JP2996945B2 - Raw material composition for preparing adhesive for electroless plating and method for preparing adhesive for electroless plating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a raw material composition for preparing an adhesive for electroless plating and a method for preparing an adhesive for electroless plating.

[0002]

2. Description of the Related Art In recent years, so-called build-up multilayer wiring boards have been receiving attention due to a demand for higher density of the multilayer wiring boards. This build-up multilayer wiring board is manufactured by a method disclosed in, for example, Japanese Patent Publication No. 4-55555. That is, an interlayer resin insulating layer made of a photosensitive electroless plating adhesive is applied on the core substrate, dried, exposed and developed to form an interlayer resin insulating layer having a via hole opening. Then, after the surface of the interlayer resin insulating layer is roughened by treatment with an oxidizing agent or the like, a plating resist obtained by exposing and developing a photosensitive resin layer on the roughened surface is provided. A conductive circuit pattern including via holes is formed by applying electroless plating to a portion where no resist is formed, and such a process is repeated a plurality of times to obtain a multilayered build-up wiring board.

Japanese Patent Application Laid-Open No. 7-340048 discloses a build-up wiring board manufactured by such a method. As an adhesive for electroless plating used for an interlayer resin insulating layer, it is difficult to cure an acid or an oxidizing agent by curing. There has been proposed a composition in which cured heat-resistant resin particles that are soluble in an acid or an oxidizing agent are dispersed in a composite resin matrix composed of an uncured thermosetting resin and a thermoplastic resin that becomes soluble. .

[0004]

However, when such an adhesive for electroless plating is mass-produced industrially, it is necessary to store the adhesive until it is applied to a substrate when actually producing a printed wiring board. There is. Therefore, during this storage, the adhesive for electroless plating has a problem that the curing gradually progresses, the viscosity of the resin increases, and the adhesive cannot be applied.

An object of the present invention is to suppress the curing of the adhesive which is inevitably generated during the storage of the adhesive, whereby the adhesive for electroless plating having predetermined physical properties can be surely printed. It is intended to provide for the manufacture of boards.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies for realizing the above-mentioned object, and as a result, have conceived an invention having the following features as the main constitutions. That is, the raw material compositions for preparing the adhesive for electroless plating according to the present invention are prepared in advance in the following forms: A resin composition containing an uncured thermosetting resin which becomes hardly soluble in an acid or an oxidizing agent by a curing treatment; A resin composition containing heat-resistant resin particles which have been subjected to a curing treatment soluble in an acid or an oxidizing agent, a thermoplastic resin and an organic solvent; The hardener composition is prepared so that it can be mixed, and the resin composition, the resin composition, and the hardener composition are kept separated from each other, and the separated state immediately before being used as an adhesive for electroless plating. Are mixed and stirred.

Further, the method for preparing the adhesive for electroless plating according to the present invention is a method for preparing an uncured thermosetting resin, a thermoplastic resin curing agent composition and an organic compound which becomes hardly soluble in an acid or an oxidizing agent by a curing treatment. In preparing an adhesive for electroless plating, a thermosetting resin particle soluble in an acid or an oxidizing agent is dispersed in a composite resin matrix composed of a solvent. A resin composition containing an uncured thermosetting resin which becomes hardly soluble in an acid or an oxidizing agent by a curing treatment; A resin composition containing heat-resistant resin particles which have been subjected to a curing treatment soluble in an acid or an oxidizing agent, a thermoplastic resin and an organic solvent; The curing agent composition is separately held in the resin composition, the resin composition, and the curing composition, respectively, and the above-mentioned respective compositions in the isolated state are mixed and stirred immediately before use as an adhesive for electroless plating. It is characterized by the following.

In the raw material composition for preparing the adhesive for electroless plating and the method for preparing the adhesive for electroless plating, the thermosetting resin is obtained by substituting a part of the thermosetting functional group with a photosensitive group. Preferably, the curing agent composition,
It is preferable to include a curing agent for the thermosetting resin and a photoinitiator.

The raw material composition for preparing an adhesive for electroless plating according to the present invention comprises an uncured thermosetting resin, a thermoplastic resin, a curing agent composition, which becomes hardly soluble in an acid or an oxidizing agent by a curing treatment. In a composite resin matrix composed of an organic solvent, a composition for preparing an adhesive for electroless plating obtained by dispersing cured heat-resistant resin particles soluble in an acid or an oxidizing agent, and a curing agent component. Other resin components
, And holds in the isolated state, there is a feature in the point that isolates also was what resin composition and the resin composition.

As a result, in the raw material composition according to the present invention, the curing of the resin component does not progress and the viscosity does not increase even after one month or more. As a result, the adhesive for electroless plating made of this raw material composition had no problem in applicability when actually applied to a substrate in manufacturing a printed wiring board. In the raw material composition according to the present invention, even when the resin component is sensitized, the photopolymerization reaction of the resin component does not proceed. As a result, the adhesive for electroless plating made of this raw material composition is actually applied to a substrate in the manufacture of a printed wiring board and is exposed when exposed.
No reduction in resolution is seen.

In the present invention, the reason for separating the resin composition from the resin composition is that if they are mixed, an increase in viscosity is observed.

On the other hand, the method for preparing an adhesive for electroless plating according to the present invention is characterized in that the above-mentioned isolated compositions are stirred and mixed immediately before being used as an adhesive for electroless plating. There is.

According to the above method for preparing an adhesive according to the present invention, the time from mixing of the composition to use as an adhesive is extremely short, so that the electroless method can secure predetermined physical properties with little increase in viscosity and the like. The plating adhesive can be reliably provided for the manufacture of a printed wiring board.

