JP2003101221A - Method for manufacturing multilayer printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a multilayer printed wiring board which has a conductor circuit in which a roughed surface is formed on the overall surface without undercut with a uniform thickness and in which no crack resultantly occurs in a resin insulating layer and no release occurs between the insulating layer and the circuit. SOLUTION: The method for manufacturing the multilayer printed circuit substrate comprises (1) a step of forming a thin film conductor layer 24 on the substrate and/or on the resin insulating layer 22, (2) a step of forming a thicker electrically plating layer 25 than the plating resist on the plating resist non-forming part after the plating resist 23 is formed by using the dry film on the part of the layer 2, (3) a step of etching the plating layer by using a first etching liquid, and (4) a step of removing the layer 24 existing under the resist 23 by using a second etching liquid after the resist 23 is removed and forming roughed surfaces on the surface of the layer 25 and the side face of the layer 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a multilayer printed wiring board.

[0002]

2. Description of the Related Art Conventionally, build-up multilayer printed wiring boards have been manufactured by the method disclosed in, for example, Japanese Patent Laid-Open No. 4-55555. That is, first, a through hole is formed in a copper clad laminate to which a copper foil is attached, and then a through hole is formed by performing an electroless copper plating process. Then, the surface of the substrate is etched into a conductor pattern to form a conductor circuit, and on the surface of the conductor circuit,
A roughened surface is formed by etching or the like. Then, after forming a resin insulating layer on the conductor circuit having this roughened surface, exposure and development processing is performed to form an opening for a via hole, and then UV curing and main curing are performed to form an interlayer resin insulating layer. To do.

Further, after roughening the interlayer resin insulation layer with an acid or an oxidizing agent, a thin electroless plating layer is formed, and a plating resist is formed on the electroless plating layer.
After thickening by electroplating and removing the plating resist, an independent conductor circuit is formed by removing the thin electroless plating layer existing under the plating resist with an etching solution. A roughened surface is formed on the conductor circuit surface with an acid salt or the like. After repeating this process, finally, a solder resist layer for protecting the conductor circuit is formed, an opening is formed for connection with an IC chip, etc., the exposed conductor circuit is plated, and solder paste is applied. The manufacturing of the build-up multilayer printed wiring board is completed by printing and forming solder bumps.

However, when the build-up multilayer printed wiring board is manufactured by such a method, if the thin electroless plating layer existing under the plating resist is removed by an etching solution, a part of the thickened electroplating layer is removed. Since it is also removed, there is a problem that the electroplating layer becomes thin. Further, when etching is performed to form a roughened surface, the side surface of the conductor circuit may be excessively etched, resulting in an undercut shape, or unevenness on the roughened surface of the undercut portion may be small. . Therefore, when the interlayer resin insulation layer is formed on the conductor circuit, the undercut portion is not filled with resin, or the adhesion between the undercut portion and the resin is low, and cracks occur in the interlayer resin insulation layer. In addition, there is a problem that the interlayer resin insulation layer and the conductor circuit are peeled off.

[Problems to be Solved by the Invention]

Therefore, in order to avoid such a problem, there is also a method of forming a thick and wide electroplating layer when performing thickening by electroplating. However, in this case, the following problems occur. That is, when the electroplating layer is formed thickly, as shown in FIG. 17, the thin film conductor layer 24 is formed on the resin insulating layer 22 (see FIG. 17A), and then on the thin film conductor layer 24. After the plating resist 23 is formed (see FIG. 17B), the electroplating layer 25 is formed to be thicker than the thickness of the plating resist 23 (see FIG. 17C). As a result, the electroplating layer 25
Is formed up to the top of the plating resist 23, and when the plating resist 23 is peeled off, the plating resist 23 cannot be completely peeled off, and the plating resist residue 23a exists on a part of the side surface of the electroplating layer 25. (Figure 1
7 (d)).

Therefore, the thin film conductor layer existing under the plating resist 23 should be removed (see FIG. 17 (e)), and a roughened surface should be formed on the surface of the electroplating layer 23 and the side surface of the thin film conductor layer 24. In that case, the plating resist residue 23a is present, and a portion where the roughened surface is not formed is generated (see FIG. 17 (f)). In this way, if there is a portion where the roughened surface is not formed, the adhesion between the conductor circuit and the resin insulating layer becomes insufficient at this portion, which causes separation between the interlayer resin insulating layer and the conductor circuit. .

When the electroplating layer 25 is formed thicker than the thickness of the plating resist 23, the upper surface of the electroplating layer 25 is not flat, so that the thickness of the electroplating layer 25 is not uniform when it is formed as an independent conductor circuit. There is also the problem of becoming uniform. As described above, when the thickness of the conductor circuit is not uniform, the obtained multilayer printed wiring board has poor electrical characteristics.

Further, when the electroplating layer is formed wide, the distance between the conductor circuits becomes narrower by that amount. Therefore, after removing the plating resist, the thin film conductor layer existing under the plating resist should be removed. In that case, the etching solution may not sufficiently enter between the conductor circuits.
In such a case, a part of the thin film conductor layer that is not removed occurs, which causes a short circuit between the conductor circuits.

Further, when the electroplating layer is formed, if the electroplating layer is formed thick so that the electroplating layer is not formed on the plating resist even if the electroplating layer is thickened, the plating resist becomes thick, The depth of the plating resist non-formed portion becomes deep, and as a result, a portion where the electroplating layer cannot be formed occurs in a part of the plating resist non-formed portion.

The present invention has been made to solve the above problems, and an object thereof is to provide a conductor circuit having a uniform thickness, no undercut, etc., and a roughened surface formed on the entire surface. Then, as a result, it is an object of the present invention to provide a method for manufacturing a multilayer printed wiring board in which cracks do not occur in the interlayer resin insulating layer and peeling does not occur between the interlayer resin insulating layer and the conductor circuit.

[0011]

Means for Solving the Problems As a result of intensive studies aimed at achieving the above object, the present inventors have found that an electroplating layer on a plating resist is formed by performing a first etching treatment before peeling the plating resist. And the thickness of the electroplating layer is almost the same as the thickness of the plating resist,
Then, after the plating resist is peeled off, a second etching process and a roughened surface forming process are performed to form a conductor circuit having a uniform thickness, no undercut, and a roughened surface on the entire surface. It was found that the above-mentioned multilayer printed wiring board can be manufactured, and an invention having the following contents as a gist constitution was reached.

That is, the method for manufacturing a multilayer printed wiring board according to the present invention is a multilayer printed wiring board in which a conductor circuit and a resin insulating layer are sequentially formed on a substrate and these conductor circuits are connected through via holes. The manufacturing method of the above is characterized by including the following steps (1) to (4). (1) a step of forming a thin film conductor layer on the substrate and / or the resin insulating layer, (2) after forming a plating resist using a dry film on a part of the thin film conductor layer, and then the plating resist A step of forming an electroplating layer thicker than the thickness of the plating resist on the non-formation portion, (3)
A step of etching the electroplating layer with a first etching solution, and (4) removing the plating resist, and then using a second etching solution to remove a thin film conductor layer existing under the plating resist. A step of removing and forming a roughened surface on the surface of the electroplating layer and the side surface of the thin film conductor layer.

In the manufacturing method of the present invention, the first etching solution is at least one selected from the group consisting of cupric chloride, ferric chloride, persulfate, hydrogen peroxide / sulfuric acid, and alkaline etchant. It is desirable that the solution contains.

The first etching solution is preferably a mixed solution containing a cupric complex and an organic acid salt, or a mixed solution containing hydrogen peroxide and sulfuric acid.

In the above manufacturing method, the second etching solution is preferably a mixed solution containing a cupric complex and an organic acid salt, or a mixed solution containing hydrogen peroxide and sulfuric acid.

In the above manufacturing method, the first etching solution and the second etching solution are a mixed solution containing a cupric complex and an organic acid salt or a mixed solution containing hydrogen peroxide and sulfuric acid. It is desirable that the first etching liquid and the second etching liquid are the same.

Further, in the above manufacturing method, the above (3)
In the step (1), it is desirable to perform buffing after etching the electroplating layer using the first etching liquid.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A method for manufacturing a multilayer printed wiring board according to the present invention is a multilayer printed board in which a conductor circuit and a resin insulating layer are sequentially formed on a substrate, and these conductor circuits are connected through via holes. A method of manufacturing a wiring board is characterized by including the following steps (1) to (4). (1) a step of forming a thin film conductor layer on the substrate and / or the resin insulating layer, (2) after forming a plating resist using a dry film on a part of the thin film conductor layer, and then the plating resist A step of forming an electroplating layer thicker than the thickness of the plating resist on the non-formation portion, (3)
A step of etching the electroplating layer with a first etching solution, and (4) removing the plating resist, and then using a second etching solution to remove a thin film conductor layer existing under the plating resist. A step of removing and forming a roughened surface on the surface of the electroplating layer and the side surface of the thin film conductor layer.

According to the above-mentioned method for manufacturing a multilayer printed wiring board, since the first etching treatment is performed before the plating resist is peeled off, the electroplating layer formed thicker than the thickness of the plating resist and the upper portion of the plating resist are formed. The formed electroplating layer is removed and its thickness becomes uniform. As a result, if the plating resist is peeled off after this step, the plating resist is completely peeled off, and the plating resist residue does not exist on the side surface of the conductor circuit. In the present invention, since the second etching treatment is performed and the roughened surface formation treatment is performed after the plating resist is peeled off,
It is possible to manufacture a multilayer printed wiring board having a uniform thickness and no undercut, and a conductor circuit having a roughened surface formed on the surface. In the multilayer printed wiring board manufactured by such a manufacturing method, Since the conductor circuit having the above characteristics is formed, the resin insulating layer adheres to the conductor circuit, and the via hole also adheres to the conductor circuit below. As a result, the multilayer printed wiring board has excellent connectivity and reliability.

