JP2002038022A - Insulating resin composition for multilayer printed wiring board, multilayer printed wiring board using the same, and manufacturing method using the same - Google Patents

Abstract

(57) [Abstract] [Problem] High heat resistance, strong toughness, small thermal deformation,
A highly reliable multilayer printed wiring board having an insulating layer having good adhesion to copper wiring is obtained. A resin composition containing a thermosetting resin, a thermoplastic resin, and a filler, wherein the cured product has a fine phase separation structure, and the filler is a thermosetting resin rich phase or a thermoplastic resin. It is unevenly distributed in one of the rich phases.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer printed wiring board used for a semiconductor package or the like and a method for manufacturing the same, and more particularly, to an insulating resin composition used for an interlayer insulating film of a multilayer printed wiring board and a method of manufacturing the same. The present invention relates to the production of an insulating film using the same.

[0002]

2. Description of the Related Art In recent years, with the progress in the electronics field, electronic devices have been reduced in size and speed, and therefore, even in packages directly mounting ICs and LSIs, higher density and higher reliability have been achieved by fine patterns. Is required.

Conventionally, in a package on which an LSI or the like is mounted, there is a problem that cracks or the like occur at a joint boundary due to a difference in thermal expansion coefficient between the LSI and a mounting substrate (interposer), and electrical reliability becomes insufficient. Was.

Therefore, attempts have been made to reduce the thermal expansion coefficient of the interposer by adding a silica filler to the interposer, thereby reducing the difference in thermal expansion coefficient between the mounted object and the mounted object.

[0005] Further, there is a problem that cracks occur in the interposer itself due to a severe durability test, and it is desired to improve the toughness of an insulating material used for a mounting substrate.

In recent years, as an improvement of epoxy resins used for such insulating materials as thermosetting resins, a technique of imparting toughness to a resin by mixing a thermoplastic resin such as polyether sulfone with the epoxy resin has been proposed. (Keizo Yamanaka and Takashi Inoue, Polymer, v
ol. 30, P662 (1989)). The polyethersulfone-modified epoxy resin obtained by mixing two types of resins has improved toughness as compared with the epoxy resin alone. The reason for this is as if the structures were connected to each other and dispersed regularly, and the phase separation structure between an epoxy-rich phase composed mainly of epoxy resin and a polyethersulfone-rich phase composed mainly of polyethersulfone. It is because it forms.

A resin substrate using a thermosetting resin such as an epoxy resin as an insulating layer is used not only as a high-density printed wiring board but also as a substrate for mounting a semiconductor bare chip since it is lightweight and inexpensive. It is becoming. However, the required miniaturization of the conductor pattern tends to progress more and more. At this time, securing the adhesion strength is a problem, but if the unevenness of the surface anchor is increased to solve this problem, the uniformity and reliability of the fine wiring pattern will be impaired, and it may not be possible to achieve both thinning and adhesion strength. Had been a problem.

In order to effectively impart toughness to a brittle thermosetting epoxy resin, it is necessary that the thermosetting resin and the thermoplastic resin form a phase-separated structure after thermosetting. If the thermoplastic resin and the thermosetting resin are uniformly mixed and have an apparently nearly compatible structure, the roughened surface is finely roughened in the surface roughening step during copper plating. Although it is advantageous for forming a fine line, it is effective in increasing the toughness to some extent, but the original toughness of a polymer alloy of a thermosetting resin and a thermoplastic resin cannot be fully utilized. In addition, the thermoplastic resin component having relatively low adhesion strength of copper plating is finely dispersed, and the adhesion strength between the insulating layer and the copper pattern is reduced. On the other hand, when the phase separation structure is rough, although the copper plating strength is improved, the roughened surface of the surface layer is too rough, which hinders the formation of a fine wiring pattern. That is, there has been a problem that it is impossible to form an insulating layer that satisfies all of toughness, plating strength, adhesion strength, and fine patterning of a wiring pattern.

[0009]

SUMMARY OF THE INVENTION A first object of the present invention is to provide a multilayer printed wiring having an insulating layer having high heat resistance, strong toughness, small thermal expansion, and good adhesion to copper wiring. An object of the present invention is to provide an insulating resin composition for a board.

A second object of the present invention is to provide a highly reliable multilayer printed wiring board having an insulating layer having high heat resistance, high toughness, small thermal expansion, and good adhesion to copper wiring. Is to provide.

A third object of the present invention is to provide a highly reliable multilayer printed wiring board having an insulating layer having high heat resistance, high toughness, low thermal expansion, and good adhesion to copper wiring. Is to provide a method for manufacturing a multilayer printed wiring board that can be easily and inexpensively manufactured.

[0012]

The insulating resin composition for a multilayer printed wiring board of the present invention comprises a resin containing the following components (A) thermosetting resin, (B) thermoplastic resin, and (C) filler. A composition, wherein the cured product has a fine phase separation structure, and the filler is unevenly distributed in one of a thermosetting resin-rich phase and a thermoplastic resin-rich phase.

A multilayer printed wiring board according to the present invention comprises a base having a first wiring pattern, an insulating layer formed on the base, and the insulating layer so as to be electrically connected to the first wiring pattern. In the multilayer printed wiring board having the second wiring pattern formed on the layer, the insulating layer contains the following components (A) a thermosetting resin, (B) a thermoplastic resin, and (C) a filler. It is formed by using a resin composition, has a fine phase separation structure, and is characterized in that the filler is unevenly distributed in one of a thermosetting resin-rich phase and a thermoplastic resin-rich phase.