In the present invention, the adhesive for electroless plating is prepared by stirring and mixing each composition using a roll kneader, a ball mill, a bead mill or the like. For example, there is a method in which the resin composition is firstly kneaded with a roll, mixed and adjusted by a ball mill or a bead mill, and then the resin composition and the curing agent composition are added to the resin composition, followed by mixing and stirring.

In the raw material composition for preparing the adhesive for electroless plating and the method for preparing the adhesive for electroless plating as described above, the thermosetting resin in the resin composition has a part of the thermosetting functional group. Is preferably substituted with a photosensitive group to impart photosensitivity. The reason for this is that if an adhesive containing a thermosetting resin imparted with photosensitivity as a resin component is used, an opening for a via hole can be easily formed in the adhesive layer by exposure and development.

As the thermosetting resin, epoxy resin, phenol resin, polyimide resin and the like can be used. In particular, as the epoxy resin, a novolak type epoxy resin, an alicyclic epoxy resin, or the like can be used. In the case of photosensitization, methacrylic acid, acrylic acid, or the like is subjected to an acrylation reaction with a thermosetting group. Particularly, acrylate of epoxy resin is most suitable.

Incidentally, the resin composition may contain a photosensitive monomer or an antifoaming agent. Examples of the photosensitive monomer include Alonix M325 and M315 manufactured by Toa Gosei and DP manufactured by Nippon Kayaku.
E-6A, R-604 manufactured by Kyoeisha Chemical, and the like can be used. As the defoaming agent, a silicone-based defoaming agent, S-65 manufactured by San Nopco, or the like can be used.

The thermoplastic resin in the resin composition includes:
Polyether sulfone, polysulfone, polyphenylene sulfone, polyphenylene sulfide, polyphenyl ether, polyether imide, and the like can be used.

The heat-resistant resin particles in the resin composition may be a mixture of fine particles having an average particle diameter of 2 μm or less and coarse particles having an average particle diameter of more than 2 μm and 10 μm or less, or a mixture of fine particles having an average particle diameter of less than 2 μm and It is desirable to use a mixture of particles. The former is a full additive method,
The latter is preferably used in the semi-additive method.

As the resin component of the heat resistant resin particles,
Epoxy resin, amino resin (melamine resin, urea resin,
Guanamine resin) and bismaleimide-triazine resin. In particular, the epoxy resin can be arbitrarily prepared to be soluble in an acid or an oxidizing agent or hardly soluble by appropriately selecting the type of oligomer and the type of curing agent. For example, a resin obtained by curing a bisphenol A type epoxy resin oligomer with an amine curing agent is very soluble in chromic acid. However, a resin obtained by curing a cresol novolak type epoxy resin oligomer with an imidazole curing agent is not easily dissolved in chromic acid.

Examples of the organic solvent in the resin composition include glycol ether solvents having the following structural formula, such as diethylene glycol dimethyl ether (DMDG) and triethylene glycol dimethyl ether (DMTG);
It is desirable to use -methylpyrrolidone (NMP) or the like. CH ₃ O— (CH ₂ CH ₂ O) _n —CH ₃ (n = 1 to 5)

The curing agent composition preferably contains a curing agent for a thermosetting resin and a photoinitiator. The reason for this is to ensure that the exposure and development treatment of the adhesive and the subsequent heat curing treatment are performed.

As the curing agent, an imidazole curing agent is preferable, and a liquid that is liquid at 25 ° C. is particularly preferably used.
Examples of such a liquid imidazole curing agent include 1-benzyl-2-methylimidazole (product name: 1B2MZ) and 1-cyanoethyl-2-ethyl-4-methylimidazole (product name: 2E4M).
Z-CN), 4-methyl-2-ethylimidazole (product name: 2E4M
Z) can be used. The addition amount of the imidazole curing agent is desirably 1 to 10% by weight based on the total solid content of the resin composition. The reason for this is that if the added amount is within this range, uniform mixing is easy.

Incidentally, a photoinitiator and a photosensitizer may be added to the curing agent composition. As a photoinitiator, Irgacure I-907 or benzophenone manufactured by Ciba Geigy can be used, and as a photosensitizer, DETX-S or Michler's ketone manufactured by Nippon Kayaku can be used.

The weight ratio of the thermosetting resin of the resin composition to the thermoplastic resin of the resin composition is 1/4 to 4 /
It is desirably 1. This is because the optimum range can improve the toughness of the thermosetting resin. The amount of the organic solvent in the resin composition is desirably 100 to 300 parts by weight based on 100 parts by weight of the thermoplastic resin component. It is desirable that the amount of the curing agent of the curing agent composition be 1 to 10% by weight based on the total solid content of the adhesive for electroless plating.

[0026]

【Example】

(Example 1) (Full additive method) Raw material composition for preparing adhesive for electroless plating (raw material composition according to the present invention) [Resin composition] 80 wt% of 25% acrylate of cresol novolac type epoxy resin (Nippon Kayaku, molecular weight 2500)
% Of a resin solution dissolved in DMDG at a concentration of 35%, 4 parts by weight of a photosensitive monomer (Alonix M315, manufactured by Toagosei Co., Ltd.), 0.5 parts by weight of an antifoaming agent (S-65, manufactured by San Nopco), N
3.6 parts by weight of MP were obtained by stirring and mixing. [Resin composition] Polyether sulfone (PES) 12
Parts by weight, 12.08 parts by weight of an epoxy resin particle (manufactured by Sanyo Chemical Industries, polymer pole) having a mean particle size of 3.0 μm, and 4.83 parts by weight of an epoxy resin particle having a mean particle size of 0.5 μm, and then 30 parts by weight of NMP were added. Then, it was obtained by stirring and mixing with a bead mill. [Curing agent composition] Imidazole curing agent (Shikoku Chemicals,
2E4MZ-CN), 2 parts by weight of a photoinitiator (Circa Geigy, Irgacure I-907), 0.2 parts by weight of a photosensitizer (Nippon Kayaku, DETX-S), and 1.5 parts by weight of NMP are stirred and mixed. I got it.