FIG. 1 is a sectional view showing an example of a step of forming a conductor circuit on a resin insulating layer in the manufacturing method of the present invention. In the manufacturing method of the present invention, as shown in FIG. 1, first, the thin film conductor layer 24 is formed on the resin insulating layer 22 (see FIG. 1A). The resin insulation layer means, for example, an interlayer resin insulation layer.

As the material of the thin film conductor layer 24, for example,
Examples thereof include tin, zinc, copper, nickel, cobalt, thallium and lead. Among these, copper is preferable in consideration of electrical characteristics, economy, and the like. Examples of the method for forming the thin film conductor layer 24 include sputtering, electroless plating, vapor deposition and the like. The thickness of the thin film conductor layer 24 is
0.3 to 2.0 μm is desirable. The thickness is 0.3 μm
When the thickness is less than 1.0 μm, the thin film conductor layer may not be able to follow the shape of the roughened surface when the roughened surface is formed on the surface of the resin insulating layer. This is because the thin film conductor layer cannot be completely removed when removing the conductor layer, which may cause a short circuit. The material of the resin insulation layer will be described later.

Next, a plating resist 23 is formed on a part of the thin film conductor layer 24 by using a dry film (see FIG. 1).
(See (b)). As a method for forming the plating resist 23, for example, a photosensitive dry film is used as the thin film conductor layer 24.
Examples of the method include a method of removing the plating resist non-formation portion by performing exposure and development treatment after the film is pasted on. The dry film is not particularly limited, and examples thereof include a commercially available photosensitive dry film and the like. Plating resist 2
The thickness of 3 is not particularly limited and may be appropriately selected in consideration of the thickness of the conductor circuit to be formed, etc.
30 μm is desirable.

Next, an electroplating layer 25 is formed on the thin film conductor layer 24 on the portion where the plating resist 23 is not formed. As shown in FIG. 1C, the electroplating layer 25 is formed on the plating resist 2
It is formed thicker than the thickness of 3. This is the electroplating layer 2
By forming 5 thickly, when conducting a later-described etching process to form a conductor circuit having a roughened surface,
This is because the conductor circuit can be formed in a desired shape without becoming too thin. At this time, the electroplating layer 25 may be formed up to the upper part of the plating resist 23.

Subsequently, the surface layer portion of the electroplating layer 25 is removed using the first etching solution (see FIG. 1 (d)). In this case, the side surface of the electroplating layer 25 has the plating resist 23.
Since it is in contact with the first etching solution, it is not removed by the first etching solution, and only the surface layer portion of the electroplated layer 25 is removed by the first etching solution. for that reason,
By performing this step, the electroplating layer 25 formed on the plating resist 23 is removed, and
The upper surface of the electroplated layer 25 is flattened, and the electroplated layer 25 having a uniform thickness can be formed.

After removing the surface layer portion of the electroplating layer 25 using the first etching solution, the buffing of the upper surface of the electroplating layer 25 may be performed. In particular, when the surface layer portion of the electroplating layer 25 is removed by using the first etching solution described above, when etching is not performed for a long time or etching is performed by using a low concentration etching solution, the buffing is performed. You may grind.

This is because, in order to prevent the thickly formed electroplating layer from being thinned by etching, when the etching conditions are moderated, the electroplating layer may slightly remain above the plating resist 23. This is because, in this case, by removing the electroplating layer remaining on the upper portion of the plating resist 23 by buffing, the plating resist 23 can be reliably removed in a subsequent step.

Examples of the first etching solution include cupric chloride, ferric chloride, persulfate, hydrogen peroxide /
Sulfuric acid, alkali etchant, etc. may be mentioned. These first etching solutions may be used alone or in combination of two or more. With such an etching solution,
When performing the first etching process, the thickness of the electroplated layer is secured by performing the etching process in a short time using an etching solution having a relatively low concentration. Then, after the etching process is completed, buffing is performed to flatten the upper surface of the electroplating layer to some extent, and when a residue of the electroplating layer is present on the upper portion of the plating resist, it may be removed. . Specific conditions for performing the first etching treatment using the above etching solution may be appropriately selected in consideration of the thickness of the electroplating layer, the type of metal forming the electroplating layer, and the like.

As the first etching solution,
For example, a mixed solution containing a cupric complex and an organic acid salt, a mixed solution containing hydrogen peroxide and sulfuric acid, or the like may be used. When a mixed solution containing a cupric complex and an organic acid salt or a mixed solution containing hydrogen peroxide and sulfuric acid is used as the first etching solution, as shown in FIG. It is possible to remove the surface layer portion of the electroplating layer 25 and form the roughened surface 25a on the upper surface of the conductor circuit. Therefore, when an independent conductor circuit is formed through the steps described below, the conductor circuit has a roughened surface with sufficient roughness.

The cupric complex is not particularly limited, but cuprous complexes of azoles are preferable. This type of cupric complex acts as an oxidizing agent that oxidizes metallic copper and the like.
As the azoles, diazole, triazole,
Tetrazole is preferred. Among them, imidazole, 2
-Methylimidazole, 2-ethylimidazole, 2-
Ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole and the like are desirable. The addition amount of the cupric complex is preferably 1 to 15% by weight.
This is because when the amount added is in the above range, the solubility and stability of the cupric complex are excellent.

The organic acid is blended with the cupric complex to dissolve copper oxide. When a cupric complex of an azole is used, the organic acid is formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, acrylic acid,
At least one selected from the group consisting of crotonic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, maleic acid, benzoic acid, glycolic acid, lactic acid, malic acid and sulfamic acid is desirable. The content of organic acid is 0.1
-30% by weight is preferred. This is for maintaining the solubility of the oxidized copper and ensuring the dissolution stability.

To the mixed solution containing the cupric complex and the organic acid salt, halogen ions such as fluorine ion, chlorine ion and bromine ion are added in order to assist the dissolution of copper and the oxidation action of azoles. Good. The halogen ions can be supplied as hydrochloric acid, sodium chloride or the like. The amount of halogen ions added is preferably 0.01 to 20% by weight. This is because it is possible to form a roughened surface having excellent adhesion to the interlayer resin insulation layer.

The mixed solution containing the cupric complex and the organic acid salt can be prepared by dissolving the cupric complex, the organic acid, and optionally a halogen ion in water. Further, a commercially available product manufactured by Mec Co., Ltd. under the trade name of "Mech Etch Bond" can be used. Further, the mixed solution containing the cupric complex and the organic acid salt and the mixed solution containing hydrogen peroxide and sulfuric acid may contain an additive or a stabilizer.

Next, the plating resist 23 is peeled off (see FIG.
(See (e)), and then using the second etching solution, the thin film conductor layer 24 existing under the plating resist 23 is removed and the surface of the electroplating layer 25 and the thin film conductor layer 2 are removed.
A roughened surface 25a and a roughened surface 24a are formed on the four side surfaces (see FIG. 1 (f)).

Examples of the second etching solution include a mixed solution containing a cupric complex and an organic acid salt, a mixed solution containing hydrogen peroxide and sulfuric acid, and the like. Which etching solution is used as the second etching solution is preferably selected in consideration of the first etching solution, and specifically, as the first etching solution and the second etching solution, It is desirable to use the same etching solution.

Through these steps, it is possible to form a conductor circuit having a roughened surface on the resin insulating layer. Although the method for forming the conductor circuit on the resin insulating layer has been described with reference to FIG. 1, the same method can be used for forming the conductor circuit on the substrate.

Next, the method for manufacturing a printed wiring board of the present invention will be described in the order of steps. (1) In the method for producing a printed wiring board of the present invention, first, a substrate having a conductor circuit formed on the surface of an insulating substrate is produced.

As the insulating substrate, a resin substrate is desirable, and specifically, for example, a glass epoxy substrate, a polyester substrate, a polyimide substrate, a bismaleimide-triazine resin substrate, a thermosetting polyphenylene ether substrate, a fluororesin substrate, Ceramic substrate, copper clad laminate, R
Examples include CC substrates. At this time, a through hole may be provided in this insulating substrate. In this case, the through hole has a diameter of 10
It is desirable to use a drill of 0 to 300 μm, a laser beam, or the like.

(2) Next, using the method as described above,
Conductor circuits are formed on the substrate. That is, a thin film conductor layer is formed on a substrate by electroless plating, a plating resist is formed on a part of the thin film conductor layer, and then an electroplating layer is formed on a plating resist non-forming portion. Subsequently, the electroplating layer surface layer portion is removed using the first etching solution, and the plating resist is peeled off, and then the thin film conductor existing under the plating resist is used using the second etching solution. The layer is removed, and a roughened surface is formed on the surface of the electroplated layer and the side surface of the thin film conductor layer.

Copper plating is desirable as the electroless plating. Further, the average roughness Rz of the roughened surface formed at this time
Is preferably 0.1 to 5 μm. Furthermore, considering the adhesion between the conductor circuit and the interlayer resin insulation layer, the easiness of etching of the metal layer, and the like, the thickness is more preferably 2 to 4 μm. Further, in the case where the through hole is provided in the insulating substrate, when the thin film conductor layer is formed, the wall surface of the through hole is also electroless plated at the same time to form the through hole. The conductor circuits may be electrically connected.

Further, instead of the above method, the following method may be used to form the conductor circuit on the substrate. That is, a copper clad substrate is used, or electroless plating is performed on the substrate to form a solid conductor layer, then a conductor circuit-shaped etching resist is formed on the substrate, and etching is performed to form a conductor circuit. May be.

After the electroless plating, a roughening treatment is usually performed on the surface of the electroless plating layer and the inner wall of the through hole when the through hole is formed. Examples of the roughening formation treatment method include blackening (oxidation) -reduction treatment, spray treatment with a mixed aqueous solution of an organic acid and a cupric complex, and Cu.
-Ni-P needle-like alloy plating may be used.