According to the method for manufacturing a multilayer printed wiring board of the present invention, the following components (A) thermosetting resin, (B) thermoplastic resin, and (C) are formed on a substrate having a first wiring pattern.
A step of applying an insulating resin composition containing a filler, and thermally curing the obtained insulating resin coating layer under heating conditions that cause phase separation to form an insulating layer having a fine phase separation structure; Forming a second wiring pattern so as to be electrically connected to the first wiring pattern.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The insulating resin composition for a multilayer printed wiring board of the present invention comprises the following components: (A) a thermosetting resin, (B) a thermoplastic resin, and (C)
It contains a filler, and its cured product has a fine phase separation structure, and the filler is unevenly distributed in either the thermosetting resin rich phase or the thermoplastic resin rich phase in the fine phase separation structure. .

Further, a multilayer printed wiring board of the present invention is formed using the above-mentioned insulating resin composition, and comprises a base material having a first wiring pattern and (A)
It is formed using a resin composition containing a thermosetting resin, (B) a thermoplastic resin, and (C) a filler, has a fine phase separation structure, and the filler has a thermosetting property in the fine phase separation structure. An insulating layer unevenly distributed in either the resin rich phase or the thermoplastic resin rich phase, and a second wiring pattern formed on the insulating layer so as to be electrically connected to the first wiring.

According to the method for producing a multilayer printed wiring board of the present invention, an insulating layer is formed using the above-mentioned insulating resin composition, and the following components ( A) applying an insulating resin composition containing a thermosetting resin, (B) a thermoplastic resin, and (C) a filler,
A step of thermally curing the obtained insulating resin coating layer under a heating condition that causes phase separation to form an insulating layer having a fine phase separation structure, and a step of electrically connecting the first wiring pattern on the insulating layer. Forming a second wiring pattern.

Factors that determine the phase structure include the compatibility of the materials, the curing temperature, the curing speed, and the like. To facilitate the occurrence of phase separation, for example, the compatibility with PES is reduced by using an alkyl-substituted epoxy resin, or in the case of the same composition system, the curing temperature is increased or the curing speed is increased. This can be achieved by slowing down (controlled by the catalyst species).

According to the present invention, an insulating layer obtained by curing an insulating resin composition for a multilayer printed wiring board comprising at least a thermosetting resin, a thermoplastic resin, and a filler is cured by heat after curing. Phase separation between the thermoplastic resin and the thermoplastic resin, forming a fine phase separation structure,
In addition, the filler is selectively present in the thermosetting resin-rich phase or the thermoplastic resin-rich phase, thereby simultaneously satisfying the toughness of the insulating layer, the adhesion strength between the insulating layer and the copper wiring, and the fine patterning of the wiring pattern. Can be.

The fine phase-separated structure in the present invention refers to a fine structure in which the pitch (structure period) of a sea-island structure, a continuous spherical structure, a composite dispersed phase structure, and a bicontinuous phase structure is about 3 μm or less.

Further, when the fine phase separation structure is any of a sea-island structure, a continuous spherical structure or a composite dispersed phase structure,
It is preferable that the filler is unevenly distributed in the spherical domains in the structure. More preferably, the average size of the spherical domains is preferably 0.1 to 5 μm.

If the average diameter of the spherical domains is less than 0.1 μm, sufficient adhesion strength between the insulating resin and copper cannot be obtained in electroless plating after surface roughening, and the effect of toughening the cured product is reduced. If the thickness exceeds 5 μm, the roughened surface becomes too rough in the surface roughening step of copper plating, which tends to be disadvantageous for forming a fine wiring pattern.

Further, it is preferable that the fine phase separation structure is a composite dispersed phase structure or a continuous spherical phase structure, and the filler is unevenly distributed in the thermosetting resin rich phase.

The sea-island structure, the composite dispersed phase structure, and the bicontinuous phase structure (also referred to as a continuous phase structure) are described in “Polymer Alloy”, p. 325 (1993), Tokyo Chemical Industry Co., Ltd.
For the continuous spherical structure, see Keizo Yamanaka and Takashi
Iniue, POLYMER, Vol. 30, pp. 662 (1989).

FIGS. 1 to 4 show model diagrams showing the sea-island structure, the continuous spherical structure, the composite dispersed phase structure, and the bicontinuous phase structure described in these documents.

Such a fine phase-separated structure can be obtained by controlling curing conditions such as the curing speed and reaction temperature of the insulating resin composition, or controlling the compatibility of the insulating resin composition.

For example, in the case of an insulating resin composition containing an epoxy resin, polyethersulfone and silica as main components, first, a polyethersulfone and an epoxy resin are mixed without adding a filler, and when the resin is cured, about 0% is obtained. The material composition which forms a fine continuous spherical structure having a spherical domain of 1 to 5 μm or less is previously determined.
By adding a fine filler made of silica with an average particle diameter of 0.1 to 3 μm and optimizing the reaction temperature and reaction rate again, it has a fine phase separation structure and the filler is selectively contained in the epoxy resin rich To obtain a cured product dispersed therein. The filler can be selectively dispersed only in the epoxy resin rich phase.

FIG. 5 is an electron micrograph showing the surface structure of an example of the insulating resin film thus obtained.

As shown in the figure, the insulating resin film has a bicontinuous phase structure composed of a polyethersulfone-rich phase and an epoxy resin-rich phase, and silica is selectively dispersed only in the epoxy resin-rich phase and unevenly distributed. are doing.

As described above, the insulating resin composition used in the present invention forms a sea-island structure or a continuous spherical structure when no filler is added to the insulating resin composition. Thereby, a fine resin insulating layer having a bicontinuous phase structure or a composite dispersed phase structure can be formed.