Each of the resin composition, the resin composition and the curing agent composition is kept in an isolated state,
Stored at 25 ° C. for one month.

B. Raw material composition for preparing interlayer resin insulation agent [Resin composition] 80 wt% of 25% acrylate of cresol novolak type epoxy resin (Nippon Kayaku, molecular weight 2500)
% Of a resin solution dissolved in DMDG at a concentration of 35%, 4 parts by weight of a photosensitive monomer (Alonix M315, manufactured by Toagosei Co., Ltd.), 0.5 parts by weight of an antifoaming agent (S-65, manufactured by San Nopco), N
3.6 parts by weight of MP were obtained by stirring and mixing. [Resin composition] Polyether sulfone (PES) 12
After mixing 14.49 parts by weight of an epoxy resin particle (manufactured by Sanyo Chemical Industries, polymer pole) having an average particle size of 0.5 μm, 30 parts by weight of NMP was further added, and the mixture was stirred and mixed with a bead mill. [Curing agent composition] Imidazole curing agent (Shikoku Chemicals,
2E4MZ-CN), 2 parts by weight of a photoinitiator (Circa Geigy, Irgacure I-907), 0.2 parts by weight of a photosensitizer (Nippon Kayaku, DETX-S), 1.5 parts by weight of NMP I got it.

Each of the resin composition, the resin composition and the curing agent composition is kept in an isolated state,
Stored at 25 ° C. for one month. The interlayer resin insulating agent is a resin composition used as a lower insulating layer in an interlayer resin insulating layer composed of an adhesive layer and an insulating layer.

C. Raw material composition for resin filler preparation [Resin composition] 100 parts by weight of bisphenol F type epoxy monomer (manufactured by Yuka Shell, molecular weight 310, YL983U), having an average particle diameter of 1.6 μm coated with a silane coupling agent on the surface SiO ₂ spherical particles (Admatech, CRS 11
01-CE, where the maximum particle size is 170 parts by weight of the inner layer copper pattern described below (15 μm or less) and 1.5 parts by weight of a leveling agent (manufactured by San Nopco, Perenol S4) by stirring and mixing. The viscosity of the mixture is 23 ± 1
The temperature was adjusted to 45,000-49,000 cps at ℃. [Curing agent composition] Imidazole curing agent (Shikoku Chemicals,
2E4MZ-CN) 6.5 parts by weight.

Each of the resin composition and the curing agent composition was kept isolated and stored at 25 ° C. for one month.

D. Raw material composition for preparing liquid plating resist [Resin composition] 100 parts by weight of a photosensitizing oligomer (molecular weight 4000) in which 50% of epoxy groups of cresol novolak type epoxy resin (manufactured by Nippon Kayaku) are acrylated, dissolved in methyl ethyl ketone 80% by weight of bisphenol A
32 parts by weight of epoxy resin (made by Yuka Shell, Epicoat 1001), 6.4 parts by weight of photosensitive monomer, polyvalent acrylic monomer (Nippon Kayaku, R604), polyvalent acrylic monomer also made of photosensitive monomer (Kyoeisha Chemical Made, DPE6A)
3.2 parts by weight, and then add a leveling agent (Kyoeisha Chemical, Polyflow No. 75) to the total weight of 100 parts by weight.
The mixture was obtained by mixing 0.5 parts by weight and stirring and mixing. [Curing agent composition] Imidazole curing agent (Shikoku Chemicals,
2E4MZ-CN) 3.4 parts by weight, 2 parts by weight of photoinitiator (Circa Geigy, Irgacure I-907), 0.2 part by weight of photosensitizer (Nippon Kayaku, DETX-S), 1.5 parts by weight of NMP I got it.

Each of the resin composition and the curing agent composition was kept in an isolated state and stored at 25 ° C. for one month.

E. Manufacture of printed wiring board (1) 18 μm on both sides of substrate 1 made of glass epoxy resin or BT (bismaleimide triazine) resin having a thickness of 1 mm
A copper-clad laminate on which m copper foils 8 were laminated was used as a starting material (see FIG. 1). First, the copper-clad laminate is drilled, subjected to an electroless plating treatment, and etched in a pattern to form an inner copper pattern 4 on both surfaces of the substrate 1.
And a through hole 9 were formed.

(2) The substrate having the inner layer copper pattern 4 and the through hole 9 formed thereon was washed with water and dried, and then used as an oxidation bath (blackening bath) as NaOH (10 g / l) and NaClO ₂ (40 g / l).
l), Na ₃ PO ₄ (6 g / l), NaOH (10 g
/ L), a roughened layer 11 was provided on the surface of the inner layer copper pattern 4 and the through hole 9 by oxidation-reduction treatment using NaBH ₄ (6 g / l) (see FIG. 2).

(3) The raw material composition for preparing the resin filler C was mixed and kneaded to obtain a resin filler 10. (4) The resin filler 10 obtained in the above (3) is applied to both sides of the substrate using a roll coater within 24 hours after the preparation, thereby filling the space between the conductor circuits 4 or the inside of the through hole 9;
After drying at 70 ° C. for 20 minutes, the resin filler 10 is similarly applied to the other surface between the conductor circuits 4 or through holes 9.
And dried by heating at 70 ° C. for 20 minutes (see FIG. 3).

