particularly limited. For example, bisphenol cyanate resin such as novolak type cyanate resin, bisphenol A type cyanate resin, bisphenol E type cyanate resin, tetramethylbisphenol F type cyanate resin, and naphthol aralkyl type. And cyanate resin. The novolac-type cyanate resin can reduce the thermal expansion coefficient of the resin layer, and is excellent in the mechanical strength and dielectric properties (low dielectric constant, low dielectric loss tangent) of the resin layer.

  The cyanate resin preferably has two or more cyanate groups (—O—CN) in the molecule. For example, 2,2′-bis (4-cyanatophenyl) isopropylidene, 1,1′-bis (4-cyanatophenyl) ethane, bis (4-cyanato-3,5-dimethylphenyl) methane, 3-bis (4-cyanatophenyl-1- (1-methylethylidene)) benzene, dicyclopentadiene type cyanate ester, phenol novolac type cyanate ester, bis (4-cyanatophenyl) thioether, bis (4-cyanato) Phenyl) ether, 1,1,1-tris (4-cyanatophenyl) ethane, tris (4-cyanatophenyl) phosphite, bis (4-cyanatophenyl) sulfone, 2,2-bis (4-si Anatophenyl) propane, 1,3-, 1,4-, 1,6-, 1,8-, 2,6- or 2,7-dicyanatonaphthalene, 1 Cyanate resin obtained by reaction of 3,6-tricyanatonaphthalene, 4,4-dicyanatobiphenyl, phenol novolac type, cresol novolac type polyhydric phenols with cyanogen halide, naphthol aralkyl type polyvalent naphthol And cyanate resin obtained by the reaction of a halogenated cyanide. Among these, phenol novolac-type cyanate resin is excellent in flame retardancy and low thermal expansion, and 2,2-bis (4-cyanatophenyl) isopropylidene and dicyclopentadiene-type cyanate ester are used to control the crosslinking density, Excellent moisture resistance reliability. In particular, a phenol novolac type cyanate resin is preferred from the viewpoint of low thermal expansion. Furthermore, other cyanate resins may be used alone or in combination of two or more, and are not particularly limited.

The said cyanate resin may be used independently, can also use together cyanate resin from which a kind differs, or can also use cyanate resin and its prepolymer together.
The prepolymer is usually obtained by, for example, trimerizing the cyanate resin by a heating reaction or the like, and is preferably used for adjusting the moldability and fluidity of the varnish.
The prepolymer is not particularly limited. For example, when a prepolymer having a trimerization rate of 20 to 50% by weight is used, good moldability and fluidity can be expressed.

The weight average molecular weight of the cyanate resin is not particularly limited, but is preferably 5.0 × 10 ^{2 to} 4.5 × 10 ³ , and particularly preferably 6.0 × 10 ^{2 to} 3.0 × 10 ³ . If the weight average molecular weight is less than the lower limit, tackiness may occur when the prepreg is produced, and the prepreg may adhere to each other or transfer of the resin may occur. Further, when the weight average molecular weight exceeds the upper limit, the reaction becomes too fast, and in particular, the prepreg may be inferior in adhesion to the conductor layer and circuit embedding property. In addition, the weight average molecular weight of cyanate resin is the value measured by the gel permeation chromatography method of polystyrene conversion.

  Although content of the said cyanate resin is not specifically limited, 5 to 25 weight% is preferable on the solid content basis of the whole thermosetting resin composition, and 6 to 10 weight% is especially preferable. When the content is within the above range, the cyanate resin can effectively exhibit heat resistance and flame retardancy. Further, if the content is less than the lower limit, the thermal expansibility increases and the heat resistance may decrease, and if it exceeds the upper limit, the strength of the prepreg obtained may decrease.

  In addition to the thermosetting resin, the thermosetting resin composition used in the present invention contains a thermoplastic resin such as a phenoxy resin, a polyimide resin, a polyamideimide resin, a polyphenylene oxide resin, and a polyethersulfone resin. May be.

The thermosetting resin composition used in the present invention contains a filler. As a result, the fluidity of the resin varnish containing the thermosetting resin composition in the solvent can be reduced, and the prepreg produced using the resin varnish can have high elasticity, low thermal expansion, and low dielectric loss tangent. It can be.
Examples of the filler include silicates such as talc, fired clay, unfired clay, mica, and glass; oxides such as titanium oxide, alumina, silica, and fused silica; calcium carbonate, magnesium carbonate, hydrotalcite, and the like. Carbonates: hydroxides such as aluminum hydroxide, magnesium hydroxide, calcium hydroxide, sulfates or sulfites such as barium sulfate, calcium sulfate, calcium sulfite; zinc borate, barium metaborate, aluminum borate, boron Borates such as calcium oxide and sodium borate, nitrides such as aluminum nitride, boron nitride, silicon nitride and carbon nitride; inorganic fillers such as titanates such as strontium titanate and barium titanate, silicon rubber, acrylic Organic fillers such as rubber particles and polystyrene powder can be used

Of these, silica is preferred as the filler used in the present invention, and fused silica is particularly preferred because of its low dielectric loss tangent and low thermal expansion.
In addition, the shape of the filler includes a crushed shape, a spherical shape, and the like, but in order to ensure the impregnating property of the resin composition to the glass cloth in the prepreg production, the spherical shape is preferable, and in particular, spherical silica is used. preferable.