The thermosetting resin of component (A) used in the present invention includes, for example, epoxy resin, cyanate resin, bismaleimide, addition polymer of bismaleimide and diamine, phenol resin, resol resin,
Examples include, but are not limited to, isocyanate, triallyl isocyanurate, triallyl cyanurate, and vinyl group-containing polyolefin compounds. Among these thermosetting resins, an epoxy resin is more preferable from the balance of performance such as heat resistance and insulation properties.

As the epoxy resin used in the present invention, known epoxy resins can be used. For example, phenol novolak epoxy resin, cresol novolak epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin Hydrogenated compounds of epoxy compounds containing aromatic ring such as epoxy resin of epoxy type, biphenyl type epoxy resin, epoxy resin of biphenyl novolak type, epoxy resin of trishydroxyphenylmethane type, epoxy resin of tetraphenylethane type and epoxy resin of dicyclopentadiene phenol type , Alicyclic epoxy resins, various derivatives of cyclohexene oxide, and halogen-containing epoxy resins such as tetrabromobisphenol A type epoxy resin. These may be used alone or in combination. Can.

Among them, an epoxy resin having a structure represented by the following chemical formula 1 is more preferably added as a component because it is particularly excellent in heat resistance, surface roughness during copper plating, and the like.

[0034]

Embedded image

When an epoxy resin is used as the thermosetting resin of the present invention, a known epoxy resin curing agent can be used. Examples of such epoxy resin curing agents include polyphenols such as phenol novolak, amine curing agents such as dicyandiamide, diaminodiphenylmethane, diaminodiphenylsulfone, pyromellitic anhydride, trimellitic anhydride, and benzophenonetetracarboxylic acid. Acid anhydride curing agent or a mixture thereof. Among them, the use of polyhydric phenols such as phenol novolak is particularly preferable from the viewpoint of low water absorption.

The mixing ratio of the epoxy resin curing agent can be used in an arbitrary ratio in combination with the epoxy resin, but usually, the mixing ratio is determined so that the glass transition temperature becomes high. For example, when phenol novolak is used as an epoxy resin curing agent, it is preferable to mix the epoxy equivalent and the phenolic hydroxyl group equivalent in a ratio of 1: 1.

As the thermoplastic resin of the component (B) used in the present invention, engineering plastics such as polyether sulfone, polysulfone, and polyphenylene sulfide are preferable from the viewpoint of heat resistance. Further, polyether sulfone which is excellent in various points such as mechanical properties, insulating properties, and solubility in a solvent is more preferable.

As the polyether sulfone used in the present invention, various known polyether sulfones can be used. Examples of the terminal group of such polyether sulfone include a chlorine atom, an alkoxy group, and a phenolic hydroxyl group. In particular, in the present invention, by making the terminal a phenolic hydroxyl group, the affinity with the epoxy resin is improved, and the interaction at the interface between the polyethersulfone-rich phase and the epoxy resin-rich phase can be increased. The mechanical properties are improved, which is more desirable.

The molecular weight of the polyether sulfone resin is preferably from 1,000 to 100,000. Polyethersulfone resins having a molecular weight of 1,000 or less do not have sufficient toughness as polyethersulfone and are not only brittle, but also difficult to form a phase-separated structure with an epoxy resin. There is a tendency that it is difficult to impart toughness. Further, those having a viscosity of 100,000 or more are difficult to handle because they are hardly soluble in a solvent, and tend to form a phase separation structure having a relatively large co-continuous phase when mixed with an epoxy resin. It is disadvantageous.

The mixing ratio of the epoxy resin and the polyethersulfone in the insulating resin composition used in the present invention is from 5% by weight to 4% by weight of the total resin solids based on the content of the polyethersulfone.
It is desirably 0% by weight. When the content of polyether sulfone is 5% by weight or less of the total resin solids, the toughness effect of polyether sulfone tends to be hardly obtained, and when it is 40% by weight or more, sufficient copper adhesion strength tends not to be obtained.

A known curing catalyst can be added to the insulating resin composition used in the present invention for the purpose of accelerating the curing reaction. For example, when an epoxy resin is used as the thermosetting resin, usable curing catalysts include triphenylphosphine, tri-4-methylphenylphosphine, tri-4-methoxyphenylphosphine, tributylphosphine, trioctylphosphine, and tri-2. Organic phosphine compounds such as cyanoethylphosphine and tetraphenylborate salts thereof; tertiary amines such as tributylamine, triethylamine, 1,8-diazabicyclo (5,4,0) undecene-7 and triamylamine; benzyltrimethylammonium chloride And quaternary ammonium salts such as benzyltrimethylammonium hydroxide and triethylammonium tetraphenylborate; and imidazoles such as 2-ethylimidazole and 2-ethyl-4-methylimidazole. Also among these. The use of organic phosphine compounds and imidazoles is particularly preferred.

The curing catalyst may be added in any proportion so as to obtain a desired gel time. Usually, it is preferable to blend the composition such that the gel time of the composition is 1 minute to 15 minutes at each predetermined temperature of 80 ° C to 250 ° C.

As the filler of the component (C) used in the present invention, known fillers can be used. For example, as an organic filler, epoxy resin powder, melamine resin powder,
Urea resin powder, guanamine resin powder, polyester resin powder and the like, and inorganic fillers include silica, alumina, titanium oxide and the like.