(5) The surface of the inner layer copper pattern 4 and the through holes 9 are formed on one surface of the substrate after the treatment of the above (4) by belt sanding using # 600 belt polishing paper (manufactured by Sankyo Rikagaku). Polishing was performed so that the resin filler 10 did not remain on the land surface, and then buffing was performed to remove scratches due to the belt sander polishing. Such a series of polishing was similarly performed on the other surface of the substrate. Next, a heat treatment was performed at 100 ° C. for 1 hour, at 120 ° C. for 3 hours, at 150 ° C. for 1 hour, and at 180 ° C. for 7 hours to cure the resin filler 10 (see FIG. 4).

In this manner, the surface layer portion of the resin filler 10 filled in the through holes 9 and the like and the roughened layer 11 on the upper surface of the inner conductor circuit 4 are removed to smooth both surfaces of the substrate.
A wiring board is firmly adhered to the side surface of the inner conductor circuit 4 via the roughened layer 11 and the inner wall surface of the through hole 9 is tightly adhered to the resin filler 10 via the roughened layer 11. Obtained. That is, by this step, the surface of the resin filler 10 and the surface of the inner layer copper pattern 4 become flush with each other. Here, the Tg point of the filled cured resin is 155.6 ° C., and the coefficient of linear thermal expansion is 44.5 × 10 ⁻⁶ /
° C.

(6) The inner conductor circuit 4 and the through-hole 9 exposed in the processing of (5) have a thickness of 2.5 μm
A roughened layer (concavo-convex layer) 11 made of a Cu—Ni—P alloy was formed, and a Sn layer having a thickness of 0.3 μm was provided on the surface of the roughened layer 11 (see FIG. 5; Is not shown). The formation method is as follows. That is, the substrate was acid-degreased and soft-etched, and then treated with a catalyst solution comprising palladium chloride and an organic acid to provide a Pd catalyst. After activating this catalyst, copper sulfate 8 g / l, nickel sulfate 0.6 g / l, citric acid 15 g / l, sodium hypophosphite 29 g / l, boric acid 31 g / l, surfactant 0.1 g
Then, plating was performed in an electroless plating bath consisting of / l and pH = 9 to form a roughened layer 11 of a Cu-Ni-P alloy on the upper surface of the copper conductor circuit 4 and the upper surface of the land of the through hole 9. Then, tin borofluoride 0.1 mol / l, thiourea 1.0 mol / l, temperature 50
C., a Cu-Sn substitution reaction was performed under the conditions of pH = 1.2,
Was provided with a 0.3 μm-thick Sn layer on the surface thereof.

(7) The raw material composition for preparing the interlayer resin insulating agent B was mixed with stirring and adjusted to a viscosity of 1.5 Pa · s to obtain an interlayer resin insulating agent (for lower layer). The raw material composition for preparing the adhesive for electroless plating of A was stirred and mixed, and the viscosity was adjusted to 7 Pa · s to obtain an adhesive solution for electroless plating (for upper layer).

(8) The interlayer resin insulating material (for lower layer) having a viscosity of 1.5 Pa · s obtained in the above (7) is applied to both surfaces of the substrate of the above (6) by a roll coater within 24 hours after preparation. In a horizontal position
Leave for 20 minutes, then dry at 60 ° C for 30 minutes (pre-bake)
Was performed to form an insulating agent layer 2a. Further, the photosensitive adhesive solution (for the upper layer) having a viscosity of 7 Pa · s obtained in the above (7) is applied on the insulating layer within 24 hours after preparation, and left in a horizontal state for 20 minutes. Then, drying (prebaking) was performed at 60 ° C. for 30 minutes to form an adhesive layer 2b (see FIG. 6).

(9) In the above (8), the insulating layer 2a and the adhesive layer
A photomask film on which a black circle of 85 μmφ was printed was brought into close contact with both surfaces of the substrate on which 2b was formed, and was exposed at 500 mJ / cm ² using an ultra-high pressure mercury lamp. This is spray-developed with a DMTG solution, and the substrate is further subjected to an ultra-high pressure mercury lamp for 30 minutes.
Exposure at 00 mJ / cm ² , heat treatment at 100 ° C. for 1 hour, 120 ° C. for 1 hour, and then at 150 ° C. for 3 hours (post bake)
To form a 35 μm thick interlayer resin insulating layer (two-layer structure) 2 having an opening of 85 μmφ (via hole forming opening 6) having excellent dimensional accuracy equivalent to a photomask film (see FIG. 7). ). Note that the tin plating layer was partially exposed in the opening serving as the via hole.

(10) The substrate having the openings formed therein is immersed in chromic acid for 2 minutes to dissolve and remove the epoxy resin particles present on the surface of the adhesive layer 2b of the interlayer resin insulation layer 2.
The surface of the interlayer resin insulating layer 2 was roughened, and then immersed in a neutralizing solution (manufactured by Shipley Co., Ltd.) and then washed with water (FIG. 8).
reference). Further, by applying a palladium catalyst (manufactured by Atotech) to the surface of the substrate subjected to the surface roughening treatment (roughening depth: 6 μm), a catalyst nucleus is formed on the surface of the interlayer resin insulating layer 2 and the via hole opening 6. Was.

(11) The raw material composition for preparing a liquid plating resist of D was stirred and mixed to obtain a liquid plating resist. (12) The liquid plating resist is applied on both sides of the substrate after the catalyst nucleation treatment in the step (10) using a roll coater, and dried at 60 ° C. for 30 minutes to form a resist layer having a thickness of 30 μm. Was formed. Next, a photomask film on which a conductive circuit pattern was drawn was placed on the resist layer, and the resist layer was exposed to ultraviolet light of 400 mJ / cm ² . Then, after removing the photomask film, the resist layer is dissolved and developed with DMTG to form a plating resist on the substrate where the conductor circuit pattern portion has been removed, and further exposed to 6000 mJ / cm ² using an ultra-high pressure mercury lamp. A heat treatment was performed at 100 ° C. for 1 hour and then at 150 ° C. for 3 hours to form a permanent resist 3 on the interlayer resin insulating layer 2 (see FIG. 9).