As a concrete method of the above blackening (oxidation) -reduction treatment, NaOH (10 g / l), NaClO ₂
(40 g / l), a blackening treatment using an aqueous solution containing Na ₃ PO ₄ (6 g / l) as a blackening bath (oxidizing bath), and NaO
Examples thereof include a method of performing reduction treatment using an aqueous solution containing H (10 g / l) and NaBH ₄ (6 g / l) as a reducing bath.

(3) Next, an interlayer resin insulation layer is formed on the substrate on which the conductor circuit is formed. Examples of the material for the interlayer resin insulating layer include a resin composition for forming a roughened surface, a polyphenylene ether resin, a polyolefin resin, a fluororesin, and a thermoplastic elastomer. The interlayer resin insulation layer may be formed by applying an uncured resin,
It may be formed by thermocompression bonding an uncured resin film. Further, a resin film having a metal layer such as a copper foil formed on one surface of the uncured resin film may be attached.

Examples of the resin composition for forming a roughened surface include a resin in which particles soluble in an acid or an oxidizing agent (hereinafter referred to as soluble particles) are hardly soluble in an acid or an oxidizing agent (hereinafter referred to as a poorly soluble resin). The thing dispersed in is mentioned. It should be noted that the terms "poorly soluble" and "soluble" are referred to as "soluble" for the sake of convenience, and those having a relatively high dissolution rate when immersed in the same roughening solution for the same time are referred to as "relatively soluble". The slow one is called "poorly soluble" for convenience.

Examples of the soluble particles include resin particles soluble in an acid or an oxidizing agent (hereinafter, soluble resin particles), inorganic particles soluble in an acid or an oxidizing agent (hereinafter, soluble inorganic particles), acid or an oxidizing agent. Examples thereof include soluble metal particles (hereinafter, soluble metal particles). These soluble particles may be used alone or in combination of two or more kinds.

The shape (particle size, etc.) of the soluble particles is not particularly limited, but (a) soluble particles having an average particle size of 10 μm or less and (b) aggregating soluble particles having an average particle size of 2 μm or less are aggregated. Particles, (c) average particle size 2 to 10 μm
Mixture of soluble particles having a mean particle size of 2 μm or less, and (d) a heat-resistant resin powder having a mean particle size of 2 μm or less or an inorganic powder on the surface of the soluble particles having a mean particle size of 2 to 10 μm. (F) a mixture of soluble particles having an average particle size of 0.1 to 0.8 μm and soluble particles having an average particle size of more than 0.8 μm and less than 2 μm, (f) ) Average particle size is 0.1 to 1.0 μm
It is desirable to use soluble particles of This is because they can form more complex anchors.

Examples of the soluble resin particles include those made of a thermosetting resin, a thermoplastic resin, etc., which have a faster dissolution rate than the hardly soluble resin when immersed in a solution containing an acid or an oxidizing agent. It is not particularly limited as long as it is. Specific examples of the soluble resin particles, for example, those made of epoxy resin, phenol resin, polyimide resin, polyphenylene resin, polyolefin resin, fluororesin, amino resin (melamine resin, urea resin, guanamine resin) and the like, It may be one of these resins or a mixture of two or more resins.

As the soluble resin particles, resin particles made of rubber can be used. Examples of the rubber include polybutadiene rubber, various modified polybutadiene rubbers such as epoxy-modified, urethane-modified, (meth) acrylonitrile-modified, and (meth) acrylonitrile-butadiene rubber containing a carboxyl group. By using these rubbers, the soluble resin particles are easily dissolved in the acid or the oxidizing agent. That is, when dissolving soluble resin particles using an acid, it is possible to dissolve an acid other than a strong acid, and when dissolving soluble resin particles using an oxidizing agent, permanganese, which has a relatively weak oxidizing power, is dissolved. It can be dissolved in acid. Even when chromic acid is used, it can be dissolved at a low concentration. for that reason,
No acid or oxidant remains on the resin surface, and as described later, when a catalyst such as palladium chloride is applied after the roughened surface is formed, the catalyst is not applied or the catalyst is oxidized. There is no.

Examples of the soluble inorganic particles include particles made of at least one selected from the group consisting of aluminum compounds, calcium compounds, potassium compounds, magnesium compounds and silicon compounds.

Examples of the aluminum compound include alumina and aluminum hydroxide, and examples of the calcium compound include calcium carbonate and
Examples thereof include calcium hydroxide and the like, examples of the potassium compound include potassium carbonate and the like, examples of the magnesium compound include magnesia, dolomite, basic magnesium carbonate and the like, and examples of the silicon compound include: Examples thereof include silica and zeolite. These may be used alone or in combination of two or more.

Examples of the soluble metal particles include, for example,
Copper, nickel, iron, zinc, lead, gold, silver, aluminum,
Examples thereof include particles made of at least one selected from the group consisting of magnesium, calcium and silicon. The surface layer of these soluble metal particles may be coated with a resin or the like in order to ensure insulation.

When two or more kinds of the above-mentioned soluble particles are mixed and used, the combination of the two kinds of soluble particles to be mixed is preferably a combination of resin particles and inorganic particles. Both can ensure the insulation of the resin film because the conductivity is low, it is easy to adjust the thermal expansion with the poorly soluble resin, cracks do not occur in the interlayer resin insulation layer made of the resin film, This is because peeling does not occur between the interlayer resin insulation layer and the conductor circuit.

The sparingly soluble resin is not particularly limited as long as it can maintain the shape of the roughened surface when the roughened surface is formed in the interlayer resin insulating layer using an acid or an oxidizing agent. Examples thereof include thermosetting resins, thermoplastic resins, and composites thereof. Further, it may be a photosensitive resin obtained by imparting photosensitivity to these resins. Among these, those containing a thermosetting resin are desirable. This is because the shape of the roughened surface can be maintained by the plating solution or various heat treatments.

Examples of the thermosetting resin include epoxy resin, phenol resin, polyimide resin and the like. Examples of the sensitized resin include those obtained by subjecting methacrylic acid, acrylic acid and the like to an acrylation reaction with a thermosetting group. . In particular, an acrylated epoxy resin is desirable. Among these, an epoxy resin having two or more epoxy groups in one molecule is more desirable. Not only can the roughened surface described above be formed, but because it is also excellent in heat resistance, etc., stress concentration does not occur in the metal layer even under heat cycle conditions,
This is because peeling of the metal layer is unlikely to occur.

Examples of the epoxy resin include cresol novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, alkylphenol novolac type epoxy resin, biphenol F type epoxy resin, naphthalene type epoxy resin. Resin, dicyclopentadiene type epoxy resin, epoxidized product of a condensation product of a phenol and an aromatic aldehyde having a phenolic hydroxyl group,
Examples thereof include triglycidyl isocyanurate and alicyclic epoxy resin. These may be used alone or in combination of two or more. As a result, the heat resistance is excellent.

Examples of the thermoplastic resin include polyether sulfone (PES) and polysulfone (PS).
F), polyphenylene sulfone (PPS), polyphenylene sulfide (PPES), polyphenylene ether (PPE), polyetherimide (PI), fluororesin, phenoxy resin and the like.

The mixing ratio of the thermosetting resin and the thermoplastic resin is as follows: thermosetting resin / thermoplastic resin = 95/5 to 50
/ 50 is desirable. This is because a high toughness value can be secured without impairing heat resistance.

The mixing weight ratio of the above soluble particles is preferably 5 to 50% by weight, based on the solid content of the poorly soluble resin, and 10 to 10% by weight.
40% by weight is more desirable.

When the interlayer resin insulation layer is formed by using an uncured resin film, it is desirable that the soluble particles in the resin film are substantially uniformly dispersed in the sparingly soluble resin. It is possible to form a roughened surface having unevenness with a uniform roughness, and even if a via hole or a through hole is formed in the resin film, it is possible to secure the adhesion of the metal layer of the conductor circuit formed thereon. Because you can. Moreover, you may use the resin film which contains a soluble particle only in the surface layer part which forms a roughened surface. Thereby,
Since the parts other than the surface layer of the resin film are not exposed to the acid or the oxidizing agent, the insulation between the conductor circuits via the interlayer resin insulation layer is surely maintained.

In the above resin film, the amount of soluble particles dispersed in the sparingly soluble resin is preferably 3 to 40% by weight based on the resin film. If the content of the soluble particles is less than 3% by weight, it may not be possible to form a roughened surface having desired irregularities, and if it exceeds 40% by weight, when the soluble particles are dissolved using an acid or an oxidizing agent. In addition, the resin film may be dissolved to a deep portion, and the insulation between the conductor circuits via the interlayer resin insulation layer made of the resin film cannot be maintained, which may cause a short circuit.

In addition to the soluble particles and the sparingly soluble resin, the resin film may contain a curing agent, a solvent, other components, etc., if necessary.

The polyphenylene ether resin is not particularly limited, and examples thereof include PPO and PPE. Examples of the polyolefin resin include polyethylene, polypropylene, polyisobutylene, polybutadiene, polyisoprene, cycloolefin resin,
Examples thereof include copolymers of these resins. Among them, the dielectric constant and the dielectric loss tangent are low, the signal delay and the signal error are less likely to occur even when a high frequency signal in the GHz band is used, and further, the mechanical properties such as the rigidity are excellent. Olefinic resins are desirable.

The above cycloolefin resin is 2
-Norbornene, 5-ethylidene-2-norbornene or homopolymers or copolymers of monomers composed of derivatives thereof are preferable. Examples of the derivative include 2-
Examples thereof include cycloolefins such as norbornene bonded to an amino group for forming a crosslink, a maleic anhydride residue, or a maleic acid modified product. Examples of the monomer for synthesizing the copolymer include ethylene and propylene.

