JP2000277922A - Multilayer printed interconnection board and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sufficient permittivity by exposing a part of a dielectrics filler on the top surface of a dielectrics layer provided at a multilayer printed interconnection board, with a part of the exposed part contacted to an electrode layer with no intervention of a resin content. SOLUTION: Each dielectrics resin 2 is coated on a PET(polyethylene terephthalate) 1 whose surface is silicon-coated by screen printing, and after it is semi-settled under a specified condition, a coat layer on the dielectrics layer 2 is removed using a belt sander, forming a first exposed surface 10a where a dielectrics filler is exposed. A film 1 as a supporter is released from a primary laminated body like that, and a coat layer on the dielectrics layer 2 is removed to form a second exposed surface where a dielectrics filler is exposed. Then the exposed surface of the dielectrics layer 2 is so contacted as to sandwich between electrodes 6 and 7 to constitute an inner layer capacitor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a printed wiring board having one layer. In particular, it is suitable as a method for manufacturing a multilayer printed wiring board having an inner layer capacitor. Such a printed wiring board has I
It is suitable for C packages, module boards, electronic components and the like.

[0002]

2. Description of the Related Art One of the causes of data errors in integrated circuits (ICs) is the effect of electrical noise. In order to suppress the influence of electric noise, a method of removing electric noise (particularly high-frequency noise) by providing a large-capacity capacitor on a printed wiring board is known.

[0003] As a method of providing a capacitor on a printed wiring board, there is a method of attaching an external capacitor such as a chip capacitor to the printed wiring board, and a function of the capacitor on the printed wiring board itself by using a high dielectric constant material for an inner layer of the printed wiring board. There is a way to have. In consideration of the recent miniaturization of electronic products, the latter method of forming a capacitor by using a high dielectric constant material for the inner layer is desirable.

Various methods have been studied for incorporating a dielectric layer into a printed wiring board. JP-A-6-172618 discloses a method of laminating a copper foil after applying a dielectric resin to a substrate.
No. 6,009,045. JP-A-7-9609 discloses a method of preparing a prepreg in which a glass cloth is impregnated with a dielectric resin and laminating the prepreg with a copper foil. Japanese Patent Application Laid-Open No. H10-56251 discloses a method in which a dielectric resin is filled in a through hole provided in a substrate and then thermally cured. Japanese Patent Application Laid-Open No. Hei 11 (1999) discloses a method in which a dielectric resin is applied onto a film on which electrodes are previously formed, cured in the latter half of the coating, and further electrodes are formed thereon and then transferred to a substrate.
-26943.

[0005]

However, there is a problem that the dielectric constant of the inner layer capacitor obtained by the above-mentioned prior art is as low as less than 20 (6 to 16). Simply increasing the amount of the high dielectric filler added has a sufficient dielectric constant (30 or more, preferably 60 or more, more preferably 100 or more).
Was difficult to raise.

According to the present invention, a sufficient dielectric constant (30 or more, preferably 60 or more, more preferably 100 or more) is obtained when an inner layer capacitor is formed using a composite material containing at least a resin and a high dielectric filler. It is an object of the present invention to provide a printed wiring board having an inner layer capacitor using a high dielectric constant composite material capable of exhibiting the above, and a method for manufacturing the same.

[0007]

According to a first aspect of the present invention, at least a part of a dielectric filler is exposed on the outermost surface of a dielectric layer constituting a capacitor layer provided on a multilayer printed wiring board. The gist of the present invention is a multilayer printed wiring board in which at least a part of the exposed portion is in contact with the electrode layer without substantially interposing a resin component.

The details of the reason why the dielectric filler is exposed on the surface of the dielectric layer and the exposed portion contacts the electrode layer without substantially interposing the resin component to increase the dielectric constant are unknown. It is presumed that this is to reduce the interface resistance between the dielectric layer and the electrode layer.

It is preferable that a contact portion of the exposed portion of the dielectric filler with the electrode is subjected to a chemical or physical surface treatment. The term "chemical or physical surface treatment" as used herein means that the exposed portion of the dielectric filler in contact with the electrode is, for example, an etching process using a chemical solution or a plasma gas in removing the coating layer, a polishing process, a sandblasting process, or the like. It means that it has a trace of processing. The exposed portion of the dielectric filler subjected to such a surface treatment can secure a good electrical connection to the electrode layer with a physical anchor effect, and can improve the performance of the capacitor.