  The particle size of the filler is not particularly limited, but the average particle size is preferably 0.01 to 5.0 μm, particularly preferably 0.1 to 2.0 μm. When the average particle size of the filler is less than the lower limit, when preparing a resin varnish using the resin composition of the present invention, the viscosity of the resin varnish becomes high, so that the workability when preparing a prepreg is improved. May have an effect. On the other hand, if the upper limit is exceeded, phenomena such as sedimentation of the filler may occur in the resin varnish. By making the average particle diameter of the filler within the above range, the workability can be improved. The average particle diameter can be measured by, for example, an ultrasonic vibration current method (zeta potential), ultrasonic attenuation spectroscopy (particle size distribution), and laser diffraction scattering method. Specifically, the average particle diameter of the fine particles can be defined by D50.

Further, the filler is not particularly limited, but a filler having a monodispersed average particle diameter can be used, and a filler having a polydispersed average particle diameter can be used. In the present invention, the average particle size being monodispersed means that the standard deviation of the particle size is 10% or less, and being polydispersed means that the standard deviation of the particle size is 10% or more. Means things.
As the filler used in the present invention, a monodisperse and / or polydisperse filler having an average particle diameter can be used alone or in combination of two or more.

  Although content of the said filler is not specifically limited, 60 to 85 weight% is preferable on the solid content basis of the said whole thermosetting resin composition, and 65 to 75 weight% is especially preferable. When the content is in the above range, the dispersibility of the filler is excellent, and the resin varnish is easily held by the glass cloth, so that the resin layer can be thickened to the glass cloth, and further, the thermosetting resin composition is used. The prepreg produced in this way has high elasticity, low thermal expansion, low dielectric constant, and low dielectric loss tangent.

The thermosetting resin composition used in the present invention can contain a curing agent.
The curing agent can be used without particular limitation as long as it cures an epoxy resin. Known curing agents for epoxy resins include aliphatic amines, aromatic amines, dicyandiamide, dicarboxylic acid dihydrazide compounds, and acid anhydrides. Products, phenol resins and the like can be used. These curing agents may be used alone or in combination of two or more. Among these, aromatic amines are preferable from the viewpoint of heat resistance.

The content of the curing agent is not particularly limited, but when a cyanate resin is not used as the thermosetting resin, it is preferably 2 to 15% by weight based on the solid content of the entire thermosetting resin composition, particularly 5 ˜12% by weight is preferred. If the content is less than the lower limit, the effect of accelerating curing is insufficient and the fluidity of the resin composition is high, streaky unevenness occurs during heat-press molding of the prepreg, or curing is insufficient. The monomer may remain, and as a result, solder heat resistance may deteriorate. On the other hand, if the content exceeds the upper limit, the effect of promoting curing may be saturated, reactive groups that do not contribute to curing may remain, and dielectric characteristics (low dielectric constant, low dielectric loss tangent) may deteriorate. is there.
In addition, since cyanate resin and an amino group react violently when using cyanate resin as the said thermosetting resin, content of the said hardening | curing agent is 0-5 weight on the solid content basis of the said whole thermosetting resin composition. % Is preferable, and 0 to 2% by weight is particularly preferable.

  In the present invention, a curing agent and a curing accelerator may be used in combination. Although it does not specifically limit as said hardening accelerator, For example, organic phosphorus type | system | groups, such as a triphenyl phosphine and a tetraphenyl phosphonium tetraphenyl borate, 1.8-diazabicycloundecene, a triethylenediamine, 2-ethyl-4- Nitrogen-based curing accelerators such as methylimidazole and 1-benzyl-2-phenylimidazole or their adducts are preferably used.

  Moreover, although the thermosetting resin composition used for this invention is not specifically limited, A coupling agent can be used. This improves the wettability of the interface between the thermosetting resin and the filler, thereby uniformly fixing the resin and the filler to the glass cloth and improving the heat resistance, particularly the solder heat resistance after moisture absorption. be able to.

  Although it does not specifically limit as said coupling agent, For example, an epoxy silane coupling agent, a cationic silane coupling agent, an aminosilane coupling agent, a titanate coupling agent, a silicone oil type coupling agent etc. are mentioned.

  Although content of the said coupling agent is not specifically limited, 0.1-5 weight part is preferable with respect to 100 weight part of said fillers, and 0.1-2 weight part is especially preferable. When the content is less than the lower limit value, the filler cannot be sufficiently covered, and thus the effect of improving heat resistance may be low. When the content exceeds the upper limit value, the reaction is affected, and the bending strength is reduced. There is.

  The thermosetting resin composition of this invention can add additives other than the said component as needed in the range which does not impair a characteristic. Examples of components other than the above components include surface conditioners such as acrylic polymers, and colorants such as dyes and pigments.

  The resin varnish of the present invention uses a ketone solvent as a solvent. The solvent used in the resin varnish of the present invention is not limited as long as 70% by mass or more of the total is composed of ketones. Alcohols, ethers, acetals, esters, alcohol esters, ether alcohols, and esters A solvent other than ketones such as ethers may be contained in a proportion of less than 30% by mass.

  Examples of the ketones include, but are not limited to, acetone, acetophenone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl-n-butyl ketone, methyl isobutyl ketone, dipropyl ketone, diisobutyl ketone, methyl amyl ketone, and acetonyl acetone. , Isophorone, cyclohexanone, methylcyclohexanone, 2- (1-cyclohexenyl) cyclohexanone, and the like. The ketones are used alone or in combination of two or more. Among these, cyclic ketones are preferable from the viewpoint of solubility of the bismaleimide compound, and cyclohexanone, isophorone, and methylcyclohexanone are particularly preferable. That is, it is preferable that the ketone solvent used in the present invention contains at least one of cyclohexanone, isophorone, and methylcyclohexanone, and the total content of the three types of ketones is 70% by mass or more. Moreover, it is preferable that cyclohexanone is included especially from a viewpoint of a boiling point and productivity. In the present invention, cyclic ketones are saturated or unsaturated alicyclic ketones. Further, the methylcyclohexanone is similarly preferable in any of 2-methylcyclohexanone, 3-methylcyclohexanone, and 4-methylcyclohexanone.