The cycloolefin-based resin may be a mixture of two or more of the above-mentioned resins, and may contain a resin other than the cycloolefin-based resin. When the cycloolefin-based resin is a copolymer, it may be a block copolymer or a random copolymer.

The cycloolefin resin is preferably a thermosetting cycloolefin resin.
By heating to form crosslinks, the rigidity is further increased and the mechanical properties are improved. The glass transition temperature (Tg) of the cycloolefin resin is 13
It is preferably 0 to 200 ° C.

As the cycloolefin resin, a resin sheet (film) already formed may be used, and a monomer or a low molecular weight polymer having a constant molecular weight is a solvent such as xylene or cyclohexane. It may be in the state of an uncured solution dispersed in. In the case of a resin sheet, so-called RCC (RESIN COATE
D copper: copper foil with resin) may be used.

The cycloolefin resin may contain no filler or the like, or may contain a flame retardant such as aluminum hydroxide, magnesium hydroxide or phosphoric acid ester.

Examples of the fluororesin include ethyl / tetrafluoroethylene copolymer resin (ETFE) and polychlorotrifluoroethylene (PCTFE).

The thermoplastic elastomer resin is not particularly limited, and examples thereof include styrene-based thermoplastic elastomer, olefin-based thermoplastic elastomer, urethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, and 1,2. -Polybutadiene-based thermoplastic elastomer, vinyl chloride-based thermoplastic elastomer, fluorine-based thermoplastic elastomer and the like. Among these, olefin-based thermoplastic elastomers and fluorine-based thermoplastic elastomers are desirable from the viewpoint of excellent electrical properties.

When the interlayer resin insulating layer is formed by sticking the above resin film, the interlayer resin insulating layer is formed by using a device such as a vacuum laminator under a reduced pressure or a vacuum of 2.0 to 10 kgf / cm ² pressure,
It is desirable to carry out pressure bonding at a temperature of 60 to 120 ° C., and then thermosetting the resin film. The heat curing may be performed after the via hole opening and the through hole described below are formed.

(4) Next, a via hole opening and, if necessary, a through hole are formed in the substrate on which the interlayer resin insulation layer is formed. The via hole opening is formed by laser processing or the like. When an interlayer resin insulation layer made of a photosensitive resin is formed, exposure and development treatments are performed to
You may provide the opening for via holes. At this time, examples of the laser beam used include carbon dioxide (CO ₂ ) laser, ultraviolet laser, excimer laser, and the like. Among these, excimer laser and short pulse carbon dioxide laser are preferable.

As will be described later, the excimer laser can form a large number of openings for a via hole at a time by using a mask or the like in which a through hole is formed in a portion where an opening for a via hole is formed. This is because the short pulse carbon dioxide laser has less resin remaining in the opening and less damage to the resin around the opening.

Among the excimer lasers, it is desirable to use a hologram type excimer laser. The hologram method is a method of irradiating a target object with a laser beam through a hologram, a condenser lens, a laser mask, a transfer lens, and the like. The opening can be efficiently formed.

When using a carbon dioxide laser, the pulse interval is preferably 10 ^-4 to 10 ^-8 seconds. Further, the time for irradiating the laser for forming the opening is preferably 10 to 500 μsec. In the excimer laser, the through hole of the mask in which the through hole is formed in the portion forming the opening for the via hole needs to be a perfect circle in order to make the spot shape of the laser light a perfect circle. The diameter is preferably about 0.1 to 2 mm.

When the opening is formed by laser light, especially when a carbon dioxide laser is used, desmear treatment is preferably performed. The desmear treatment can be performed using an oxidant composed of an aqueous solution of chromic acid, permanganate, or the like. Alternatively, the treatment may be performed by oxygen plasma, mixed plasma of CF ₄ and oxygen, corona discharge, or the like. Further, the surface can be modified by irradiating ultraviolet rays using a low pressure mercury lamp. When a through hole is formed in the substrate on which the interlayer resin insulation layer is formed, the diameter is 50 to 300.
A through hole is formed using a μm drill, laser light, or the like.

(5) Next, the surface of the interlayer resin insulation layer including the inner wall of the via hole opening and the inner wall of the through hole when the through hole is formed in the above step are roughened with an acid or an oxidizing agent. To form a converted surface. Examples of the acid include sulfuric acid, nitric acid, hydrochloric acid,
Examples of the oxidizing agent include phosphoric acid and formic acid, and examples of the oxidizing agent include chromic acid, chromic sulfuric acid, and permanganate salts such as sodium permanganate.

After that, when an acid is used to form the roughened surface, an aqueous solution of alkali or the like is used, and when an oxidizer is used to form the roughened surface, a neutralizing solution is used in the via hole opening or Neutralize the inside of the through-hole. This operation removes the acid and oxidant so as not to affect the next step. The average roughness Rz of the roughened surface formed in this step is 0.1 to 5 μm.
m is desirable.

(6) Next, a catalyst is applied to the roughened surface thus formed, if necessary. Examples of the catalyst include palladium chloride and the like. At this time, in order to reliably apply the catalyst, by performing a plasma treatment of oxygen, nitrogen, etc., or a dry treatment such as a corona treatment, the residue of the acid or the oxidant is removed and the surface of the interlayer resin insulation layer is modified. By doing so, the catalyst can be surely applied, the metal deposition during electroless plating, and the adhesion of the electroless plating layer to the interlayer resin insulation layer can be improved. In particular, the bottom surface of the via hole opening can be improved. In, a great effect can be obtained.

(7) Next, a thin film conductor layer is formed on the formed interlayer resin insulation layer by the above method. Further, when the through hole is formed in the step (4), the through hole may be formed by forming a thin film conductor layer made of metal also on the inner wall surface of the through hole in this step.

When a through hole is formed in the above step (7), it is desirable to carry out the following processing steps. That is, blackening (oxidation) -reduction treatment of the surface of the electroless plating layer and the inner wall of the through hole, spray treatment with a mixed aqueous solution of an organic acid and a cupric complex, treatment with Cu-Ni-P needle-like alloy plating, etc. are used. The roughening forming process is performed. After that, the inside of the through hole is further filled with a resin filler or the like, and then the surface layer portion of the resin filler and the surface of the electroless plating layer are flattened by a polishing treatment method such as buff polishing. Further, electroless plating is performed to form an electroless plating layer on the thin film conductor layer made of metal and the surface layer portion of the resin filler which are already formed, thereby forming a lid plating layer on the through hole.

(8) Next, a plating resist is formed on a portion of the interlayer resin insulation layer using a dry film, and then electroplating is performed using the thin film conductor layer as a plating lead to form no plating resist. An electroplating layer thicker than the thickness of the plating resist is formed on the portion. Copper plating is preferably used as the electroplating. At this time, the via hole opening may be filled with electroplating to form a field via structure, or after filling the via hole opening with a conductive paste or the like, a lid plating layer may be formed thereon to form a field via structure. Good. By forming the field via structure, the via hole can be provided immediately above the via hole.

(9) After forming the electroplating layer, the surface layer portion of the electroplating layer is removed by using the first etching solution described above. Then, if necessary, buffing is performed on the upper surface of the electroplating layer. Then, the plating resist is peeled off, and the thin film conductor layer existing under the plating resist is removed by a second etching solution, and a roughened surface is formed on the electroplating layer surface and the thin film conductor layer side surface. , An independent conductor circuit having a roughened surface. Furthermore, if necessary, an acid or an oxidizing agent may be used to remove the catalyst on the interlayer resin insulation layer. By removing the catalyst, the metal such as palladium used for the catalyst disappears, and thus it is possible to prevent the reduction of the electrical characteristics.

(10) Thereafter, if necessary, the steps (3) to (9) are repeated, and thereafter, when it is necessary to form a roughened surface on the uppermost conductor circuit, the above-mentioned second step is carried out. An etching solution is used to form a conductor circuit having a roughened surface.

(11) Next, a solder resist layer is formed on the surface of the substrate including the uppermost conductor circuit. As the solder resist layer, for example, polyphenylene ether resin,
Examples include polyolefin resins, fluororesins, thermoplastic elastomers, solder resist resin compositions and the like. The solder resist layer is a laser treatment after applying an uncured resin (resin composition) by a roll coater method or thermocompression-bonding an uncured resin film,
It is formed by performing an opening process such as an exposure process and a developing process, and further performing a curing process.

Examples of the polyphenylene ether resin, polyolefin resin, fluororesin and thermoplastic elastomer include the same ones as those used for forming the interlayer resin insulation layer. Examples of the solder resist resin composition include (meth) acrylate of novolac type epoxy resin, imidazole curing agent, bifunctional (meth) acrylic acid ester monomer,
Paste-like flow containing a polymer of (meth) acrylic acid ester having a molecular weight of about 500 to 5000, a thermosetting resin composed of bisphenol epoxy resin, a photosensitive monomer such as a polyvalent acrylic monomer, and a glycol ether solvent. The body etc. are mentioned, and the viscosity is 1-10 at 25 degreeC.
It is desirable that it is adjusted to Pa · s.

(Meth) of the above novolac type epoxy resin
Examples of the acrylate include epoxy resins obtained by reacting glycidyl ether of phenol novolac or cresol novolac with acrylic acid, methacrylic acid, or the like. The bifunctional (meth) acrylic acid ester monomer is not particularly limited, and examples thereof include various diols and esters of acrylic acid and methacrylic acid.

(12) Next, a corrosion resistant metal layer made of Ni, Au, or the like is formed in the opening of the solder resist layer by plating, sputtering, vapor deposition, or the like, and then solder paste is printed on the IC chip connection surface. Thus, solder bumps are formed, and solder balls, pins, and the like are provided on the external substrate connection surface, thus completing the manufacture of the printed wiring board.