The filler preferably has an average particle diameter of 0.1 to 3 μm. If the average particle diameter is less than 0.1 μm, the fillers are liable to agglomerate, the viscosity of the varnish increases, and the handling becomes difficult. In addition to the poor quality, the contribution to the roughening effect in the surface roughening step tends to be too small. If it exceeds 3 μm, the phase separation structure becomes coarse, and the roughened surface in the surface roughening step during copper plating is roughened. Tends to be too rough and not suitable for forming fine wiring patterns.

The insulating resin composition for a multilayer printed wiring board is usually made of an inorganic or organic material for the purpose of improving the adhesion to the electroless plating layer formed on the insulating layer and for reducing the coefficient of thermal expansion. Can be added. Particularly, the silica filler is more preferably used because it has a low dielectric constant, a low coefficient of linear expansion, and is easily detached from the insulating resin by an oxidizing agent treatment in an alkaline atmosphere.

As the silica filler used in the present invention, various types of silica such as various types of synthetic silica synthesized by a wet method, a dry method, crushed silica obtained by crushing silica, and fused silica once melted can be used. Further, since the silica filler that can be used in the present invention needs to be dispersed in the fine phase separation structure for the refinement of the surface shape after chemical roughening,
It is desirable that the average primary particle size is 0.1 to 3 μm.

According to the present invention, when a cross-sectional shape of the insulating resin composition using a filler meeting these conditions is observed using a scanning electron microscope (SEM), a fine phase separation structure is formed. I understood that. further,
EPMA observation showed that the silica filler was selectively present only in the epoxy domain phase that had been phase separated.

In the present invention, the content of the filler is preferably 5% to 40% by weight of the total resin solids. The reason for this is that if the compounding ratio of the filler is higher than 40% by weight, the insulating resin becomes brittle, and the toughness of the thermoplastic resin, particularly polyethersulfone, is not imparted. And it tends to be difficult to obtain sufficient plating strength.

As the solvent used in the coating solution of the insulating resin composition of the present invention, a solvent that does not remain in the coating layer when the coating layer is dried and baked is preferably used. Further, since polyether sulfone has a high molecular weight and is easily gelled in a solvent, it is preferable to select a solvent compatible with polyether sulfone. For example, acetone, methyl ethyl ketone (MEK), toluene, xylene, n-hexane, methanol, ethanol, methyl cellosolve, ethyl cellosolve, cyclohexanone, N, N-dimethylacetamide,
Methyl isobutyl ketone (MIBK), 4-butyrolactone, dimethylformamide (DMF), n-methyl-2-pyrrolidone (NMP) or a mixture thereof is used.

Further, in the insulating resin composition of the present invention, if necessary, additives such as a thermal polymerization inhibitor, a plasticizer, a leveling agent, an antifoaming agent, an ultraviolet absorber, a flame retardant, and the like. It is possible to add a coloring pigment or the like.

Next, as a preferred example of a method for manufacturing a multilayer printed wiring board using the insulating material of the present invention, a so-called built-up method will be specifically described.

First, a base material having a first wiring pattern is prepared.

The substrate to be used includes, for example, a plastic substrate, a ceramic substrate, a metal substrate, a film substrate, etc. Specifically, a glass epoxy substrate, a bismaleimide-triazine substrate, an aramid fiber nonwoven substrate, a liquid crystal polymer substrate, An aluminum substrate, an iron substrate, a polyimide substrate, or the like can be preferably used.

Next, the above-mentioned insulating material is applied to the substrate having the first wiring pattern, and then dried and thermally cured to form a resin insulating layer.

As a method of forming the resin insulating layer on the substrate having the first wiring pattern, for example, the above-mentioned insulating resin composition is coated by a roller coating method, a dip coating method, a spray coating method, a spinner coating method, a curtain coating method. Law,
A method of applying by various means such as a slot coating method and a screen printing method, or a method of applying a resin film obtained by processing a mixed solution containing an insulating resin composition into a film shape can be applied. The preferable thickness of the resin insulating layer is usually about 20 to 100 μm, but may be larger when particularly high insulating property is required.

The heating conditions at this time are preferably 60
Pre-curing at a temperature of from 120 to 120 ° C for 30 minutes to 2 hours;
Performing time curing. More preferably, 60
Pre-curing at a temperature of from 100 to 100 ° C. for 40 minutes to 1.5 hours;
Performing time curing.

For example, when the epoxy resin represented by the chemical formula (1) is used, if the pre-curing temperature is lower than 60 ° C.
It is difficult to volatilize the solvent in the resin, and the reaction rate becomes extremely slow because the curing reaction does not proceed, and it is not enough to freeze the phase structure in the film while keeping it fine. There is a tendency that the phase separation speed becomes too high as compared with the curing speed, so that a fine phase separation structure cannot be formed, and the structural period of the obtained cured product becomes large, so that it is not suitable for a fine pattern.

If the curing is lower than 150 ° C., it is insufficient to cure the epoxy resin to a high glass transition point, and the curing time for achieving full curing (complete curing) becomes extremely long. On the other hand, when the temperature is 220 ° C. or more, or when it exceeds 4 hours, deterioration of the core substrate or deterioration of the resin insulating layer due to heat tends to occur, and the copper wiring layer tends to be oxidized. If the time is less than 30 minutes, the thermosetting reaction tends to be insufficient.

Thereafter, if necessary, the surface of the resin insulation layer can be polished.

Further, if necessary, the surface of the resin insulating layer can be subjected to a surface roughening treatment using an acid or an oxidizing agent.