  Although the resin varnish of the present invention is not particularly limited, for example, a method of preparing a slurry in which the filler is dispersed in a solvent, adding other components to the slurry, and further adding the solvent to dissolve and mix, etc. Can be mentioned. By using the slurry, secondary aggregation of the filler can be prevented and dispersibility is improved.

  The solid content of the resin varnish of the present invention is not particularly limited, but is preferably 30 to 80% by weight, and particularly preferably 40 to 70% by weight. When the solid content of the resin varnish is less than the lower limit value, the fluidity of the resin varnish is too high, and when it exceeds the upper limit value, the fluidity of the resin varnish is too low. When the solid content of the resin varnish is within the above range, the fluidity of the resin varnish is good. Therefore, when the prepreg is produced, the retention rate of the resin composition with respect to the glass cloth is high and the workability is excellent.

(Prepreg)
Next, the prepreg of the present invention will be described.
The prepreg of the present invention can be obtained by holding the resin varnish of the present invention described above on a glass cloth and then removing the solvent in the resin varnish. In the heating and drying step during the preparation of the prepreg, the solvent in the resin varnish is removed, and at the same time, the curing reaction of the resin composition contained in the resin varnish proceeds, and the resin layer after heating and drying is in a semi-cured state.
Since the prepreg of the present invention is produced using the above-mentioned resin varnish, the resin and the filler are not separated when the base material is impregnated with the resin varnish even though a large amount of the filler is contained. . Therefore, even when a laminated board is manufactured by heat and pressure molding, appearance defects such as streak-like unevenness do not occur.
In addition, the resin layer of the prepreg of the present invention is slowed by the interaction between the bismaleimide compound and the residual ketone solvent, so that no voids are generated in the semi-cured state. The adhesiveness between the resin layer and the conductor layer when used as a core substrate base material and the circuit embedding property in the resin layer when the prepreg is used as an insulating material for buildup are also excellent.
In addition, the prepreg of the present invention has excellent adhesion with the conductor layer by including the epoxy resin in the resin varnish of the present invention, and excellent in dielectric properties (dielectric constant, dielectric loss tangent) by including the bismaleimide compound, By containing a large amount of filler, it has high elasticity and low thermal expansion, and has a lower dielectric loss tangent.

Examples of the glass cloth include glass woven fabric, glass nonwoven fabric, and glass paper. Among these, a glass woven fabric is preferable from the viewpoint of reducing the linear expansion coefficient.
Although the glass which comprises the said glass cloth is not specifically limited, For example, E glass, C glass, A glass, S glass, D glass, NE glass, T glass, H glass etc. are mentioned. Among these, E glass, T glass, or S glass is preferable. Thereby, the high elasticity of a glass cloth can be achieved and a thermal expansion coefficient can also be made small.

  Examples of the method for impregnating the glass cloth with the resin varnish include a method of immersing the glass cloth in the resin varnish, a method of applying with various coaters, and a method of spraying with a spray. Among these, the method of immersing the glass cloth in the resin varnish is preferable. Thereby, the impregnation property of the thermosetting resin composition with respect to the glass cloth can be improved. In addition, when a glass cloth is immersed in a resin varnish, a normal impregnation coating equipment can be used. As shown in FIG. 1, the glass cloth 1 is immersed in a resin varnish 3 in an impregnation tank 2 to impregnate the glass cloth 1 with the resin varnish 3. In that case, the glass cloth 1 is immersed in the resin varnish 3 by the dip roll 4 (three in FIG. 1) with which the impregnation tank 2 is equipped. Next, the glass cloth 1 impregnated with the resin varnish 3 is pulled up in the vertical direction, and arranged between a pair of squeeze rolls or comma rolls (5 in FIG. 1 is a squeeze roll) arranged in parallel in the horizontal direction. Then, the application amount of the resin varnish 3 to the glass cloth 1 is adjusted. Thereafter, the glass cloth 1 coated with the resin varnish 3 is heated at a predetermined temperature with a dryer 6 to volatilize the solvent in the coated resin varnish and to semi-cure the thermosetting resin composition to prepare a prepreg. 7 is manufactured. Note that the upper roll 8 in FIG. 1 rotates in the same direction as the direction of travel of the prepreg 7 in order to move the prepreg 7 in the direction of travel. Moreover, the conditions which dry the solvent of the said resin varnish 3 can obtain the semi-hardened prepreg 7 by drying at the temperature of 90-180 degreeC for 1 to 10 minutes of time.

The prepreg of the present invention, the glass cloth per unit area weight ^{24g / m 2 ~49g / m 2} , and the weight per unit area of the thermosetting resin composition is at ^48g / ^{m 2 ~279g} / m 2 Preferably there is. If the weight per unit area of the glass cloth and the weight per unit area of the thermosetting resin composition are within the above ranges, the amount of the resin composition held by the glass cloth is large, so that the prepreg has a low dielectric constant and a low dielectric loss tangent. And since the glass cloth is thin, the thickness of the whole prepreg is equal to or less than the conventional thickness.