Plasma processing using oxygen, carbon tetrachloride, or the like may be performed at appropriate times for the character printing process for forming product recognition characters and for modifying the solder resist layer. Although the above method is based on the semi-additive method, the full-additive method may be adopted.

[0089]

The present invention will be described in more detail below. (Example 1) A. Preparation of Resin Composition for Forming Roughened Surface of Upper Layer 1) Dissolve 25% acrylate of cresol novolac type epoxy resin (Nippon Kayaku Co., molecular weight: 2500) in diethylene glycol dimethyl ether (DMDG) at a concentration of 80% by weight. Resin solution 400 parts by weight, photosensitive monomer (Toagosei Co., Ltd., Aronix M325) 60
A mixed composition was prepared by placing parts by weight, 5 parts by weight of an antifoaming agent (S-65 manufactured by San Nopco Co., Ltd.) and 35 parts by weight of N-methylpyrrolidone (NMP) in a container, and mixing by stirring.

2) Polyether sulfone (PES) 80
Parts by weight, 72 parts by weight of epoxy resin particles (manufactured by Sanyo Kasei Co., Ltd., polymer pole) having an average particle size of 1.0 μm, and 31 parts by weight of particles having an average particle size of 0.5 μm are placed in another container,
After stirring and mixing, 257 parts by weight of NMP was further added,
Another mixed composition was prepared by stirring and mixing with a bead mill.

3) Imidazole curing agent (2, manufactured by Shikoku Kasei)
E4MZ-CN) 20 parts by weight, photopolymerization initiator (benzophenone) 20 parts by weight, photosensitizer (Ciba Specialty Chemicals, EAB) 4 parts by weight and NMP16.
A part by weight was further placed in another container and mixed by stirring to prepare a mixed composition. Then, the resin composition for forming a roughened surface was obtained by mixing the mixed compositions prepared in 1), 2) and 3).

B. Preparation of Resin Composition for Forming Roughened Surface of Lower Layer 1) Dissolve 25% acrylate of cresol novolac type epoxy resin (Nippon Kayaku Co., Ltd., molecular weight: 2500) in diethylene glycol dimethyl ether (DMDG) at a concentration of 80% by weight. Resin solution 400 parts by weight, photosensitive monomer (Toagosei Co., Ltd., Aronix M325) 60
A mixed composition was prepared by placing parts by weight, 5 parts by weight of an antifoaming agent (S-65 manufactured by San Nopco Co., Ltd.) and 35 parts by weight of N-methylpyrrolidone (NMP) in a container, and mixing by stirring.

2) Polyether sulfone (PES) 80
Parts and 145 parts by weight of epoxy resin particles (polymer pole manufactured by Sanyo Kasei Co., Ltd.) having an average particle size of 0.5 μm were placed in another container and mixed with stirring, and then NMP28 was added.
5 parts by weight was added and mixed by stirring with a bead mill to prepare another mixed composition.

3) Imidazole curing agent (manufactured by Shikoku Kasei Co., Ltd., 2
E4MZ-CN) 20 parts by weight, photopolymerization initiator (benzophenone) 20 parts by weight, photosensitizer (Ciba Specialty Chemicals, EAB) 4 parts by weight and NMP16.
A part by weight was further placed in another container and mixed by stirring to prepare a mixed composition. Then, the mixed composition prepared in 1), 2) and 3) was mixed to obtain an adhesive for electroless plating.

C. Preparation of Resin Filler 1) 100 parts by weight of bisphenol F type epoxy monomer (Made by Yuka Shell Co., molecular weight: 310, YL983U), the surface of which is coated with a silane coupling agent has an average particle diameter of 1.6 μm and maximum particles. With a diameter of 15 μm or less
iO ₂ spherical particles (manufactured by Adtech, CRS 1101-
170 parts by weight of CE) and 1.5 parts by weight of a leveling agent (Perenol S4 manufactured by San Nopco Co.) were placed in a container and mixed by stirring to have a viscosity of 45 to 4 at 23 ± 1 ° C.
A resin filler of 9 Pa · s was prepared. As a curing agent, an imidazole curing agent (2E4MZ-manufactured by Shikoku Kasei Co., Ltd.
(CN) 6.5 parts by weight was used.

D. Manufacturing method of printed wiring board (1) 0.8mm thick glass epoxy resin or BT
A copper clad laminate having 18 μm copper foil 8 laminated on both sides of a substrate 1 made of (bismaleimide triazine) resin was used as a starting material (see FIG. 2A). First, this copper clad laminate was drilled, electroless plated, and patterned to form lower conductor circuits 4 and through holes 9 on both sides of the substrate 1.

(2) Through hole 9 and lower conductor circuit 4
After washing the substrate on which water has been formed and drying it, NaOH (1
0 g / l), NaClO ₂ (40 g / l), Na ₃ PO
Blackening treatment using an aqueous solution containing ₄ (16 g / l) as a blackening bath (oxidizing bath), and NaOH (19 g / l), NaB
A reduction treatment was performed using an aqueous solution containing H ₄ (5 g / l) as a reduction bath, and roughened surfaces 4a and 9a were formed on the entire surface of the lower conductor circuit 4 including the through holes 9 (see FIG. 2 (b)). ).

(3) After the resin filler described in C above is prepared, the conductor circuit non-formation portion and the conductor circuit in the through hole 9 and on one surface of the substrate 1 and the conductor circuit are prepared within 24 hours after the preparation by the following method. A layer of the resin filler 10 was formed on the outer edge portion of No. 4. That is, first, a resin filler was pushed into the through holes using a squeegee, and then dried at 100 ° C. for 20 minutes. Next, a mask having an opening corresponding to the conductor circuit non-formation portion is placed on the substrate, and a layer of the resin filler 10 is formed on the conductor circuit non-formation portion, which is the concave portion, using a squeegee. It was dried at 20 ° C. for 20 minutes (see FIG. 2 (c)).

(4) The surface of the inner layer copper pattern 4 and the through hole 9 are polished on one surface of the substrate which has been subjected to the treatment of the above (3) by belt sander polishing 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. Then 100 ° C for 1 hour, 120 ° C for 3 hours, 150 ° C
The resin filler 10 was cured by heat treatment for 1 hour at 180 ° C. for 7 hours.

In this way, the surface layer portion of the resin filler 10 formed in the through hole 9 and the conductor circuit non-forming portion and the surface of the lower conductor circuit 4 are flattened, and the side faces of the resin filler 10 and the lower conductor circuit 4 are flattened. 4a firmly adheres to each other through the roughened surface, and the inner wall surface 9a of the through hole 9 and the resin filler 10
An insulating substrate was obtained in which and were firmly adhered to each other via the roughened surface (see FIG. 2D). Through this step, the resin filler 10
And the surface of the lower conductor circuit 4 are flush with each other.

(5) The above substrate is washed with water and acid-degreased, then soft-etched, and then an etching solution is sprayed on both sides of the substrate to spray the surface of the lower conductor circuit 4, the land surface of the through hole 9 and the inner wall. By etching and, roughened surfaces 4a and 9a were formed on the entire surface of the lower conductor circuit 4 (see FIG. 3A). As an etching solution, an etching solution (Mec Etch Bond, manufactured by Mec Co., Ltd.) containing 10 parts by weight of an imidazole copper (II) complex, 7 parts by weight of glycolic acid and 5 parts by weight of potassium chloride was used.

(6) The above-mentioned resin composition for forming a roughened surface (viscosity: 1.5 Pa · s) of B was coated on both surfaces of the substrate by a roll coater, left standing for 20 minutes in a horizontal state, and then at 60 ° C. In 3
Drying was performed for 0 minutes to form a roughened surface forming resin layer 2a. Further, the roughened surface forming resin composition (A) (viscosity: 7 Pa · s) of A is applied onto the roughened surface forming resin layer 2a using a roll coater, and left standing in a horizontal state for 20 minutes, Drying was performed at 60 ° C. for 30 minutes to form a roughened surface forming resin layer 2b, and a roughened surface forming resin layer having a thickness of 35 μm was formed (see FIG. 3B).

(7) A photomask film on which a black circle having a diameter of 85 μm is printed is adhered to both surfaces of the substrate 1 on which the resin layer for forming a roughened surface in the above (6) is adhered, and 500 mJ / cm 2 is applied by an ultra-high pressure mercury lamp. After exposure at ² intensities, it was spray-developed with a DMDG solution. After that, the substrate was further exposed to an intensity of 3000 mJ / cm ² by an ultra-high pressure mercury lamp and exposed to 10
An interlayer resin having a thickness of 35 μm, which has been subjected to heat treatment at 0 ° C. for 1 hour, at 120 ° C. for 1 hour, and at 150 ° C. for 3 hours, and has a via hole opening 6 with a diameter of 85 μm and excellent in dimensional accuracy equivalent to a photomask film An insulating layer 2 was formed (Fig. 3
(See (c)).

(8) The substrate on which the via hole openings 6 are formed is immersed in a solution containing 800 g / l of chromic acid at 70 ° C.
The surface of the interlayer resin insulation layer 2 was roughened (depth: 3 μm) by immersing for a minute and dissolving and removing the epoxy resin particles existing on the surface of the interlayer resin insulation layer 2 (see FIG. 3D).

(9) Next, the substrate after the above treatment was immersed in a neutralizing solution (manufactured by Shipley Co.) and washed with water. Further, a palladium catalyst (manufactured by Atotech Co., Ltd.) was applied to the surface of the roughened substrate to attach catalyst nuclei to the surface of the interlayer resin insulating layer 2 and the inner wall surface of the via hole opening 6.