(13) Pre-plating treatment (specifically, activation of catalyst nuclei) is applied to the substrate on which the permanent resist 3 has been formed.
Then, primary plating was performed using an electroless copper-nickel alloy plating bath having the following composition to form a copper-nickel-phosphorous plating thin film having a thickness of about 1.7 μm on the non-resist-forming portion. At this time, the temperature of the plating bath was 60 ° C,
The plating immersion time was 1 hour. Complexing agent: Na ₃ C ₆ H ₅ O ₇ : 0.23 M (60 g / l) Reducing agent: NaPH ₂ O ₂ .H ₂ O: 0.19 M (20 g / l) pH regulator: NaOH: 0.75 M (pH = 9.5) Stabilizer: Lead nitrate: 0.2 mM (80 ppm) Surfactant: 0.05 g / l Precipitation rate is 1.7 μm / hour

(14) The substrate subjected to the primary plating is pulled out of the plating bath, the plating bath attached to the surface is washed away with water, and the substrate is treated with an acidic solution to obtain copper-nickel-phosphorus. The oxide film on the surface of the plating thin film was removed. Then, without performing Pd substitution, a secondary plating is performed on the copper-nickel-phosphorous plating thin film using an electroless copper plating bath having the following composition, so that the outer layer conductor pattern 5 required as a conductor layer by the additive method is formed. And via holes (BVH) 7 were formed. At this time, the temperature of the plating bath was 50 to 70 ° C., and the plating immersion time was 90 to 360 minutes. Metal salts _{... CuSO 4 · 5H 2 O:} 8.6 mM Complexing agent ... TEA: 0.15 M reducing agent ... HCHO: 0.02 M Others ... stabilizer (bipyridyl, potassium ferrocyanide and the like): a small amount deposition rate, 6 [mu] m / Time

(15) After the conductor layer (about 15 μm thick) is formed by the additive method in this way, one surface of the substrate is coated with the surface of the permanent resist 3 by belt sander polishing using # 600 belt polishing paper. And the upper surface of the copper in the via hole 7 was polished. Subsequently, buffing was performed to remove the scratches caused by the belt sander (only buffing may be performed). Then, the other surface was similarly polished to form a printed wiring board having both surfaces smooth (see FIG. 10).

(16) Copper sulfate 8 g / l, nickel sulfate 0.6 g / l, citric acid 15 g / l, sodium hypophosphite 29 g / l, boric acid 31 g / l, surfactant 0.1 g / l Immersed in an electroless plating solution having a pH of 9 and a thickness of 3 μm
A roughened layer 11 made of a Cu—Ni—P alloy was formed (see FIG. 11). Further, by repeating the above-mentioned steps, a further conductive layer was formed by the additive method, and a wiring layer was built up in this way to obtain a multilayer wiring board.

(17) On the other hand, 60% by weight dissolved in DMDG
Cresol novolak epoxy resin (Nippon Kayaku)
46.67 g of a photosensitizing oligomer (molecular weight 4000) obtained by acrylizing 50% of the epoxy groups of epoxy resin, 15.0 g of an 80 wt% bisphenol A type epoxy resin (made by Yuka Shell, Epicoat 1001) dissolved in methyl ethyl ketone, imidazole curing 1.6 g of an agent (2E4MZ-CN, manufactured by Shikoku Chemicals Co., Ltd.) and a polyacrylic monomer (R604, manufactured by Nippon Kayaku, a photosensitive monomer)
3 g), 1.5 g of polyvalent acrylic monomer (Kyoeisha Chemical, DPE6A), and a dispersion defoaming agent (San Nopco,
S-65) of 0.71 g, and 2 g of benzophenone (Kanto Chemical) as a photoinitiator was added to the mixture.
0.2 of Michler's ketone (Kanto Chemical) as photosensitizer
g was added to obtain a solder resist composition whose viscosity was adjusted to 2.0 Pa · s at 25 ° C. The viscosity was measured using a B-type viscometer (Tokyo Keiki, DVL-B type) at 60 rpm and the rotor No.
In the case of 4, 6 rpm, the rotor No. 3 was used.

(18) The multilayer wiring board obtained in (16) is
After applying a Pd catalyst and activating this catalyst, copper sulfate 8 g
/ L, nickel sulfate 0.6g / l, citric acid 15g / l, sodium hypophosphite 29g / l, boric acid 31g / l, surfactant 0.1g / l, pH = 9 in an electroless plating bath
Cu-Ni-P alloy plating is applied, and a roughened layer 11
Was formed. The solder resist composition was applied to both sides of the multilayer wiring board in a thickness of 20 μm. Then 70
° C. for 20 minutes, after the drying process for 30 minutes was carried out at 70 ° C., a circle pattern (mask pattern) is brought into close contact with a photomask film having a thickness of 5mm drawn is placed, with ultraviolet 1000 mJ / cm ² Exposure and DMTG development processing. And even 80
1 hour at 100 ° C, 1 hour at 100 ° C, 1 hour at 120 ° C, 150 ° C
Heat treatment under the conditions of 3 hours, to open the solder pad portion (including the via hole and its land portion) (opening diameter
A 200 μm) solder resist layer (thickness: 20 μm) 14 was formed.