  In the prepreg of the present invention, the weight per unit area of the thermosetting resin composition is preferably 2 to 5.7 times the weight per unit area of the glass cloth, particularly 3 to 5 times. It is preferable that Thereby, the prepreg has a low dielectric constant and a low dielectric loss tangent.

(Metal-clad laminate)
Next, the metal-clad laminate will be described.
The metal-clad laminate of the present invention is obtained by laminating a metal foil on the above prepreg and heating and pressing. One prepreg may be used, or a laminate in which two or more prepregs are stacked may be used. When using a single prepreg, the metal foil is overlapped on both upper and lower surfaces or one surface. When using the laminated body which laminated | stacked two or more prepregs, metal foil is piled up on the outermost upper and lower surfaces or one side of the laminated body. Next, a metal-clad laminate can be obtained by heat-pressing a laminate of a prepreg and a metal foil.

  Examples of the metal foil include copper, copper alloy, aluminum, aluminum alloy, silver, silver alloy, gold, gold alloy, zinc, zinc alloy, nickel, nickel alloy, tin, tin alloy, Metal foils, such as iron and an iron-type alloy, are mentioned. Moreover, you may form conductor layers, such as the above coppers and copper-type alloys, by plating.

  Although the temperature to heat is not specifically limited, 120-220 degreeC is preferable and especially 150-200 degreeC is preferable. Although the pressure to pressurize is not particularly limited, 0.5 to 5 MPa is preferable, and 1 to 3 MPa is particularly preferable. Moreover, you may perform post-curing at the temperature of 150-300 degreeC with a high temperature tank etc. as needed.

  Since the metal-clad laminate of the present invention uses the prepreg of the present invention, voids are not generated and the adhesion of the metal foil is excellent. In addition, the flow of the resin composition during heat and pressure molding is small, and uneven movement of the molten resin in the metal-clad laminate during heating and pressing is suppressed, preventing streaky irregularities on the surface of the metal-clad laminate. And a uniform thickness.

(Printed wiring board)
Next, the printed wiring board of the present invention will be described.
The printed wiring board of the present invention uses the above metal-clad laminate as an inner layer circuit board.
Or the printed wiring board of this invention uses said prepreg for an insulating layer.

In the present invention, the printed wiring board is a conductor circuit layer formed by providing a conductive layer such as a metal foil on an insulating layer. A single-sided printed wiring board (single-layer board), a double-sided printed wiring board (double-layer board) ) And multilayer printed wiring boards (multilayer boards). A multilayer printed wiring board is a printed wiring board that is laminated in three or more layers by a plated through hole method, a build-up method, or the like, and can be obtained by heating and press-molding an insulating layer on an inner circuit board. .
For the inner layer circuit board, for example, the metal foil of the metal-clad laminate of the present invention is preferably subjected to etching or the like to form a conductor circuit of a predetermined pattern, and the conductor circuit portion is blackened. it can.
As the insulating layer, the prepreg of the present invention can be used. When the prepreg of the present invention is used as the insulating layer, the inner layer circuit board may not be made of the metal-clad laminate of the present invention.

Hereinafter, as a representative example of the printed wiring board of the present invention, a multilayer printed wiring board in which the metal-clad laminate of the present invention is used as an inner circuit board and the prepreg of the present invention is used as an insulating layer will be described.
A circuit is formed on one side or both sides of the metal-clad laminate by a known method such as a subtractive method, an additive method, or a semi-additive method to produce an inner layer circuit board. In some cases, through holes can be formed by drilling or laser processing, and electrical connection on both sides can be achieved by plating or the like. The insulating layer is formed by stacking the prepreg on the inner layer circuit board and molding it by heating and pressing. Similarly, a multilayer printed wiring board can be obtained by alternately and repeatedly forming a conductor circuit layer and an insulating layer by the known method.

  Specifically, the prepreg and the inner layer circuit board are overlapped and vacuum heated and pressed using a vacuum pressurizing laminator device or the like, and then the insulating layer is heated and cured with a hot air dryer 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 carry out heat hardening, If an example is given, it can implement in temperature 140-240 degreeC and time 30-120 minutes.

  Next, the laminated insulating layer is irradiated with a laser to form an opening. As the laser, an excimer laser, a UV laser, a carbon dioxide gas laser, or the like can be used.

  Resin residue (smear) after laser irradiation is preferably removed by an oxidizing agent such as permanganate or dichromate, that is, desmear treatment. If the desmear treatment is insufficient and the desmear property is not sufficiently secured, even if metal plating is applied to the aperture, the conductive properties between the upper and lower conductor circuit layers are sufficient due to smear. May not be secured. Moreover, since the surface of the smooth insulating layer can be simultaneously roughened by performing the desmear treatment, the adhesion of the outer layer circuit formed by metal plating in the next step can be improved. Note that a conductor layer may be formed on the surface of the insulating layer before the opening is formed by laser irradiation.

  Next, a metal plating process is performed on the opening and an outer layer circuit is formed on the surface of the insulating layer by the known method. Conducting the outer hole circuit and the inner layer circuit by conducting metal plating on the opening portion.

  Further, an insulating layer may be laminated and a circuit may be formed in the same manner as described above. However, in the multilayer printed wiring board, a solder resist film is formed on the outermost layer after the circuit is formed. The method for forming the solder resist film is not particularly limited. For example, a method of forming a dry film type solder resist by laminating (laminating), exposing and developing, or printing a liquid resist by exposing and developing. This is done by the forming method. In addition, when using the obtained multilayer printed wiring board for a semiconductor device, the electrode part for a connection is provided in order to mount a semiconductor element. The connection electrode portion can be appropriately coated with a metal film such as gold plating, nickel plating, or solder plating.