Thereafter, a metal layer for forming a wiring pattern is formed by performing electroless plating and electrolytic plating on the resin insulating layer. As a method of the electroless plating, for example, it is preferable to use at least one of electroless copper plating, electroless nickel plating, electroless gold plating, electroless silver plating, and electroless tin plating. In addition, after performing electroless plating, it is also possible to perform further different types of electroless or electrolytic plating, or coat with solder.

In order to make electrical connection with each wiring pattern, via holes can be formed in the roughened resin insulating layer by using, for example, a laser or the like. As laser, CO2 gas laser or UV / YAG
A laser, an excimer laser, or the like can be used. When a laser is used, a via hole smaller in size than a via hole formed by so-called photolithography can be obtained. For example, in photolithography,
Via holes with a diameter of about 80 μm are formed, but UV / YA
With G lasers, via holes with a minimum diameter of about 30 μm can be obtained.

The via hole is preferably formed before forming the electroless plating metal on the resin insulating layer. This is because if the via hole is formed after the electroless plating metal layer is formed, the via hole has no metal layer, so that electroplating cannot be performed, and as a result, the via hole cannot be conducted.

By performing electroplating using the obtained electroless plating metal layer as an electrode, an electroplating metal layer can be formed on the electroless plating metal layer.

By patterning the obtained copper plating metal layer, a second wiring pattern can be formed.

The wiring pattern can also be obtained by performing electroplating after patterning the electroless plating metal layer (semi-additive method).

On the thus obtained second wiring pattern, wiring can be laminated by repeatedly applying the above-described steps. By using such a build-up method, a finer multilayer wiring board can be easily formed.

[0068]

EXAMPLES Examples are given below to specifically describe the insulating resin composition and the multilayer printed wiring board of the present invention.
Here, the cross-sectional structure of each insulating resin was observed using an SEM. The composition of each phase was identified by EPMA.

Example 1 First, 100.0 parts by mass of a heat-resistant epoxy resin (TMH574 / trade name of Sumitomo Chemical Co., Ltd.), 46.5 parts by mass of a flame-retardant epoxy resin (E5050 / trade name of Yuka Shell Co., Ltd.), a phenol resin ( 61.6 parts by mass of Nippon Kayaku Co., Ltd. and 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P, Sumitomo Chemical Co., Ltd.)
It was dissolved in a mixed solvent of 4-butyrolactone and n-methyl-2-pyrrolidone.

In this solution, 127.4 parts by mass of a silica filler (1-FX / trade name, manufactured by Tatsumori) and 0.3 parts by mass of a curing catalyst 2E4MZ (manufactured by Tokyo Chemical Industry Co., Ltd.) were dispersed by a kneading roll, and then stirred. And defoaming to obtain an insulating resin composition for a multilayer printed wiring board.

FIG. 6 is a diagram illustrating an example of a method for manufacturing a multilayer wiring board according to the present invention.

FIG. 7 is a block diagram for explaining a manufacturing process of a multilayer wiring according to the present invention.

As shown in FIG. 6A, first, a glass epoxy substrate 1 having a copper wiring pattern 2 subjected to blackening treatment on both sides was prepared. As shown in FIG.
On the above, the above-mentioned insulating resin composition for a multilayer printed wiring board is applied to a thickness of about 50 μm by a spin coater, and then heat-cured at 80 ° C. for 1 hour using a drying oven, and subsequently at 180 ° C. for 2 hours. Was performed to form the resin insulating layer 3. As shown in FIG. 6C, the surface of the resin insulating layer was polished.

Next, as shown in FIG. 6D, a via hole 5 was formed in the surface of the resin insulating layer 3 by UV / YAG laser processing, and the surface reached the copper wiring pattern 2.
Thereafter, as shown in FIG. 6 (e), unnecessary burrs and the like were removed by smear removal treatment by chemical roughening using a chemical solution, and then electroless plating was performed.

Thereafter, as shown in FIG. 6F, electroplating was performed using the obtained electroless plating layer 4 as an electrode to form a copper plating layer 6 having a thickness of about 18 μm, thereby obtaining a test sample. As shown in FIG. 6 (g), a multilayer printed wiring board can be obtained by etching the copper plating layer using an etching solution.

The following test was conducted on the obtained sample.
And evaluation. Table 1 shows the results. Table 1 also shows the phase separation structure of a resin insulating layer cured using a composition similar to the above-described insulating resin composition except that no filler was added.

Adhesion Strength Test The adhesion strength was determined by a 90 ° peel test of a 1 cm wide pattern based on JIS-C6481.

Test of ability to form fine conductor layer In order to examine the ability to form a fine conductor layer, a LINE / S
A fine pattern of PACE = 20 μm / 20 μm was formed by a semi-additive method, and the pattern shape was observed with an optical microscope. A wiring pattern without a bottom defect from the top was evaluated as good, particularly a part of the bottom edge part was evaluated as defective in the edge part, and a wiring pattern with a poor degree was evaluated as defective.

The resin insulating layer undergoes spinodal decomposition upon curing, forms a fine phase-separated structure between the polyfunctional epoxy resin and polyethersulfone, and the filler is substantially selective to the polyfunctional epoxy resin phase region. Was confirmed to be present.

Thermal shock test To examine the toughness of the insulating resin layer, the substrate was heated at -65 to 150 ° C.
A thermal shock test of 2000 cycles was performed to check for cracks on the insulating resin layer.

Insulation Reliability Test In order to examine the insulation reliability of the resin insulation layer, insulation resistance was measured for 100 hours under conditions of 121 ° C., 85%, and 20 V using a counter electrode pattern having a diameter of 1 cmφ. Those having a resistance value of 10 ⁶ Ω or more were regarded as acceptable.