(19) Next, the substrate on which the solder resist layer 14 has been formed is subjected to a pH of 30 g / l of nickel chloride, 10 g / l of sodium hypophosphite, and 10 g / l of sodium citrate.
= 5 for 20 minutes to form a nickel plating layer 15 having a thickness of 5 μm at the opening. Further, the substrate was placed on an electroless gold plating solution comprising 2 g / l of potassium gold cyanide, 75 g / l of ammonium chloride, 50 g / l of sodium citrate, and 10 g / l of sodium hypophosphite at 93 ° C. for 23 seconds. By dipping, a gold plating layer 16 having a thickness of 0.03 μm was formed on the nickel plating layer 15.

(20) Then, a solder paste is printed in the opening of the solder resist layer 14 and reflowed at 200 ° C. to form a solder bump (solder body) 17. A printed wiring board having the solder bump 17 is formed. Manufactured (see FIG. 12).

Comparative Example 1 Multilayer printed wiring was carried out in the same manner as in Example 1 except that the adhesive having the following composition was used as the adhesive for electroless plating for the upper layer constituting the interlayer resin insulating layer. Boards were manufactured. 35% by weight of 25% acrylate of cresol novolak type epoxy resin (manufactured by Nippon Kayaku, molecular weight 2500), polyether sulfone (PE
S) 12 parts by weight, imidazole curing agent (Shikoku Chemicals, 2E4M
Z-CN) 2 parts by weight, photosensitive monomer (Toa Gosei Co., Aronix M315) 4 parts by weight, photoinitiator (Ciba Geigy,
2 parts by weight of Irgacure I-907) and 0.2 parts by weight of a photosensitizer (DETX-S manufactured by Nippon Kayaku) were mixed, and the average particle size of epoxy resin particles (Polymer Pole manufactured by Sanyo Chemical Industries) was added to the mixture. 12.08 parts by weight having a diameter of 3.0 μm, 4.83 parts by weight of a particle having an average particle diameter of 0.5 μm, and 0.5 parts by weight of an antifoaming agent (S-65 manufactured by San Nopco) were mixed, and further mixed while adding 30 parts by weight of NMP. Thus, a photosensitive adhesive for electroless plating having a viscosity of 3.0 Pa · s was obtained.

The photosensitive adhesive for electroless plating was heated at 25 ° C.
When stored for one month, the resin cured and could not be applied.

(Example 2) (Semi-additive method) Raw material composition for preparing adhesive for electroless plating (raw material composition according to the present invention) [Resin composition] 80 wt% of 25% acrylate of cresol novolac type epoxy resin (Nippon Kayaku, molecular weight 2500)
35% by weight of a resin solution dissolved in DMDG at a concentration of 3.15% and a photosensitive monomer (Toa Gosei Co., Aronix M315) 3.15
Parts by weight, 0.5 parts by weight of an antifoaming agent (manufactured by San Nopco, S-65)
3.6 parts by weight of NMP were obtained by stirring and mixing. [Resin composition] Polyether sulfone (PES) 12
Weight part, epoxy resin particles (manufactured by Sanyo Chemical Co., polymer pole) having an average particle diameter of 1.0 μm, 7.2 parts
After mixing 3.09 parts by weight of 0.5 μm, further add NM
P30 parts by weight was added, and the mixture was stirred and mixed with a bead mill to obtain. [Curing agent composition] Imidazole curing agent (Shikoku Chemicals,
2E4MZ-CN), 2 parts by weight of a photoinitiator (Circa Geigy, Irgacure I-907), 0.2 parts by weight of a photosensitizer (Nippon Kayaku, DETX-S), and 1.5 parts by weight of NMP are mixed with stirring. I got it.

Each of the resin composition, the resin composition and the curing agent composition is kept in an isolated state,
Stored at 25 ° C. for one month.

B. Raw material composition for preparing interlayer resin insulation agent [Resin composition] 80 wt% of 25% acrylate of cresol novolak type epoxy resin (Nippon Kayaku, molecular weight 2500)
% Of a resin solution dissolved in DMDG at a concentration of 35%, 4 parts by weight of a photosensitive monomer (Alonix M315, manufactured by Toagosei Co., Ltd.), 0.5 parts by weight of an antifoaming agent (S-65, manufactured by San Nopco), N
3.6 parts by weight of MP were obtained by stirring and mixing. [Resin composition] Polyether sulfone (PES) 12
After mixing 14.49 parts by weight of an epoxy resin particle (manufactured by Sanyo Chemical Industries, polymer pole) having an average particle size of 0.5 μm, 30 parts by weight of NMP was further added, and the mixture was stirred and mixed with a bead mill. [Curing agent composition] Imidazole curing agent (Shikoku Chemicals,
2E4MZ-CN), 2 parts by weight of a photoinitiator (Circa Geigy, Irgacure I-907), 0.2 parts by weight of a photosensitizer (Nippon Kayaku, DETX-S), 1.5 parts by weight of NMP I got it.

Each of the resin composition, the resin composition and the curing agent composition is kept in an isolated state,
Stored at 25 ° C. for one month. The interlayer resin insulating agent is a resin composition used as a lower insulating layer in an interlayer resin insulating layer composed of an adhesive layer and an insulating layer.

C. Production of Printed Wiring Board (1) Steps (1) to (6) of Example 1 were performed (FIGS. 1 to 5).
reference). (2) The raw material composition for preparing the interlayer resin insulating agent of B was stirred and mixed, and the viscosity was adjusted to 1.5 Pa · s to obtain an interlayer resin insulating agent (for lower layer). The raw material composition for preparing the adhesive for electroless plating of A was stirred and mixed, and the viscosity was adjusted to 7 Pa · s to obtain an adhesive solution for electroless plating (for upper layer).