(Semiconductor device)
Next, the semiconductor device of the present invention will be described.
A semiconductor element having solder bumps is mounted on the printed wiring board obtained above, and connection to the printed wiring board is attempted through the solder bump. Then, a sealing resin is filled between the printed wiring board and the semiconductor element to form a semiconductor device. The solder bump is preferably made of an alloy made of tin, lead, silver, copper, bismuth or the like.

  The method for connecting the semiconductor element and the printed wiring board is to use a flip chip bonder or the like to align the connection electrode portion on the printed wiring board with the solder bumps of the semiconductor element, and then the IR reflow apparatus, the hot plate In addition, the solder bumps are heated to the melting point or higher by using other heating devices, and the printed wiring board and the solder bumps are connected by fusion bonding. In order to improve connection reliability, a metal layer having a relatively low melting point, such as solder paste, may be formed in advance on the connection electrode portion on the printed wiring board. Prior to this joining step, the connection reliability can be improved by applying a flux to the surface layer of the connection electrode portion on the solder bump and / or printed wiring board.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example and a comparative example, this invention is not limited to this.

Example 1
(1) Preparation of Varnish 8.0 parts by weight of biphenyl aralkyl type epoxy resin (Nippon Kayaku, NC-3000H, epoxy equivalent 285), 9.1 parts by weight of 2,2′-bis [4- (4- Maleimidophenoxy) phenyl] propane (manufactured by Keisei Kasei Co., Ltd., BMI-80), 12.3 parts by weight of phenol novolac type cyanate resin (manufactured by LONZA, Primaset PT-30), 0.1 part by weight of 2-phenylimidazole (Shikoku) 2PZ), 0.5 parts by mass of 3-glycidoxypropyltrimethoxysilane (Shin-Etsu Silicone, KBM-403), 70.0 parts by mass of fused silica particles (manufactured by Admatechs, SO-25R, average) (Particle size 0.5 μm) is added to 42.8 parts by weight of cyclohexanone, and the non-volatile content (solid content) is adjusted to 70% by mass. To obtain a varnish of a curable resin composition.

(2) Manufacture of prepreg Using the varnish obtained above, the varnish is a solid content of the thermosetting resin composition with respect to a glass woven fabric (thickness 0.032 mm, manufactured by Asahi Kasei Electronics) 31 g / m ² . It was impregnated with 151 g / m ² and dried in a drying furnace at 180 ° C. for 5 minutes to prepare a prepreg having a thermosetting resin composition content of 83.0% by mass. At this time, the weight per unit area of the thermosetting resin composition was 4.9 times the weight per unit area of the glass cloth.

(3) Manufacture of metal-clad laminate Four layers of the prepreg obtained above are stacked, and 12 μm thick electrolytic copper foil (F2WS-12, manufactured by Furukawa Circuit Foil) is stacked on the outermost upper and lower surfaces, and the pressure is 4 MPa. Then, heat pressing was performed at a temperature of 220 ° C. for 180 minutes to obtain a double-sided copper clad laminate having a thickness of 0.4 mm.

(4) Manufacture of printed wiring board After conducting through-hole processing on the double-sided copper-clad laminate obtained above using a 0.1 mm drill bit, aiming at conduction between the upper and lower copper foils by electroless plating, The inner layer circuit was formed on both surfaces by etching the copper foils on both surfaces (L (conductor circuit width (μm)) / S (conductor circuit width (μm)) = 50/50).
Next, the chemical | medical solution (Asahi Denka Kogyo Co., Ltd. make, Tech SO-G) which has hydrogen peroxide water and a sulfuric acid as a main component was spray-sprayed to the inner layer circuit, and the unevenness | corrugation formation by a roughening process was performed.
Next, the prepreg was laminated on the inner layer circuit using a vacuum laminator, and heat cured at a temperature of 170 ° C. for 60 minutes to obtain a laminate.
Thereafter, an opening portion (blind via hole) having a diameter of 60 μm is formed on the prepreg of the obtained laminate using a carbonic acid laser device, and a swelling liquid of 70 ° C. (Swelling Dip Securigant P, manufactured by Atotech Japan Co., Ltd.) For 5 minutes, and further immersed in an aqueous potassium permanganate solution (manufactured by Atotech Japan Co., Ltd., Concentrate Compact CP) at 80 ° C. for 15 minutes, followed by neutralization and roughening treatment.
Next, after the steps of degreasing, applying a catalyst, and activating, a power supply layer of about 0.5 μm was formed by an electroless copper plating film. A chromium-deposited film on which a 25 μm-thick UV-sensitive dry film (AQ-2558, manufactured by Asahi Kasei Co., Ltd.) is bonded to the surface of the power feeding layer with a hot roll laminator, and a pattern having a minimum line width / line spacing of 20 μm / 20 μm is drawn. The position was adjusted using a mask (manufactured by Towa Process Co., Ltd.), exposure was performed with an exposure apparatus (UX-1100SM-AJN01 manufactured by Ushio Electric Co., Ltd.), and development was performed with an aqueous sodium carbonate solution to form a plating resist.
Next, electrolytic copper plating (81-HL manufactured by Okuno Pharmaceutical Co., Ltd.) was performed at 3 A / dm ^{2 for} 30 minutes using the power feeding layer as an electrode to form a copper wiring having a thickness of about 25 μm. Here, the plating resist was peeled off using a two-stage peeling machine. Each chemical solution is mainly composed of monoethanolamine solution (R-100 manufactured by Mitsubishi Gas Chemical Co., Ltd.) in the first stage alkaline aqueous solution layer, and potassium permanganate and sodium hydroxide as the main ingredients in the second stage oxidizing resin etchant. An aqueous solution of acidic amine (Mc. Dicer 9279, manufactured by Nihon Mcder Mid Co., Ltd.) was used for neutralization.
Then, the power feeding layer was immersed in an ammonium persulfate aqueous solution (AD-485 manufactured by Meltex Co., Ltd.) to remove the etching, and ensure insulation between the wirings. Next, the insulating layer was finally cured at a temperature of 200 ° C. for 60 minutes, and finally a solder resist (manufactured by Taiyo Ink Co., PSR4000 / AUS308) was formed on the circuit surface to obtain a printed wiring board.