Reflow Reliability Test In order to check the reflow reliability of the plating pattern, the board provided with various conductor patterns was subjected to pretreatment of moisture absorption storage under JEDEC LEVEL 1 conditions, and then subjected to a solder reflow test at a temperature of 260 ° C. The test was performed five times, and defects such as pattern peeling were observed. If no peeling occurred in any of the tests, it was considered OK.
The case where the pattern was peeled off in the fourth and fifth tests was evaluated as small pattern peeling, and the case where the pattern was peeled in the first to third tests was evaluated as large pattern peeling.

In this example, the wiring is formed only on one side of the substrate, but it is also possible to form the wiring on both sides.

Example 2 First, 100.0 parts by mass of a heat-resistant epoxy resin (TMH574 / trade name of Sumitomo Chemical Co., Ltd.), 46.5 parts by mass of a flame-retardant epoxy resin (E5050 / trade name of Yuka Shell Co., Ltd.), and a phenol resin ( 61.6 parts by mass of Nippon Kayaku Co., Ltd. and 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P, Sumitomo Chemical Co., Ltd.)
It was dissolved in a mixed solvent of 4-butyrolactone and n-methyl-2-pyrrolidone.

This solution was mixed with a silica filler (NIPGEL CX-
200 / trade name of Nippon Silica Industry Co., Ltd.) 127.4 parts by mass and curing agent 2E4MZ (Tokyo Kasei Kogyo Co., Ltd.) 0.3 parts by mass are dispersed with a kneading roll, and then stirred and defoamed to provide insulation for a multilayer printed wiring board. A resin composition was obtained.

Next, a printed wiring board was prepared and evaluated in the same manner as in Example 1 using the insulating resin composition. Table 1 shows the obtained results.

Example 3 First, 100.0 parts by mass of a heat-resistant epoxy resin (EOCN103S / trade name of Nippon Kayaku Co., Ltd.), 46.5 parts by mass of flame-retardant epoxy resin (E5050 / trade name of Yuka Shell Co., Ltd.), and phenol resin ( 61.6 parts by mass of Nippon Kayaku Co., Ltd. and 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P, Sumitomo Chemical Co., Ltd.)
-Butyrolactone and n-methyl-2-pyrrolidone in a mixed solvent.

The silica filler (ADMAFINE SO-
C2 / Admatex product name) 127.4 parts by mass and curing catalyst
After mixing 0.3 parts by mass of 2E4MZ (manufactured by Tokyo Chemical Industry Co., Ltd.) with a kneading roll, the mixture was stirred and defoamed to obtain an insulating resin composition for a multilayer printed wiring board.

Next, a printed wiring board was prepared and evaluated in the same manner as in Example 1 using the insulating resin composition. Table 1 shows the obtained results.

Example 4 First, 100.0 parts by mass of a heat-resistant epoxy resin (EPPN502H / trade name of Nippon Kayaku Co., Ltd.), 46.5 parts by mass of flame-retardant epoxy resin (E5050 / trade name of Yuka Shell Co., Ltd.), phenol resin ( 61.6 parts by mass of Nippon Kayaku Co., Ltd. and 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P, Sumitomo Chemical Co., Ltd.)
-Butyrolactone and n-methyl-2-pyrrolidone in a mixed solvent.

The silica filler (ADMAFINE SO-
C2 / Admatechs (product name) 127.4 parts by mass and curing catalyst 2E4MZ (Tokyo Kasei Kogyo Co., Ltd.) 0.3 parts by mass are dispersed by a kneading roll, and then stirred and defoamed to form an insulating resin composition for a multilayer printed wiring board. I got something.

Next, the above insulating resin composition was subjected to a heat curing treatment in a drying oven at 180 ° C. for 2 hours.
Hereinafter, creation of a printed wiring board in the same manner as in Example 1,
An evaluation was performed. Table 1 shows the obtained results.

[0093]

[Table 1]

Comparative Example 1 First, 100.0 parts by mass of a heat-resistant epoxy resin (MY721 / trade name, manufactured by Ciba-Geigy), 46.5 parts by mass of a flame-retardant epoxy resin (E5050 / oiled shell), and a phenol resin (manufactured by Nippon Kayaku Co., Ltd.)
61.6 parts by mass and 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P manufactured by Sumitomo Chemical Co., Ltd.) were dissolved in a mixed solvent of 4-butyrolactone and n-methyl-2-pyrrolidone.

In this solution, a silica filler (ADMAFINE SO-
C2 / Admatex product name) 127.4 parts by mass and curing catalyst
After mixing 0.3 parts by mass of 2E4MZ (manufactured by Tokyo Chemical Industry Co., Ltd.) with a kneading roll, the mixture was stirred and defoamed to obtain an insulating resin composition for a multilayer printed wiring board.

Next, using the above insulating resin composition, 18
A resin layer was formed at 0 ° C. for 2 hours, and a printed wiring board was prepared and evaluated in the same manner as in Example 1. Table 2 shows the obtained results.

Comparative Example 2 First, 100.0 parts by mass of a heat-resistant epoxy resin (157S70 / trade name, manufactured by Nippon Kayaku Co., Ltd.), 46.5 parts by mass of a flame-retardant epoxy resin (E5050 / oiled shell), and a phenol resin (Nippon Kayaku Co., Ltd.) 6)
1.6 parts by mass and 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P manufactured by Sumitomo Chemical Co., Ltd.) were dissolved in a mixed solvent of 4-butyrolactone and n-methyl-2-pyrrolidone.