(10) Next, the substrate was immersed in an electroless copper plating solution having the following composition to form an electroless copper plating layer 12 having a thickness of 0.8 μm on the entire rough surface (see FIG. )reference). [Electroless plating aqueous solution] NiSO ₄ 0.003 mol / l Tartaric acid 0.200 mol / l Copper sulfate 0.030 mol / l HCHO 0.050 mol / l NaOH 0.100 mol / l α, α′-bipyridyl 40 mg / l polyethylene glycol (PEG) 0.10 g / l [electroless plating conditions] 40 minutes at a liquid temperature of 35 ° C

(11) A commercially available photosensitive dry film is attached to the electroless copper plating layer 12, a mask is placed, and 100
The plating resist 3 having a thickness of 25 μm was provided by exposing at mJ / cm ² and developing with a 0.8% sodium carbonate aqueous solution (see FIG. 4B).

(12) Then, the substrate is washed with water at 50 ° C. to degrease it, washed with water at 25 ° C., further washed with sulfuric acid, and then electrolytic copper plating is performed under the following conditions, followed by electrolytic copper plating. Layer 13 was formed. The electrolytic copper plating layer 13 was formed thicker than the plating resist 3 (see FIG. 4 (c)). [Electrolytic plating aqueous solution] Sulfuric acid 2.24 mol / l Copper sulfate 0.26 mol / l Additive 19.5 ml / l (Aparatotech Japan Co., Kaparaside GL) [Electrolytic plating conditions] Current density 1 A / dm ² hours 65 minutes temperature 22 ± 2 ℃

(13) Next, the surface layer portion of the electrolytic copper plating layer 13 was removed using an etching solution containing an organic acid salt and a cupric complex. By this treatment, electrolytic copper plating layer 1
At the same time as removing the surface layer portion of No. 3, a roughened surface was formed on the upper surface of the electrolytic copper plating layer 13 (see FIG. 4D).

(14) After stripping and removing the plating resist 3 with 5% KOH, the electroless plating layer 12 under the plating resist 3 is treated with an etching solution containing an organic acid salt and a cupric complex to dissolve and remove it. And electroless copper plating layer 12
By forming a roughened surface on the side surface and the surface of the electrolytic copper plating layer 13, a conductor circuit (including via hole 7) 5 having a thickness of 18 μm and having a roughened surface formed on the surface was formed. further,
The surface of the interlayer resin insulation layer 2 between the conductor circuits located in the conductor circuit non-formation portion is etched by 1 μm by immersing it in a solution containing 800 g / l of chromic acid at 70 ° C. for 3 minutes, and palladium remaining on the surface is etched. The catalyst was removed (Fig. 5 (a))
reference).

(15) By repeating the above steps (5) to (14), a conductor circuit in an upper layer is formed to obtain a multilayer wiring board (see FIGS. 5B to 6B). .

(16) Next, a cresol novolac type epoxy resin (manufactured by Nippon Kayaku Co., Ltd.) which was dissolved in diethylene glycol dimethyl ether (DMDG) to a concentration of 60% by weight was acrylated with 50% of epoxy groups. 46.67 parts by weight of a property imparting oligomer (molecular weight: 4000), 6.67 parts by weight of a bisphenol A type epoxy resin (manufactured by Yuka Shell Co., trade name: Epicoat 1001) of 80% by weight dissolved in methyl ethyl ketone, and also bisphenol 6.67 parts by weight of A-type epoxy resin (Yukaka Shell Co., Ltd., trade name: Epicoat E-1001-B80), imidazole curing agent (Shikoku Kasei Co., Ltd., trade name: 2E
4MZ-CN) 1.6 parts by weight, which is a photosensitive monomer 2
Functional acrylic monomer (Nippon Kayaku Co., Ltd., trade name: R60
4) 4.5 parts by weight, 1.5 parts by weight of a polyvalent acrylic monomer (manufactured by Kyoeisha Chemical Co., Ltd., trade name: DPE6A), a leveling agent consisting of an acrylic acid ester polymer (manufactured by Kyoeisha Chemical Co., Ltd., trade name: Polyflow No.) .75) 0.36 parts by weight in a container, stirred and mixed to prepare a mixed composition,
2.0 parts by weight of Irgacure I-907 (manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator and 0.2 parts by weight of DETX-S (manufactured by Nippon Kayaku) as a photosensitizer for the mixed composition. By adding 0.6 parts by weight of DMDG and 1.4 parts by weight of DMDG, the viscosity is 1.4 ± 0.3 Pa at 25 ° C.
A solder resist composition adjusted to s was obtained. The viscosity is measured by a B-type viscometer (DVL-B type manufactured by Tokyo Keiki Co., Ltd.).
When the speed is 60 min ⁻¹ (rpm), the rotor No. 4,
In the case of 6 min ^-1 (rpm), the rotor No. According to 3.

(17) Next, the solder resist composition is applied to both surfaces of the multilayer wiring board in a thickness of 20 μm,
After performing a drying treatment under conditions of 20 ° C. for 20 minutes and 70 ° C. for 30 minutes, a photomask having a thickness of 5 mm on which a pattern of a solder resist opening portion is drawn is brought into close contact with the solder resist layer, and an ultraviolet ray of 1000 mJ / cm ² is applied. Exposed with DM
It was developed with a TG solution to form an opening having a diameter of 200 μm. Then, heat treatment is further performed under the conditions of 80 ° C. for 1 hour, 100 ° C. for 1 hour, 120 ° C. for 1 hour, and 150 ° C. for 3 hours to cure the solder resist layer,
A solder resist layer 14 having openings and a thickness of 20 μm was formed.

(18) Next, the substrate on which the solder resist layer 14 was formed was nickel chloride (30 g / l), sodium hypophosphite (10 g / l), sodium citrate (10 g / l).
g / l) in pH = 5 electroless nickel plating solution 2
After immersion for 0 minute, a nickel plating layer 15 having a thickness of 5 μm was formed in the opening. In addition, the substrate is made of potassium gold cyanide (2 g / l), ammonium chloride (75 g / l),
It is immersed in an electroless plating solution containing sodium citrate (50 g / l) and sodium hypophosphite (10 g / l) for 23 seconds under the condition of 93 ° C. to have a thickness of 0.03 μm on the nickel plating layer 15. The gold plating layer 16 was formed.

(19) Then, solder paste is printed on the openings of the solder resist layer 14 and reflowed at 200 ° C. to form solder bumps (solder bodies) 17,
A multilayer wiring printed circuit board having solder bumps 17 was manufactured (see FIG. 6C).

(Example 2) A. Preparation of resin film for interlayer resin insulation layer Bisphenol A type epoxy resin (epoxy equivalent 46
9, Epicort 1001) 30 manufactured by Yuka Shell Epoxy Co., Ltd.
40 parts by weight, cresol novolac type epoxy resin (epoxy equivalent 215, Epicron N-673 manufactured by Dainippon Ink and Chemicals, Inc.), triazine structure-containing phenol novolac resin (phenolic hydroxyl equivalent 120, Dainippon Ink and Chemicals Feno Light KA-705
2) 30 parts by weight of 20 parts by weight of ethyl diglycol acetate and 20 parts by weight of solvent naphtha were dissolved by heating while stirring, and epoxidized polybutadiene rubber having a terminal end (Denalex R-45 EPT manufactured by Nagase Kasei Kogyo Co., Ltd.)
Epoxy resin composition containing 15 parts by weight, 1.5 parts by weight of 2-phenyl-4,5-bis (hydroxymethyl) imidazole pulverized product, 2 parts by weight of finely pulverized silica, and 0.5 parts by weight of silicon-based defoaming agent. Was prepared. The obtained epoxy resin composition was applied onto a PET film having a thickness of 38 μm by a roll coater so that the thickness after drying was 50 μm, and then dried at 80 to 120 ° C. for 10 minutes to obtain an interlayer resin. A resin film for an insulating layer was produced.

B. Preparation of Resin Filler 1) 100 parts by weight of bisphenol F type epoxy monomer (Made by Yuka Shell Co., molecular weight: 310, YL983U), the surface of which is coated with a silane coupling agent has an average particle diameter of 1.6 μm and maximum particles. With a diameter of 15 μm or less
iO ₂ spherical particles (manufactured by Adtech, CRS 1101-
170 parts by weight of CE) and 1.5 parts by weight of a leveling agent (Perenol S4 manufactured by San Nopco Co.) were placed in a container and mixed by stirring to have a viscosity of 45 to 4 at 23 ± 1 ° C.
A resin filler of 9 Pa · s was prepared. As a curing agent, an imidazole curing agent (2E4MZ-manufactured by Shikoku Kasei Co., Ltd.
(CN) 6.5 parts by weight was used.

C. Manufacturing method of printed wiring board (1) 0.8mm thick glass epoxy resin or BT
A copper clad laminate having 18 μm copper foil 8 laminated on both surfaces of a substrate 1 made of (bismaleimide triazine) resin was used as a starting material (see FIG. 7A). First, this copper clad laminate was drilled, electroless plated, and patterned to form lower conductor circuits 4 and through holes 9 on both sides of the substrate 1.

(2) Through hole 9 and lower conductor circuit 4
After washing the substrate on which water has been formed and drying it, NaOH (1
0 g / l), NaClO ₂ (40 g / l), Na ₃ PO
Blackening treatment using an aqueous solution containing ₄ (6 g / l) as a blackening bath (oxidizing bath), and NaOH (10 g / l), NaBH
A reduction treatment was performed using an aqueous solution containing ₄ (6 g / l) as a reduction bath, and roughened surfaces 4a and 9a were formed on the entire surface of the lower conductor circuit 4 including the through holes 9 (see FIG. 7 (b)). .

(3) After the resin filler described in B above is prepared, the conductor circuit non-formation portion and the conductor circuit in the through hole 9 and on one side of the substrate 1 are formed within 24 hours after the preparation by the following method. A layer of the resin filler 10 was formed on the outer edge portion of No. 4. That is, first, a resin filler was pushed into the through holes using a squeegee, and then dried at 100 ° C. for 20 minutes. Next, a mask having an opening corresponding to the conductor circuit non-formation portion is placed on the substrate, and a layer of the resin filler 10 is formed on the conductor circuit non-formation portion, which is the concave portion, using a squeegee. It was dried at 20 ° C. for 20 minutes (see FIG. 7C).