(3) The interlayer resin insulating material (for lower layer) having a viscosity of 1.5 Pa · s obtained in the above (2) is applied to both surfaces of the substrate by a roll coater within 24 hours after the preparation, and is applied in a horizontal state. After standing for 60 minutes, drying (prebaking) was performed at 60 ° C. for 30 minutes to form an insulating layer 2a. Further, on this insulating layer,
Apply the photosensitive adhesive solution (for upper layer) having a viscosity of 7 Pa · s obtained in (2) within 24 hours after preparation, leave it in a horizontal state for 20 minutes, and then dry at 60 ° C for 30 minutes ( (Prebaking) to form an adhesive layer 2b (see FIG. 6).

(4) In the above (3), the insulating layer 2a and the adhesive layer
A photomask film on which a black circle of 85 μmφ was printed was brought into close contact with both surfaces of the substrate on which 2b was formed, and was exposed at 500 mJ / cm ² using an ultra-high pressure mercury lamp. This is spray-developed with a DMTG solution, and the substrate is further subjected to an ultra-high pressure mercury lamp for 30 minutes.
Exposure at 100 mJ / cm ² and heat treatment (post-bake) at 100 ° C. for 1 hour and then at 150 ° C. for 5 hours
85μ with excellent dimensional accuracy equivalent to a photomask film
Thickness with mφ opening (via hole forming opening 6)
A 35 μm interlayer resin insulating layer (two-layer structure) 2 was formed (see FIG. 7). Note that the tin plating layer was partially exposed in the opening serving as the via hole.

(5) The substrate subjected to the treatment of (4) is immersed in chromic acid for 1 minute to dissolve and remove the epoxy resin particles present on the surface of the adhesive layer 2b of the interlayer resin insulating layer 2. Then, the surface of the interlayer resin insulating layer 2 was roughened, and then immersed in a neutralizing solution (manufactured by Shipley Co., Ltd.) and then washed with water (see FIG. 8). Further, by applying a palladium catalyst (manufactured by Atotech) to the surface of the substrate subjected to the surface roughening treatment, a catalyst nucleus was attached to the surface of the interlayer resin insulating layer 2 and the inner wall surface of the via hole opening 6.

(6) The substrate was immersed in an electroless copper plating bath having the following composition to form a 1.6 μm thick electroless copper plating film 12 on the entire rough surface (see FIG. 13). [Electroless plating solution] EDTA 150 g / l Copper sulfate 20 g / l HCHO 30 ml / l NaOH 40 g / l α, α'-bipyridyl 80 mg / l PEG 0.1 g / l [Electroless plating conditions] 70 ° C. 30 minutes at liquid temperature

(7) Electroless copper plating film formed in (6)
A commercially available photosensitive dry film was stuck on 12 and a mask was placed thereon, exposed at 100 mJ / cm ² , developed with 0.8% sodium carbonate, and provided with a plating resist 3 having a thickness of 15 μm (see FIG. 14). ).

(8) Next, electrolytic copper plating was performed on the non-resist-formed portion under the following conditions to form an electrolytic copper plating film 13 having a thickness of 15 μm (see FIG. 15). [Electroplating solution] Sulfuric acid 180 g / l Copper sulfate 80 g / l Additive (captoside GL, manufactured by Atotech Japan) 1 ml / l [Electroplating conditions] Current density 1 A / dm ² hours 30 minutes Temperature Room temperature

(9) After the plating resist 3 is peeled off with 5% KOH, the electroless plating film under the plating resist 3 is removed.
12 was dissolved and removed by etching with a mixed solution of sulfuric acid and hydrogen peroxide to form a conductor circuit (including via holes) 5 having a thickness of 18 μm and comprising an electroless copper plating film 12 and an electrolytic copper plating film 13 ( See Figure 16).

(10) The substrate on which the conductor circuit 5 is formed is made of copper sulfate 8 g / l, nickel sulfate 0.6 g / l, citric acid 15 g / l
1, sodium hypophosphite 29 g / l, boric acid 31 g / l,
A surface roughening layer 11 made of copper-nickel-phosphorus having a thickness of 3 [mu] m was formed on the surface of the conductor circuit 5 by immersing in an electroless plating solution having a pH of 9 containing 0.1 g / l of a surfactant (see FIG. 17). ). At this time, the formed roughened layer 11 is applied to EPMA (fluorescent X
Line analyzer), Cu: 98 mol%, Ni:
The composition ratio was 1.5 mol%, P: 0.5 mol%. further,
Tin borofluoride 0.1 mol / l, thiourea 1.0 mol / l, temperature
A Cu-Sn substitution reaction was performed under the conditions of 50 ° C. and pH = 1.2 to provide a 0.3 μm thick Sn layer on the surface of the roughened layer 11 (the Sn layer is not shown).

(11) By repeating the above steps (2) to (10), a further upper layer conductive circuit was formed, and a multilayer printed wiring board was obtained. However, Sn substitution was not performed (FIGS. 18 to 23).
reference). (12) Further, the steps (17) to (20) of Example 1 were performed to manufacture a multilayer printed wiring board having the solder bumps 17 (see FIG. 24).

Comparative Example 2 Multilayer printed wiring was performed in the same manner as in Example 2 except that the adhesive having the following composition was used as the adhesive for electroless plating for the upper layer constituting the interlayer resin insulating layer. Boards were manufactured. 35% by weight of 25% acrylate of cresol novolak type epoxy resin (manufactured by Nippon Kayaku, molecular weight 2500), polyether sulfone (PE
S) 12 parts by weight, imidazole curing agent (Shikoku Chemicals, 2E4M
Z-CN) 2 parts by weight, photosensitive monomer (Toa Gosei Co., Aronix M315) 4 parts by weight, photoinitiator (Ciba Geigy,
2 parts by weight of Irgacure I-907) and 0.2 part by weight of a photosensitizer (DETX-S, manufactured by Nippon Kayaku) were mixed, and the average particle size of epoxy resin particles (Polymer Pole, manufactured by Sanyo Chemical Industries) was added to the mixture. 7.2 parts by weight of diameter 1.0 μm, average particle diameter 0.5 μ
m, 3.09 parts by weight, an antifoaming agent (manufactured by San Nopco, S-6
5) After mixing 0.5 parts by weight, the mixture was further mixed while adding 30 parts by weight of NMP to obtain a photosensitive adhesive for electroless plating having a viscosity of 7 Pa · s.