(5) Manufacture of semiconductor device The printed wiring board is a printed wiring board obtained as described above, and is provided with a connection electrode portion subjected to nickel gold plating corresponding to the solder bump arrangement of the semiconductor element. It cut | disconnected and used for the magnitude | size of * 50mm. The semiconductor element (TEG chip, size 15 mm × 15 mm, thickness 0.8 mm) has solder bumps, and the circuit protection film of the semiconductor element was formed of a positive photosensitive resin (CRC-8300, manufactured by Sumitomo Bakelite Co., Ltd.). I used something. In assembling the semiconductor device, first, a flux material was uniformly applied to the solder bumps by a transfer method, and then mounted on a printed wiring board by thermocompression bonding using a flip chip bonder device. Next, after solder bumps were melt-bonded in an IR reflow furnace, a liquid sealing resin (manufactured by Sumitomo Bakelite Co., Ltd., CRP-4152S) was filled and the liquid sealing resin was cured to obtain a semiconductor device. The curing condition of the liquid sealing resin was a temperature of 150 ° C. and 120 minutes.

(Example 2)
Addition amount of 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane (manufactured by Keiai Kasei Co., Ltd., BMI-80), phenol novolac cyanate resin (manufactured by LONZA, Primeset PT-30) contained in the varnish In the same manner as in Example 1, except for changing as shown in Table 1, varnish preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were carried out.

(Example 3)
The biphenyl aralkyl type epoxy resin (Nippon Kayaku, NC-3000H, epoxy equivalent 285) contained in the varnish was changed to a naphthalene skeleton modified cresol novolac epoxy resin (Nippon Kayaku, NC-7300L, epoxy equivalent 230). In the same manner as in Example 1, varnish preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were carried out.

Example 4
Example 1 except that the biphenyl aralkyl type epoxy resin (Nippon Kayaku, NC-3000H, epoxy equivalent 285) contained in the varnish was changed to an anthracene type epoxy resin (Mitsubishi Chemical, YX-8800, epoxy equivalent 210). In the same manner, varnish preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were carried out.

(Example 5)
2.2'-bis [4- (4-maleimidophenoxy) phenyl] propane (manufactured by Keiai Kasei Co., Ltd., BMI-80) contained in the varnish was replaced with bis- (3-ethyl-5-methyl-4-maleimidophenyl) methane ( A varnish was prepared, a prepreg was manufactured, a metal-clad laminate was manufactured, a printed wiring board was manufactured, and a semiconductor device was manufactured in the same manner as in Example 1 except that it was changed to KAI Kasei BMI-70). .

(Example 6)
Except for changing 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane (manufactured by Keiai Kasei, BMI-80) contained in the varnish to polyphenylmethane maleimide (manufactured by Daiwa Kasei, BMI-2300) In the same manner as in Example 1, varnish preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were carried out.

(Example 7)
Biphenyl aralkyl type epoxy resin (Nippon Kayaku, NC-3000H, epoxy equivalent 285), 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane (Kai Kasei, BMI-80) contained in varnish ), Phenol novolac-type cyanate resin (manufactured by LONZA, Primaset PT-30), fused silica particles (manufactured by Admatechs, SO-25R, average particle size 0.5 μm), except for changing the addition amount as shown in Table 1. In the same manner as in Example 1, varnish preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were carried out.

(Example 8)
Biphenyl aralkyl type epoxy resin (Nippon Kayaku, NC-3000H, epoxy equivalent 285), 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane (Kai Kasei, BMI-80) contained in varnish ), Phenol novolac-type cyanate resin (manufactured by LONZA, Primaset PT-30), fused silica particles (manufactured by Admatechs, SO-25R, average particle size 0.5 μm), except for changing the addition amount as shown in Table 1. In the same manner as in Example 1, varnish preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were carried out.

Example 9
Using a varnish of Example 1, a glass woven fabric (thickness 0.039 mm, Asahi Kasei EMD Corporation) with respect to 25 g / ^{m 2,} and varnish is 142g / ^{m 2} impregnated with the solid content of the resin composition, 180 ° C. In the same manner as in Example 1, except that the prepreg having a resin composition content of 85.0% by mass was prepared by drying in a drying furnace, the varnish was prepared, the prepreg was produced, and the metal-clad laminate was produced. Printed wiring boards and semiconductor devices were manufactured. In addition, the weight per unit area of the thermosetting resin composition of the prepreg obtained in Example 9 was 5.7 times the weight per unit area of the glass cloth.