According to a second aspect of the present invention, there is provided a method of manufacturing a multilayer printed wiring board having at least one dielectric layer made of a dielectric resin containing a dielectric filler and a resin, wherein at least the following (a) to (a): The gist is a method for manufacturing a printed wiring board having the step g).

(A) a step of processing the dielectric resin into a sheet-like dielectric layer; This is because the thickness of the dielectric layer can be easily controlled by using a method of laminating a dielectric layer obtained by processing a dielectric resin into a sheet in advance. As the resin used in the present invention, a thermoplastic resin, a thermosetting resin, or a resin obtained by modifying these with a photopolymerizable group or an elastomer can be used. Known resins such as an extrusion molding method, a doctor blade method, and a screen printing method can be used for forming these resins into sheets.

As the thermoplastic resin, polystyrene (P
S) resin, polyethylene (PE) resin, polyetherimide (PEI) resin, polysulfone (PSF) resin,
Polyetherketone (PEK) resin, polyurethane (P
U) resin, polyolefin resin, polypropylene (P
P) resin, polycarbonate (PC) resin, polyacetal (POM) resin, fluorine (PTFE) resin, and modified resins thereof can be used. As the thermosetting resin, an epoxy resin is preferable. BP type (especially BPA type, BPF type), cresol type, novolak type,
Cresol novolak type epoxy resin is preferred.

The dielectric filler used in the present invention includes:
BaTiO_ThreeSystem, SrTiO_ThreeSystem, SrSnO_ThreeSystem, Zr
TiO_FourSystem, (ZrSn) TiO_FourSystem, CaTiO_Threesystem,
PbTi_1/2Zr_1/2O_ThreeSystem, Pb (Mg_2/3Nb_1/3) O_Three
System, Ba (Mg_1/3Nb_2/3) O _ThreeSystem, Sr (Mg_1/3Nb
_2/3) O_ThreeSystem, Ba (Mn_1/3Nb_2/3) O_ThreeSystem, Sr (Z
n_1/3Nb_2/3) O_ThreeSystem, Ba (Zn_1/3Nb_2/3) O_Threesystem,
Nd_TwoTi_TwoO₇A system or the like can be used. These are simply
They can be used alone or in combination of two or more. Ma
The SiO_Two, ZrO_Two, TiO_Two, AlN, SiC, gas
You may mix and use with a lath etc.

(B) A step of bonding the support and the dielectric layer is provided. By bonding the sheeted dielectric layer to the support, the handling of the dielectric layer becomes easy and the contamination of the dielectric layer is prevented. The “support” here is a film or a plate,
In addition, it has a property that can be easily peeled or removed from the dielectric layer. It is desirable to use a dimensionally stable material that does not shrink when heated to about 100 ° C.

For example, polyethylene terephthalate (P
ET) resin, polyimide (PI) resin, polyether sulfone (PES) resin, polyphenylene sulfide (PPS) resin, polyetherimide (PEI) resin,
Use a resin film or resin plate made of a polyetheretherketone (PEEK) resin, an aromatic polyester (LCP) resin, a zindiotactic polystyrene (SPS) resin, a fluorine-polyethersulfone (PTFE-PPS) alloy resin, or the like. be able to. Also copper,
A single or alloy metal film or metal plate of aluminum, brass, nickel, iron or the like can be used. These are, for example, two, such as a combination of copper and aluminum.
It may have a multilayer structure of more than layers. The surface of the film or plate may be subjected to a surface treatment such as a silicone resin coating so as to be easily separated from the dielectric resin layer.

(C) removing the coating layer which does not contain the dielectric filler formed near the surface of the dielectric layer or whose content of the dielectric filler is smaller than the content at the center in the thickness direction; And a first exposed surface forming step of exposing at least a part of the dielectric filler.
The present inventors have found that when a dielectric resin containing a dielectric filler is formed into a sheet, the dielectric filler is not included in the vicinity of the outermost surface of the dielectric layer, or the content of the dielectric filler is in the center in the thickness direction. It was found that a coating layer (2a in FIG. 2) having a smaller content than the content in the part was formed. By forming the exposed surface (9b in FIG. 3) exposing the dielectric filler by removing the film layer in advance and forming the conductor layer, the dielectric constant of the dielectric layer can be dramatically increased. it can.

As a method for removing the coating layer, a method using polishing using a sander or the like, a method using sand blasting or the like,
A method using a chemical such as potassium permanganate or chromic acid, plasma etching, RIE (reactive ion etching), or the like can be used.