127.4 parts by mass of a silica filler (1-FX / trade name, manufactured by Tatsumori) and 0.3 parts by mass of a curing catalyst 2E4MZ (manufactured by Tokyo Kasei Kogyo Co., Ltd.) were dispersed in this solution with a kneading roll, followed by stirring and defoaming. Thus, an insulating resin composition for a multilayer printed wiring board was obtained.

Next, a printed wiring board was prepared and evaluated in the same manner as in Example 1 using the insulating resin composition. Table 2 shows the obtained results.

Comparative Example 3 First, 100.0 parts by mass of a heat-resistant epoxy resin (TMH574 / manufactured by Sumitomo Chemical Co., Ltd.), 46.5 parts by mass of a flame-retardant epoxy resin (E5050 / oiled shell), and a phenol resin (manufactured by Nippon Kayaku Co., Ltd.) 6
1.6 parts by mass, 89.2 parts by mass of polyether sulfone (manufactured by Sumitomo Chemical Co., Ltd.) were mixed with 4-butyrolactone and n-methyl-2-
It was dissolved in a mixed solvent of pyrrolidone.

[0101] A silica filler (NIPGEL CX-60) was added to this solution.
0 / Nippon Silica Industry Co., Ltd.) 127.4 parts by mass and curing catalyst 2
0.3 parts by mass of E4MZ (manufactured by Tokyo Chemical Industry Co., Ltd.) was dispersed by a kneading roll, and then stirred and defoamed to obtain an insulating resin composition for a multilayer printed wiring board.

Next, a printed wiring board was prepared and evaluated in the same manner as in Example 1 using the insulating resin composition. Table 2 shows the obtained results.

Comparative Example 4 First, 100.0 parts by mass of a heat-resistant epoxy resin (TMH574 / manufactured by Sumitomo Chemical Co., Ltd.), 46.5 parts by mass of a flame-retardant epoxy resin (E5050 / oiled shell), and a phenol resin (manufactured by Nippon Kayaku Co., Ltd.) 6
1.6 parts by mass and 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P manufactured by Sumitomo Chemical Co., Ltd.) were dissolved in a mixed solvent of 4-butyrolactone and n-methyl-2-pyrrolidone.

In this solution, 127.4 parts by mass of a resin filler (SBX-6 / trade name of Sekisui Chemical Co., Ltd.) and 0.3 part by mass of a curing catalyst 2E4MZ (manufactured by Tokyo Kasei Kogyo Co., Ltd.) were dispersed by a kneading roll, then stirred and dispersed. Degassing was performed to obtain an insulating resin composition for a multilayer printed wiring board.

Next, a printed wiring board was prepared and evaluated in the same manner as in Example 1 using the insulating resin composition. Table 2 shows the obtained results.

Comparative Example 5 First, 100.0 parts by mass of a heat-resistant epoxy resin (TMH574 / manufactured by Sumitomo Chemical Co., Ltd.), 46.5 parts by mass of a flame-retardant epoxy resin (E5050 / oiled shell), and a phenol resin (manufactured by Nippon Kayaku Co., Ltd.) 6
1.6 parts by mass, 89.2 parts by mass of polyether sulfone (Sumika Excel 5003P manufactured by Sumitomo Chemical Co., Ltd.), curing catalyst 2E4M
0.3 parts by mass of Z (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in a mixed solvent of 4-butyrolactone and n-methyl-2-pyrrolidone.

Next, a printed wiring board was prepared and evaluated in the same manner as in Example 1 using the insulating resin composition. Table 2 shows the obtained results.

[0108]

[Table 2]

As shown in Tables 1 and 2, it was confirmed that the heat-resistant epoxy TMH574, EOCN103S and EPPN502H formed a fine continuous spherical structure of 0.1 μm to 5 μm when cured without adding a filler. On the other hand, heat-resistant epoxy MY
When cured without adding a filler, 721 was a compatible structure in which a clear phase-separated structure could not be confirmed by SEM observation, and the heat-resistant epoxy 157S70 formed a domain of a continuous spherical structure having a size of 5 μm or more.

From the above Examples and Comparative Examples, it was found that the adhesion strength was increased by dispersing a silica filler in the insulating resin of the present invention. On the other hand, it was found that the heat-resistant epoxy MY721 used in Comparative Example 1 had low adhesion strength. It was presumed that this insulating resin did not have a fine phase-separated structure, so that the toughness of the thermoplastic resin, polyethersulfone, was not sufficiently imparted.

When a polyfunctional epoxy which forms a domain of 5 μm or less when cured without adding a filler is used and a silica filler having a particle size of 0.1 to 3 μm is used, LINE / SPACE = 20/20 μm It has been found that a fine wiring pattern can be formed. Further, it has been found that the insulating resin having the fine wiring pattern formed thereon has high resistance to thermal shock test in all compositions.

It has been found that, when a silica filler and a resin filler prepared by a dry process are used, it is possible to maintain insulation and to have heat resistance.

[0113]

According to the present invention, an insulating layer having high heat resistance, high toughness, little thermal deformation, and good copper wire adhesion can be obtained, whereby a highly reliable multilayer printed wiring board can be obtained. Is provided, which can be easily and inexpensively manufactured.

[Brief description of the drawings]

FIG. 1 is a model diagram showing a sea-island structure.

FIG. 2 is a model diagram showing a continuous spherical structure.

FIG. 3 is a model diagram showing a composite dispersed phase structure.

FIG. 4 is a model diagram showing a bicontinuous phase structure.

FIG. 5 is an electron micrograph showing a surface structure of an example of an insulating resin film.