(4) The surface of the inner layer copper pattern 4 and the through hole 9 are polished on one surface of the substrate which has been subjected to the treatment of the above (3) by belt sander polishing 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, heat treatment was performed at 100 ° C. for 1 hour and at 150 ° C. for 1 hour to cure the resin filler 10.

In this manner, the surface layer portion of the resin filler 10 formed in the through hole 9 and the conductor circuit non-forming portion and the surface of the lower conductor circuit 4 are flattened, and the side faces of the resin filler 10 and the lower conductor circuit 4 are flattened. 4a firmly adheres to each other through the roughened surface, and the inner wall surface 9a of the through hole 9 and the resin filler 10
An insulating substrate was obtained in which and were firmly adhered to each other via the roughened surface (see FIG. 7D). That is, by this step, the surface of the resin filler 10 and the surface of the lower layer conductor circuit 4 are flush with each other.

(5) After washing the substrate with water and acid degreasing, soft etching, and then spraying an etching solution on both sides of the substrate by spraying to make the surface of the lower conductor circuit 4 and the land surface of the through hole 9 and the inner wall. By etching and, roughened surfaces 4a and 9a were formed on the entire surface of the lower conductor circuit 4 (see FIG. 8A). As an etching solution,
An etching solution (Mec Etch Bond, manufactured by Mec Co., Ltd.) consisting of 10 parts by weight of imidazole copper (II) complex, 7 parts by weight of glycolic acid and 5 parts by weight of potassium chloride was used.

(6) The interlayer resin insulation layer was formed on both surfaces of the substrate by adhering the resin film for interlayer resin insulation layer prepared in the above A using a vacuum laminator device by the following method (see FIG. 8 ( See b)). That is, a resin film for an interlayer resin insulation layer is placed on a substrate and attached under the conditions of a vacuum degree of 0.5 Torr, a pressure of 0.4 MPa, a temperature of 80 ° C., and a pressure bonding time of 60 seconds, and then at 100 ° C. for 3 minutes.
It was heat-cured for 0 minutes at 150 ° C. for 1 hour.

(7) Next, CO of wavelength 10.4 μm is formed on the interlayer resin insulation layer 2 through a mask having through holes.
₂ gas laser, beam diameter 4.0 mm, top hat mode, pulse width 8.0 μsec, mask through hole diameter 1.
A via hole opening 6 having a diameter of 60 μm was formed in the interlayer resin insulation layer 2 under the conditions of 0 mm and 2 shots (FIG. 8).
(See (c)).

(8) Epoxy resin particles present on the surface of the interlayer resin insulation layer 2 were immersed in a solution containing 40 g / l of permanganate at 60 ° C. for 15 minutes. Was dissolved and removed to roughen the surface of the interlayer resin insulation layer 2 including the inner wall of the via hole opening 6 (see FIG. 8D).

(9) Next, the substrate after the above treatment was immersed in a neutralizing solution (made by Shipley Co., Ltd.) and then washed with water. Further, by applying a palladium catalyst (manufactured by Atotech Co., Ltd.) to the surface of the substrate that has been roughened (roughening depth 3 μm), the surface of the interlayer resin insulation layer 2 and the inner wall surface of the via hole opening 6 are provided. The catalyst core was attached.

(10) Next, the substrate is dipped in an electroless copper plating solution having the following composition to have a thickness of 0.6 to 0.
A 9 μm electroless copper plating layer 12 was formed (FIG. 9A).
reference). [Electroless plating aqueous solution] NiSO ₄ 0.003 mol / l Tartaric acid 0.200 mol / l Copper sulfate 0.030 mol / l HCHO 0.050 mol / l NaOH 0.100 mol / l α, α′-bipyridyl 40 mg / l polyethylene glycol (PEG) 0.10 g / l [electroless plating conditions] 40 minutes at a liquid temperature of 35 ° C

(11) A commercially available photosensitive dry film is attached to the electroless copper plating layer 12, a mask is placed, and 100
The plating resist 3 having a thickness of 25 μm was provided by exposing at mJ / cm ² and developing with a 0.8% sodium carbonate aqueous solution (see FIG. 9B).

(12) Next, the substrate is washed with water at 50 ° C. to degrease it, washed with water at 25 ° C., and further washed with sulfuric acid, and then electrolytic copper plating is performed under the following conditions, followed by electrolytic copper plating. Layer 13 was formed. The electrolytic copper plating layer 13 was formed thicker than the plating resist 3 (see FIG. 9C). [Electrolytic plating aqueous solution] Sulfuric acid 2.24 mol / l Copper sulfate 0.26 mol / l Additive 19.5 ml / l (Aparatotech Japan Co., Kaparaside HL) [Electrolytic plating conditions] Current density 1 A / dm ² Time 65 minutes Temperature 22 ± 2 ℃

(13) Next, the surface layer portion of the electrolytic copper plating layer 13 was removed by using an etching solution containing an organic acid salt and a cupric complex. By this treatment, electrolytic copper plating layer 1
At the same time as removing the surface layer portion of No. 3, a roughened surface was formed on the upper surface of the electrolytic copper plating layer 13 (see FIG. 9D).

(14) After removing the plating resist 3 with 5% KOH, the electroless plating layer 12 under the plating resist 3 is treated with an etching solution containing an organic acid salt and a cupric complex to dissolve and remove it. And electroless copper plating layer 12
By forming a roughened surface on the side surface and the surface of the electrolytic copper plating layer 13, a conductor circuit (including via hole 7) 5 having a thickness of 18 μm and having a roughened surface formed on the surface was formed. further,
The surface of the interlayer resin insulation layer 2 between the conductor circuits located in the conductor circuit non-formation portion is etched by 1 μm by immersing it in a solution containing 800 g / l of chromic acid at 70 ° C. for 3 minutes, and palladium remaining on the surface is etched. The catalyst was removed (Fig. 10)
(See (a)).

(15) By repeating the above steps (5) to (14), a conductor circuit in an upper layer is formed to obtain a multilayer wiring board (see FIGS. 10 (a) to 11 (b)). . (16) Next, in the same manner as (16) to (19) of Example 1, a multilayer wiring printed board having solder bumps 17 was manufactured.
(See FIG. 11 (c)).

(Example 3) A. Preparation of resin filler A resin filler was prepared in the same manner as in Example 1.

B. Manufacture of printed wiring board (1) 0.8mm thick glass epoxy resin or BT
A copper clad laminate having 18 μm copper foil 8 laminated on both sides of a substrate 1 made of (bismaleimide-triazine) resin was used as a starting material (see FIG. 12A). First, this copper clad laminate is drilled, followed by forming a plating resist, and then subjecting this substrate to electroless copper plating to form through-holes 9. Further, a copper foil is patterned in a conventional manner. Then, inner layer copper patterns (lower layer conductor circuits) 4 were formed on both surfaces of the substrate by etching.

(2) The substrate on which the lower conductor circuit 4 is formed is washed with water and dried, and then an etching solution is sprayed onto both surfaces of the substrate to spray the surface of the lower conductor circuit 4 and the land surface and inner wall of the through hole 9. By etching and
Roughened surfaces 4a and 9a were formed on the entire surface of the lower layer conductor circuit 4 (see FIG. 12B). As an etching solution, 10 parts by weight of imidazole copper (II) complex, 7 parts by weight of glycolic acid,
A mixture of 5 parts by weight of potassium chloride and 78 parts by weight of ion-exchanged water was used.

(3) After preparing the resin filler described in the above A, within 24 hours after the preparation by the following method, the conductor circuit non-formation portion and the conductor circuit in the through hole 9 and on one surface of the substrate 1 A layer of the resin filler 10 was formed on the outer edge portion of No. 4. That is, first, a resin filler was pushed into the through holes using a squeegee, and then dried at 100 ° C. for 20 minutes. Next, a mask having an opening corresponding to the conductor circuit non-formation portion is placed on the substrate, and a layer of the resin filler 10 is formed on the conductor circuit non-formation portion which is the concave portion using a squeegee, It was dried at 20 ° C. for 20 minutes (see FIG. 12 (c)).

(4) The surface of the lower conductor circuit 4 and the land surface of the through hole 9 are polished on one surface of the substrate which has been subjected to the treatment of (3) above by belt sander polishing using belt polishing paper (manufactured by Sankyo Rikagaku Co., Ltd.) The resin filler 10 was abraded so as not to remain, and then buffed to remove scratches caused by the belt sander abrading. Such a series of polishing was similarly performed on the other surface of the substrate. Then, the filled resin filler 10 was cured by heating (see FIG. 12D).

In this way, the surface layer portion of the resin filler 10 filled in the through holes 9 and the like and the roughening layer 4a on the upper surface of the lower conductor circuit 4 are removed to smooth both surfaces of the substrate, and the resin filler 10 and the lower layer are removed. A wiring board was obtained in which the side surfaces of the conductor circuit 4 were firmly adhered to each other via the roughened surface 4a, and the inner wall surface of the through hole 9 and the resin filler 10 were firmly adhered to each other via the roughened surface 9a.

(5) Next, the same etching solution as that used in (2) above was sprayed onto both surfaces of the substrate that had been subjected to (4) above to spray the lower layer conductor circuit once flattened. By etching the surface of No. 4 and the land surface of the through hole 9, roughened surfaces 4a and 9a were formed on the entire surface of the lower conductor circuit 4 (see FIG. 13A).