To prevent the resin layer from absorbing moisture, a belt sander, sand blast, plasma etching, RI
It is preferable to use a so-called dry removal method such as E (reactive ion etching). By using the dry removal method, a printed wiring board having excellent reliability such as migration resistance can be obtained. In order to reduce costs, it is preferable to use a so-called wet removal method using a chemical such as potassium permanganate or chromic acid. Since the wet removal method is excellent in automation of a production line and excellent in mass productivity, the production cost of a printed wiring board can be effectively reduced.

(D) A laminating step of arranging the first exposed surface of the dielectric layer so as to face the circuit forming surface of the printed wiring board on which the circuit is formed, and pressurizing and heating to integrate. The “first exposed surface” where the dielectric filler is exposed is arranged to face the circuit forming surface of the printed wiring board, and is integrated by pressing and heating using a press machine or the like to form a laminate having a dielectric layer. The body can form. Press pressure is 30-1000kgf /
cm ² is preferred. If the pressing pressure is 30 kgf / cm ² or less, the adhesion of the dielectric layer is not sufficient, and the pressure is 1000 kgf / c.
and m ² or more is because poor productivity.

(E) a step of removing the support. Basically, a method of peeling and removing the support is used. For peeling, a method such as winding up a support made of a film or a plate from a substrate end using a mechanical device can be applied. Further, by selecting the material of the support, it is possible to remove the support using the above-mentioned dry or wet removal method as the method of removing the coating layer.

(F) removing the coating layer which does not contain the dielectric filler formed near the surface of the dielectric layer or whose content of the dielectric filler is smaller than the content at the center in the thickness direction; And a second exposed surface forming step of exposing at least a part of the dielectric filler.
Similarly to the first exposed surface forming step, the dielectric constant of the dielectric layer can be dramatically increased by forming the conductor layer after removing the coating layer in advance to expose the dielectric filler.
As the method for removing the coating layer, the support can be removed using the above-mentioned dry or wet removal method.

(G) forming a metal layer on the second exposed surface of the dielectric layer; A circuit can be formed on the second exposed surface by using a known metal layer forming method such as an electroless plating method, an electrolytic plating method, or a combination thereof. The circuit may be formed on a second exposed surface after forming a so-called laser via using a laser processing machine. As the laser beam machine, known laser machines such as an infrared laser, an ultraviolet laser, and an excimer laser can be used.

According to a third aspect of the present invention, there is provided a method for manufacturing a multilayer printed wiring board having at least one dielectric layer made of a dielectric resin containing a dielectric filler and a thermosetting resin. The gist of the present invention is a method for manufacturing a printed wiring board including the steps of) to (g).

(A) a step of applying the dielectric resin on a support; The term “support” as used herein refers to a film-like or plate-like material having a property that can be easily peeled or removed from the B-staged dielectric resin layer. It is desirable to use a dimensionally stable material that does not shrink when heated to about 100 ° C.

For example, polyethylene terephthalate (P
ET) resin, polyimide (PI) resin, polyether sulfone (PES) resin, polyphenylene sulfide (PPS) resin, polyetherimide (PEI) resin,
Use a resin film or resin plate made of a polyetheretherketone (PEEK) resin, an aromatic polyester (LCP) resin, a zindiotactic polystyrene (SPS) resin, a fluorine-polyethersulfone (PTFE-PPS) alloy resin, or the like. be able to. Also copper,
A single or alloy metal film or metal plate of aluminum, brass, nickel, iron or the like can be used. These are, for example, two, such as a combination of copper and aluminum.
It may have a multilayer structure of more than layers. The surface of the film or plate may be subjected to a surface treatment such as a silicone resin coating so as to be easily separated from the dielectric resin layer.

A dielectric resin is applied on the support. As a coating method, a known technique can be applied as long as a resin layer having a uniform thickness can be formed. For example, a dokuda blade method, a screen printing method, various printing methods using a roll coater or a curtain coater used for producing a ceramic green sheet, and the like can be used.

The resin component constituting the “dielectric resin” in the present invention is basically a thermosetting resin, but is a modified thermosetting resin into which a photocurable substituent or a thermoplastic elastomer is introduced. This is a concept that also includes As the thermosetting resin, epoxy resin, unsaturated polyester resin, urea resin, melamine resin, phenol resin, amino resin, polyurethane resin, silicone resin, addition polymerization type polyimide resin, bismaleimide type polyimide resin and the like can be used. it can. Among these, epoxy resin, addition polymerization type polyimide resin and bismaleimide type polyimide resin are used because heat resistance, insulation, moisture resistance and mechanical strength are high, the coefficient of thermal expansion is small, and the shrinkage due to curing is small. Is preferred.