(Example 10)
Using a varnish of Example 1, a glass woven fabric (thickness 0.045 mm, Asahi Kasei EMD Corporation) with respect to 49 g / ^{m 2,} and varnish was 126 g / ^{m 2} impregnated with the solid content of the resin composition, 180 ° C. In the same manner as in Example 1, except that the prepreg having a resin composition content of 73.5% by mass was prepared by drying in a drying oven for 5 minutes, varnish preparation, prepreg production, metal-clad laminate production, Printed wiring boards and semiconductor devices were manufactured. In addition, the weight per unit area of the thermosetting resin composition of the prepreg obtained in Example 10 was 2.6 times the weight per unit area of the glass cloth.

(Example 11)
Except that the solvent of Example 1 was changed to 3-methylcyclohexanone, the same procedure as in Example 1 was followed. Preparation of varnish, manufacture of prepreg, manufacture of metal-clad laminate, manufacture of printed wiring board, manufacture of semiconductor device went.

(Example 12)
A varnish was prepared, a prepreg was manufactured, a metal-clad laminate was manufactured, a printed wiring board was manufactured, and a semiconductor device was manufactured in the same manner as in Example 1 except that the solvent of Example 1 was changed to isophorone.

(Example 13)
Except that the solvent of Example 1 was changed to 32.8 parts by weight of cyclohexanone and 10.0 parts by weight of methyl isobutyl ketone, the same procedure as in Example 1 was carried out to prepare a varnish, to produce a prepreg, to produce a metal-clad laminate, Printed wiring boards and semiconductor devices were manufactured.

(Example 14)
9.5 parts by weight of biphenylaralkyl type epoxy resin (Nippon Kayaku, NC-3000H, epoxy equivalent 285) contained in the varnish, 2.2′-bis [4- (4-maleimidophenoxy) phenyl] propane (KAI 1,3-bis (3-aminophenoxy) benzene (manufactured by Mitsui Chemicals) without using phenol novolac cyanate resin (manufactured by LONZA, Primaset PT-30) instead of 12.5 parts by weight. , APB), except that 7.4 parts by weight were used, varnish preparation, prepreg manufacture, metal-clad laminate manufacture, printed wiring board manufacture, and semiconductor device manufacture were performed in the same manner as in Example 1. .

(Comparative Example 1)
Preparation of varnish and prepreg were carried out in the same manner as in Example 1 except that the addition amount of phenol novolac cyanate resin (manufactured by LONZA, Primaset PT-30) was changed as shown in Table 2 without using a bismaleimide compound. Manufacturing of metal-clad laminates, printed wiring boards, and semiconductor devices.

(Comparative Example 2)
A varnish was prepared in the same manner as in Example 1 except that the amount of biphenylaralkyl type epoxy resin (Nippon Kayaku, NC-3000H, epoxy equivalent 285) was changed as shown in Table 2 without using a bismaleimide compound. Preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production.

(Comparative Example 3)
Preparation of varnish was carried out in the same manner as in Example 4 except that the amount of anthracene epoxy resin (Mitsubishi Chemical, YX-8800, epoxy equivalent 210) was changed as shown in Table 2 without using a bismaleimide compound. Production of prepregs, production of metal-clad laminates, production of printed wiring boards, and production of semiconductor devices were performed.

(Comparative Example 4)
Without using an epoxy resin, 2,2′-bis [4- (4-maleimidophenoxy) phenyl] propane (manufactured by Keiai Kasei Co., Ltd., BMI-80), phenol novolac type cyanate resin (manufactured by LONZA, Primaset PT-30) Except for changing the addition amount as shown in Table 2, the varnish was prepared, the prepreg was manufactured, the metal-clad laminate was manufactured, the printed wiring board was manufactured, and the semiconductor device was manufactured in the same manner as in Example 1. .

(Comparative Example 5)
Except for changing the addition amount of fused silica particles (manufactured by Admatechs, SO-25R, average particle size 0.5 μm) to 30.0 parts by weight as shown in Table 2, in the same manner as in Example 1, Preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were performed.

(Comparative Example 6)
Except for changing the addition amount of fused silica particles (manufactured by Admatechs, SO-25R, average particle size 0.5 μm) to 200.0 parts by weight as shown in Table 2, in the same manner as in Example 1, Preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were performed.

(Comparative Example 7)
Except that the solvent was changed to dimethylformamide, varnish preparation, prepreg production, metal-clad laminate production, printed wiring board production, and semiconductor device production were carried out in the same manner as in Example 1.

(Comparative Example 8)
A varnish was prepared, a prepreg was produced, a metal-clad laminate was produced, a printed wiring board was produced, and a semiconductor device was produced in the same manner as in Example 5 except that the solvent was changed to dimethylformamide.

(Comparative Example 9)
A varnish, a prepreg, a metal-clad laminate, a printed wiring board, and a semiconductor device were manufactured in the same manner as in Example 14 except that the solvent was changed to dimethylformamide.

(Evaluation)
The following evaluation was performed using the metal-clad laminate or the printed wiring board obtained in each Example and each Comparative Example. The evaluation contents are shown together with the items. Moreover, the evaluation result obtained by each Example is shown in Table 1, and the evaluation result obtained by each comparative example is shown in Table 2.

(1) Generation | occurrence | production condition of stripe-shaped unevenness The generation | occurrence | production condition of the stripe-shaped unevenness on the double-sided copper clad laminated board surface obtained by each Example and each comparative example was evaluated visually. The case where no streak-like unevenness was confirmed was defined as “no problem”, and the case where streak-like unevenness was confirmed was defined as “with streak”.