FIG. 6 is a diagram for explaining an example of the method for manufacturing a multilayer printed wiring board according to the present invention.

FIG. 7 is a block diagram for explaining an example of a manufacturing process of the multilayer printed wiring board according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base material 2, 7 ... Wiring pattern 3 ... Insulating resin layer 4 ... Electroless plating layer 5 ... Via hole 6 ... Plating layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 1/03 610 H05K 1/03 610L 610R 3/46 3/46 TB (72) Inventor Koji Murata Tokyo 1-5-1, Taito, Tokyo Taito-ku, Toppan Printing Co., Ltd. (72) Inventor Kenji Kawamoto 1-15-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. (72) Inventor Toshiaki Hayashi Tsukuba, Ibaraki Kitahara, Ichigo 6 Sumitomo Chemical Co., Ltd. (72) Inventor Noriaki Saito 6, Kitahara, Tsukuba, Ibaraki Prefecture Sumitomo Chemical Co., Ltd. (Reference) 4J002 BJ001 CC041 CC163 CC183 CC193 CD001 CD003 CD051 CD061 CD071 CD111 CD121 CF003 CM021 CN012 CN032 DE136 DE146 DJ016 FD013 FD016 FD140 5E346 AA12 CC09 CC10 CC16 CC32 CC37 CC38 CC39 CC40 DD03 DD25 FF15 GG15 HH11 HH18

Claims (18)

[Claims] 1. A resin composition containing the following components (A) thermosetting resin, (B) thermoplastic resin, and (C) filler, wherein the cured product has a fine phase separation structure, and The insulating resin composition for a multilayer printed wiring board, wherein the filler is unevenly distributed in one of a thermosetting resin-rich phase and a thermoplastic resin-rich phase. 2. The multilayer printed wiring board according to claim 1, wherein the fine phase separation structure is one of a sea-island structure, a continuous spherical structure, a composite dispersed phase structure, and a bicontinuous phase structure. Insulating resin composition. 3. The fine phase-separated structure is one of a sea-island structure, a continuous spherical structure, and a composite dispersed phase structure, and the filler is unevenly distributed in spherical domains in the structure. 3. The insulating resin composition for a multilayer printed wiring board according to the above. 4. The insulating property for a multilayer printed wiring board according to claim 2, wherein the fine phase separation structure is a bicontinuous phase structure, and the filler is unevenly distributed in a thermosetting resin rich phase. Resin composition. 5. The microphase-separated structure is one of a sea-island structure, a continuous spherical structure, and a composite dispersed phase structure,
The insulating resin composition for a multilayer printed wiring board according to claim 2, wherein the filler is unevenly distributed in these spherical domains having an average diameter of 0.1 to 5 µm. 6. The insulating resin composition according to claim 1, wherein the thermosetting resin is made of an epoxy resin. 7. The thermosetting resin has the following structural formula (1): (In the formula, n represents the average number of repetitions, takes a value of 1 to 10, and R independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 5 to 7 carbon atoms, or A hydrocarbon group having 6 to 20 carbon atoms including a cycloalkyl group having 5 to 7; and i is independently an integer of 1 to 4;
When i is 2 or more, R may be the same or different, and Gly represents a glycidyl group. The insulating resin composition for a multilayer printed wiring board according to claim 6, which is an epoxy resin represented by the formula: 8. The insulating resin composition for a multilayer printed wiring board according to claim 1, wherein the thermoplastic resin is polyether sulfone. 9. The method according to claim 8, wherein the thermoplastic resin is a phenol-terminated polyether sulfone.
3. The insulating resin composition for a multilayer printed wiring board according to the above. 10. The thermoplastic resin has a total resin solid content of 5%.
10 to 40% by mass.
The insulating resin composition for a multilayer printed wiring board according to any one of the above. 11. The insulating resin composition for a multilayer printed wiring board according to claim 1, wherein the filler is an inorganic filler. 12. The insulating resin composition for a multilayer printed wiring board according to claim 11, wherein the inorganic filler is silica. 13. The insulating resin composition of claim 12, wherein the filler has an average particle size of 0.1 to 3 μm. 14. The insulating resin composition for a multilayer printed wiring board according to claim 1, wherein the filler has a compounding ratio of 5 to 40% by mass based on the total solid content of the resin composition. object. 15. A base material having a first wiring pattern, an insulating layer formed on the base material, and a second insulating layer formed on the insulating layer so as to be electrically connected to the first wiring pattern. In the multilayer printed wiring board having the wiring pattern of 2, the insulating layer is formed using a resin composition containing the following components (A) a thermosetting resin, (B) a thermoplastic resin, and (C) a filler. A multilayer printed wiring board having a fine phase separation structure, and wherein the filler is unevenly distributed in one of a thermosetting resin-rich phase and a thermoplastic resin-rich phase. 16. An insulating resin composition containing the following components (A) a thermosetting resin, (B) a thermoplastic resin, and (C) a filler is coated on a substrate having a first wiring pattern. Thermally curing the obtained insulating resin coating layer under a heating condition that causes phase separation to form an insulating layer having a fine phase separation structure; and electrically connecting the insulating layer to the first wiring pattern. A method for manufacturing a multilayer printed wiring board, comprising the step of forming a second wiring pattern. 17. The method according to claim 16, wherein the second wiring pattern is formed by electroless plating and electrolytic plating. 18. The heating condition is 60 to 120 ° C.
Pre-curing for 30 minutes to 2 hours,
Carrying out curing at 50 to 220 ° C. for 30 minutes to 4 hours.