(6) Next, on both surfaces of the substrate that has undergone the above steps,
While increasing the temperature of the thermosetting cycloolefin resin sheet having a thickness of 50 μm to a temperature of 50 to 150 ° C., a pressure of 0.5 MP
Vacuum laminating with a was performed to provide an interlayer resin insulation layer 2 made of a cycloolefin resin (see FIG. 13B). The degree of vacuum during vacuum pressure bonding was 10 mmHg.

(7) Next, the interlayer resin insulation layer 2 is irradiated with laser light through a mask having a through hole formed therein using an excimer laser having a wavelength of 248 nm to form a cycloolefin resin. Diameter 8 for interlayer resin insulation layer 2
A 0 μm via hole opening 6 was provided (FIG. 13C).
reference). After that, desmear treatment was performed using oxygen plasma.

(8) Next, SV manufactured by Nippon Vacuum Technology Co., Ltd.
-4540 was used to perform sputtering targeting Ni with a gas pressure of 0.6 Pa, a temperature of 80 ° C., and an electric power of 200.
The Ni metal layer 12a was formed on the surface of the interlayer resin insulation layer 2 under the conditions of W for 5 minutes. At this time, the thickness of the formed Ni metal layer 12a was 0.1 μm. Further, on the Ni metal layer 12a, sputtering targeting Cu was performed under the same conditions to form a Cu metal layer 12b. At this time, the thickness of the formed Cu metal layer 12b was 0.1 μm (see FIG. 13D).

(9) Commercially available photosensitive dry films were attached to both surfaces of the substrate which had been subjected to the above-mentioned treatment, a photomask film was placed thereon, and exposure was carried out at 100 mJ / cm ² .
Development was performed with 0.8% sodium carbonate to form a pattern of the plating resist 3 having a thickness of 25 μm (FIG. 14 (a)).
reference).

(10) Next, the substrate is washed with water at 50 ° C. to degrease it, washed with water at 25 ° C., and further washed with sulfuric acid, and then electrolytic copper plating is performed under the following conditions. Layer 13 was formed. The electrolytic copper plating layer 13 was formed thicker than the plating resist 3 (see FIG. 14B). [Electrolytic plating aqueous solution] Sulfuric acid 2.24 mol / l Copper sulfate 0.26 mol / l Additive 19.5 ml / l (Aparatotech Japan Co., Kaparaside GL) [Electrolytic plating conditions] Current density 1 A / dm ² hours 65 minutes temperature 22 ± 2 degrees

(11) Next, the surface layer portion of the electrolytic copper plating layer 13 was removed using an etching solution containing an organic acid salt and a cupric complex. By this treatment, electrolytic copper plating layer 1
At the same time as removing the surface layer portion of No. 3, a roughened surface was formed on the upper surface of the electrolytic copper plating layer 13 (see FIG. 14C).

(12) After stripping and removing the plating resist 3 with 5% KOH, the electroless plating layer 12 under the plating resist 3 is treated with an etching solution containing an organic acid salt and a cupric complex to dissolve and remove it. And electroless copper plating layer 12
By forming a roughened surface on the side surface and the surface of the electrolytic copper plating layer 13, a conductor circuit (including via hole 7) 5 having a thickness of 18 μm and having a roughened surface formed on the surface was formed (FIG. 14).
(See (d)).

(13) By repeating the above steps (5) to (14), a conductor circuit in an upper layer is formed to obtain a multilayer wiring board (see FIGS. 15 (a) to 16 (b)). . (14) Next,
In the same manner as (16) to (19) of Example 1, the solder bump 17
A multilayer wiring printed circuit board having
(See (c)).

Example 4 In the step (13) of Example 1, the surface layer portion of the electrolytic copper-plated layer was removed using an etching solution containing cupric chloride, and then an abrasive made of silicon was used. A multilayer printed wiring board was manufactured in the same manner as in Example 1 except that buffing was performed to completely remove the electrolytic copper plating layer remaining on the plating resist.

Regarding the multilayer printed wiring boards of Examples 1 to 4 thus manufactured, the multilayer printed wiring board was cross-cut to obtain the shape of the conductor circuit and the roughened surface formed on the surface, the conductor circuit and the interlayer. The presence or absence of peeling from the resin insulation layer and whether or not cracks were generated in the interlayer resin insulation layer were examined by observing the cross section with a microscope.

As a result, in the multilayer printed wiring boards manufactured in Examples 1 to 4, the conductor circuit had a uniform thickness and no undercut was observed. In addition, the roughened surface formed on the surface of the conductor circuit had a roughness sufficient to ensure adhesion with the interlayer resin insulation layer.

Further, in the multilayer printed wiring boards manufactured in Examples 1 to 4, peeling between the conductor circuit and the interlayer resin insulating layer was not observed, and no crack was observed in the interlayer resin insulating layer.

Further, the multilayer printed wiring boards manufactured in Examples 1 to 4 were subjected to a heat cycle test 1000 times under the conditions of 125 ° C. for 3 minutes and −55 ° C. for 3 minutes, and then the multilayer printed wiring board was printed in the same manner as above. The wiring board was cross-cut, and the presence or absence of peeling between the conductor circuit and the interlayer resin insulation layer and whether or not a crack had occurred in the interlayer resin insulation layer were examined by observing the cross section with a microscope.

As a result, in the multilayer printed wiring boards produced in Examples 1 to 4, no peeling between the conductor circuit and the interlayer resin insulation layer was observed, and no cracks were observed in the interlayer resin insulation layer.

[0155]

As described above, according to the method for manufacturing a multilayer printed wiring board of the present invention, the first etching treatment is performed before removing the plating resist, and the second etching process is performed after removing the plating resist. Since the roughening surface forming treatment is performed together with the etching treatment of, it is possible to manufacture a multilayer printed wiring board having a uniform thickness and no undercut, and a conductor circuit having a roughening surface on the surface. The multilayer printed wiring board manufactured by such a manufacturing method,
Since the conductor circuit having the above characteristics is formed, the connectivity and reliability are excellent.

[Brief description of drawings]

1 (a) to 1 (f) are views showing a manufacturing process of the present invention.
It is sectional drawing which shows typically the process of forming a conductor circuit on a resin insulating layer.

2 (a) to 2 (d) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board of the present invention.

3 (a) to 3 (d) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board of the present invention.

4 (a) to 4 (d) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

5A to 5C are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

6 (a) to 6 (c) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

7 (a) to 7 (d) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

8 (a) to 8 (d) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board of the present invention.

9A to 9D are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

10 (a) to 10 (c) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board of the present invention.

11A to 11C are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

12 (a) to (d) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board of the present invention.

13A to 13D are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board of the present invention.

14A to 14D are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

15A to 15C are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board according to the present invention.

16 (a) to 16 (c) are cross-sectional views showing a part of the manufacturing process of the multilayer printed wiring board of the present invention.

17 (a) to 17 (f) are cross-sectional views schematically showing a step of forming a conductor circuit on a resin insulating layer in the conventional manufacturing process of a multilayer printed wiring board.

[Explanation of symbols]

1 substrate 2 Interlayer resin insulation layer (roughened surface forming resin layer) 3 plating resist 4 Lower layer conductor circuit 4a Roughened surface 5 conductor circuit 6 Via hole openings 7 via holes 8 copper foil 9, 29 through hole 9a Roughened surface 10 Resin filler 12 Electroless copper plating layer 12a Ni metal layer 12b Cu metal layer 13 Electroplating layer 14 Solder resist layer 15 Nickel plating layer 16 Gold plating layer 17 Solder bump 22 Resin insulation layer 23 Plating resist 24 Thin film conductor layer 24a roughened surface 25 Electroplated layer 25a roughened surface

Continued front page    F term (reference) 5E346 AA15 AA43 CC04 CC09 CC10                       CC14 CC16 CC32 CC54 CC58                       DD02 DD03 DD12 DD17 DD25                       DD33 DD44 EE33 EE35 FF07                       FF15 GG15 GG16 GG17 GG18                       GG22 GG23 GG27 HH26

Claims (6)

[Claims] 1. A method of manufacturing a multilayer printed wiring board, comprising a conductor circuit and a resin insulating layer sequentially formed on a substrate, and these conductor circuits being connected through via holes.
A method for manufacturing a multilayer printed wiring board, comprising the following steps (1) to (4). (1) A step of forming a thin film conductor layer on the substrate and / or the resin insulating layer, (2) After forming a plating resist by using a dry film on a part of the thin film conductor layer, the plating resist A step of forming an electroplating layer thicker than the thickness of the plating resist on the non-formed portion, (3)
Etching the electroplating layer with a first etching solution, and (4) removing the plating resist and then using a second etching solution to form a thin film conductor layer under the plating resist. A step of removing and forming a roughened surface on the surface of the electroplating layer and the side surface of the thin film conductor layer. 2. The first etching solution is a solution containing at least one selected from the group consisting of cupric chloride, ferric chloride, persulfate, hydrogen peroxide / sulfuric acid, and an alkali etchant. Item 2. A method for manufacturing a multilayer printed wiring board according to Item 1. 3. The multilayer printed wiring board according to claim 1, wherein the first etching solution is a mixed solution containing a cupric complex and an organic acid salt, or a mixed solution containing hydrogen peroxide and sulfuric acid. Manufacturing method. 4. The second etching solution is a mixed solution containing a cupric complex and an organic acid salt, or a mixed solution containing hydrogen peroxide and sulfuric acid. A method for manufacturing the multilayer printed wiring board according to. 5. The first etching solution and the second etching solution are a mixed solution containing a cupric complex and an organic acid salt, or a mixed solution containing hydrogen peroxide and sulfuric acid, and The method for manufacturing a multilayer printed wiring board according to claim 1, wherein the first etching liquid and the second etching liquid are the same. 6. The multilayer print according to claim 1, wherein in the step (3), buffing is performed after the electroplating layer is etched using the first etching liquid. Wiring board manufacturing method.