(2) Generation state of voids The double-sided copper-clad laminate obtained in each Example and each Comparative Example was etched on the entire surface, and the generation state of voids was evaluated visually. The case where no void was confirmed was designated as “no problem”, and the case where void was confirmed was designated as “with void”. In addition, since the void which generate | occur | produced in a double-sided copper clad laminated board is a thing which the void which generate | occur | produced in the prepreg hardened | cured by heating and pressurizing, what the void was confirmed by the double-sided copper clad laminated board is the said double-sided copper clad laminated board This means that voids were also generated in the prepreg used in the production of the above.

(3) Thermal expansion coefficient (50-100 ° C)
The double-sided copper-clad laminate obtained in each Example and each Comparative Example was etched on the entire surface, and a test piece of 5 mm × 20 mm was prepared from the obtained laminate, and a TMA (thermomechanical analysis) apparatus (TA instrument) Q400), a temperature range of 30 to 300 ° C., a temperature increase / decrease rate of 10 ° C./min, and a load of 5 g, a temperature increase / decrease temperature of 30 to 300 ° C. is defined as one cycle, and the second cycle 50 to 100 The linear expansion coefficient (CTE) at 0 ° C. was measured.

(4) Copper foil peel strength A 100 mm x 20 mm test piece was prepared from the double-sided copper clad laminate obtained in each of the examples and comparative examples, and the peel strength at 23 ° C was measured. The peel strength measurement was performed according to JIS C 6481.

(5) Dielectric properties The double-sided copper-clad laminate obtained in each example and each comparative example was etched on the entire surface, cut into 97 × 25 mm, 53 × 25 mm, and 38 × 25 mm, and a rolled copper foil of 0.018 mm was attached. Then, a triplate line resonator was prepared, and dielectric constant and dielectric loss tangent were measured by a triplate line resonator method using a microwave network analyzer HP8510C, HP83651A, HP8517B (manufactured by Agilent Technologies).

(6) Circuit embedding property The cross section of the circuit portion of the printed wiring board obtained in each example and each comparative example is polished, and a pressure vessel together with a fluorescent solution (fluorescent penetrant flaw detector, SUPER GLO OD-2800N manufactured by Marktec) The sample was permeated at 125 ° C. and 1.5 atmospheres for 15 minutes, and then the cross section of the circuit portion of the printed wiring board was observed with an epifluorescence microscope. Due to poor circuit embedding, a void portion that could not be embedded occurs between the conductor portion of the circuit and the insulating layer, and the fluorescence penetrating flaw detection agent penetrated into the void portion, and the one where fluorescence was seen was regarded as a “embedding defect” The case where no fluorescence was observed was regarded as “no abnormality”.

In Comparative Example 1, the circuit embedding property was poor because a large amount of cyanate resin was used without using a bismaleimide compound.
In Comparative Example 2, since the bismaleimide compound was not used and a large amount of biphenyl aralkyl type epoxy resin was used, the dielectric loss tangent deteriorated.
In Comparative Example 3, streaky unevenness occurred because a large amount of anthracene type epoxy resin was used without using a bismaleimide compound.
In Comparative Example 4, since no epoxy resin was used, the copper foil peel strength deteriorated.
In Comparative Example 5, since the amount of the filler was small, the thermal expansion coefficient and the dielectric loss tangent were high.
In Comparative Example 6, since the amount of the filler was large, voids were generated, the circuit embedding property was poor, and the copper foil peel strength was deteriorated.
In Comparative Examples 5, 6, and 7, a ketone-based solvent was not used as the solvent, and a nitrogen-containing aprotic polar solvent was used. Therefore, the fluidity of the resin varnish was large and streaky irregularities were generated.
On the other hand, in Examples 1 to 14, excellent dielectric properties, excellent adhesion to the conductor layer and circuit embedding properties, no generation of streaky irregularities and voids, low thermal expansion, excellent copper foil peel strength, etc. The basic required quality was also met.

DESCRIPTION OF SYMBOLS 1 ... Glass cloth 2 ... Impregnation tank 3 ... Resin varnish 4 ... Dip roll 5 ... Squeeze roll 6 ... Dryer 7 ... Prepreg 8 ... Upper roll

Claims (6)

Resin varnish containing a thermosetting resin composition containing a thermosetting resin containing an epoxy resin and a bismaleimide compound and a filler contained in a solid content in a proportion of 60 to 85% by mass in a ketone solvent Is obtained by removing the ketone solvent after holding the glass cloth,
The weight per unit area of glass cloth with ^{24g / m 2 ~49g / m 2} , and the weight per unit area of the thermosetting resin composition is a ^{48g / m 2 ~279g / m 2} ,
Weight per unit area of the thermosetting resin composition, are two-fold ～5.7 Baidea the weight per unit area of the glass cloth,
The prepreg characterized in that the ketone solvent contains at least one of cyclohexanone, isophorone and methylcyclohexanone, and the total content of cyclohexanone, isophorone and methylcyclohexanone is 70% by mass or more . The prepreg according to claim 1, wherein the thermosetting resin further contains a cyanate resin. A metal-clad laminate obtained by laminating a metal foil on the prepreg according to claim 1 or 2 , and heating and pressing the metal foil. A printed wiring board comprising the metal-clad laminate according to claim 3 as an inner layer circuit board. A printed wiring board comprising the prepreg according to claim 1 or 2 as an insulating layer on an inner layer circuit. Wherein a formed by mounting a semiconductor element on a printed wiring board according to claim 4 or 5.

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