This photosensitive electroless plating adhesive was heated at 25 ° C.
When stored for one month, the resin cured and could not be applied.

[0071]

As described above, according to the present invention, it is possible to suppress the hardening of the adhesive which is inevitably generated during the storage of the adhesive, so that the adhesive for electroless plating can be stored for a long time. Become. Moreover, according to the present invention, since the adhesive for electroless plating ensuring predetermined physical properties such as viscosity can be reliably provided for the production of printed wiring boards, the method for preparing the adhesive for electroless plating is suitable for mass production. It is a thing.

[Brief description of the drawings]

FIG. 1 is a view showing each manufacturing process of a multilayer printed wiring board in an example.

FIG. 2 is a diagram showing each manufacturing process of a multilayer printed wiring board in an example.

FIG. 3 is a diagram showing each manufacturing process of the multilayer printed wiring board in the example.

FIG. 4 is a view showing each manufacturing process of the multilayer printed wiring board in the example.

FIG. 5 is a diagram showing each manufacturing process of the multilayer printed wiring board in the example.

FIG. 6 is a diagram showing each manufacturing process of the multilayer printed wiring board in the example.

FIG. 7 is a diagram showing each manufacturing process of the multilayer printed wiring board in the example.

FIG. 8 is a diagram showing each manufacturing process of the multilayer printed wiring board in the example.

FIG. 9 is a diagram showing each manufacturing process of the multilayer printed wiring board in the example.

FIG. 10 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in the example.

FIG. 11 is a diagram showing each manufacturing process of the multilayer printed wiring board in Example.

FIG. 12 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in the example.

FIG. 13 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in the example.

FIG. 14 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in the example.

FIG. 15 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 16 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 17 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 18 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 19 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 20 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 21 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 22 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 23 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

FIG. 24 is a diagram illustrating each manufacturing process of the multilayer printed wiring board in Example.

[Explanation of symbols]

 Reference Signs List 1 substrate 2 interlayer resin insulating layer 2a insulating layer 2b adhesive layer 3 plating resist 4 inner layer conductor circuit (inner layer copper pattern) 5 outer layer conductor circuit (outer layer copper pattern) 6 opening for via hole 7 via hole (BVH) 8 copper foil 9 Through hole 10 Filling resin (resin filler) 12 Electroless copper plating film 13 Electrolytic copper plating film 14 Solder resist layer 15 Nickel plating layer 16 Gold plating layer 17 Solder bump

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI H05K 3/46 H05K 3/46 E N T // H05K 3/18 3/18 E (56) References JP-A-7-34048 (JP, A) JP-A-8-64961 (JP, A) JP-A-61-83218 (JP, A) JP-A-8-48964 (JP, A) JP-A-10-310687 (JP, A) ( 58) Field surveyed (Int.Cl. ⁷ , DB name) C09J 201/00 C23C 18/20 C23C 18/26 C23C 18/31 H05K 3/38 H05K 3/46 H05K 3/18

Claims (6)

(57) [Claims] 1. Each composition prepared in advance into the following form: A resin composition containing an uncured thermosetting resin which becomes hardly soluble in an acid or an oxidizing agent by a curing treatment; A resin composition containing heat-resistant resin particles which have been subjected to a curing treatment soluble in an acid or an oxidizing agent, a thermoplastic resin and an organic solvent; A hardening agent composition is prepared so as to be mixable, and a resin composition and a resin, respectively.
Composition, curing agent composition ,
Immediately before use as an adhesive for electrolytic plating
Mix and stir each of the above compositions
Adhesive for electroless plating raw material composition for the preparation obtained by the so that. 2. The raw material composition for preparing an adhesive for electroless plating according to claim 1, wherein the thermosetting resin has a part of the thermosetting functional group substituted by a photosensitive group. 3. The raw material composition for preparing an adhesive for electroless plating according to claim 1, wherein the curing agent composition contains a curing agent for a thermosetting resin and a photoinitiator. 4. An acid or oxidizing agent in a composite resin matrix comprising an uncured thermosetting resin, a thermoplastic resin, a curing agent composition and an organic solvent, which becomes hardly soluble in an acid or an oxidizing agent by a curing treatment. In preparing an adhesive for electroless plating in which soluble hardened heat-resistant resin particles are dispersed, A resin composition containing an uncured thermosetting resin which becomes hardly soluble in an acid or an oxidizing agent by a curing treatment; A resin composition containing heat-resistant resin particles which have been subjected to a curing treatment soluble in an acid or an oxidizing agent, a thermoplastic resin and an organic solvent; A curing agent composition, a resin composition, a resin composition, and a curing composition , respectively .
A method for preparing an adhesive for electroless plating, comprising mixing and stirring each of the above-mentioned isolated compositions immediately before use as an adhesive for electroless plating. 5. The electroless resin according to claim 4, wherein the thermosetting resin has a part of the thermosetting functional group substituted by a photosensitive group.
Preparation of adhesive for plating . 6. The preparation method according to claim 4, wherein the curing agent composition contains a curing agent for a thermosetting resin and a photoinitiator.