Among these, it is more preferable to contain an epoxy resin. Examples of the “epoxy resin” include bisphenol A type epoxy resin, bromide bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, A fluorene type epoxy resin, a phenol novolak type epoxy resin, an orthocresol type epoxy resin, a trishydroxyphenylmethane type epoxy resin, a tetraphenolethane type epoxy resin and the like can be used. Each of the cured products made of these is excellent in heat resistance and the like. The above thermosetting resin may be modified.

In particular, it is preferable to use bisphenol A type epoxy resin (product name: E-828), bisphenol F type epoxy resin (product name: E-807), phenol novolak type epoxy resin, etc. (product name: E-152). Among these resins, it is preferable to use a bisphenol A type epoxy resin (product name: YL-980) and a bisphenol F type epoxy resin (product name: YL-983U) which are particularly low-chlorinated epoxy resins. By using this low-chlorinated epoxy resin, short-circuiting of the dielectric layer can be prevented even when the printed wiring board is used in a high-temperature and high-humidity environment. These epoxy resins may be used alone or in combination of two or more. Further, a photo-curable substituent, a thermoplastic elastomer, or the like may be introduced, or may be modified with another compound. All of the product names shown above are the product names of Union Carbide.

Since these epoxy resins greatly differ in the properties of the cured product obtained depending on the type of curing agent, in particular, a cured product capable of forming a cured product having high heat resistance, low hygroscopicity, and high insulation properties. It is preferred to use agents. As such a "curing agent", polyamine, acid anhydride, polyphenol, isocyanate, organic acid, amines, imidazole, Lewis acid and the like can be used. Among these, it is preferable to use an imidazole-based curing agent. Further, among the imidazole-based curing agents, it is preferable to use an imidazole-based curing agent that is solid at normal temperature (20 to 25 ° C.).

Examples of the imidazole-based curing agent which is solid at normal temperature include imidazole (product name: Z),
2-methylimidazole (product name: 2MZ), 2-ethylimidazole (product name: 2EZ), 2-isopropylimidazole (product name: 2IZ), 2-n-propylimidazole (product name: PrZ), 2-n-butylimidazole (product name) BuZ), 2-phenylimidazole (product name;
2PZ), 2-undecylimidazole (product name; C11)
Z), 2-heptadecyl imidazole (product name; C17
Z), 2- (2'-methylimidazolyl-4 ')-benzimidazole (product name: 2MZ-BZ), 2- (2'-
Phenylimidazolyl-4 ′)-benzimidazole (product name: 2PZ-BZ), 4-methylimidazole (product name: 4MZ), 2,4-dimethylimidazole (product name;
2,4-DMZ), 2-phenyl-4-methylimidazole (product name; 2P4MZ), 2-cyanoimidazole (product name: 2CNZ), 4-cyanoimidazole (product name;
4CNZ), 4-methyl-5-cyanomethylimidazole (product name: 4M5CNZ), 2-methyl-4-cyanomethylimidazole (product name: 2M4CNZ), 1-cyanoethyl-2-phenylimidazole (2PZ-CN),
1-cyanoethyl-2-undecylimidazole (C1
1Z-CN), 2-phenyl-4-cyanomethylimidazole (product name; 2P4CNZ), 4-cyanomethyl-imidazole (product name: 4CNMZ), 4-azabenzimidazole (product name; ZP), 2-hydroxy-4-azabenz Imidazole (product name: OHZP), 2-hydroxymethyl-4-azabenzimidazole (product name: HZ)
P), 2-mercapto-4-azabenzimidazole (product name: SHZP), 2-phenyl-4,5-dihydroxymethylimidazole (product name: 2PHZ), 2-phenyl-4-methyl-5-hydroxymethylimidazole (product name) 2P4MHZ).

As the dielectric filler used in the present invention,
BaTiO_ThreeSystem, SrTiO_ThreeSystem, SrSnO_ThreeSystem, Zr
TiO_FourSystem, (ZrSn) TiO_FourSystem, CaTiO_Threesystem,
PbTi_1/2Zr_1/2O_ThreeSystem, Pb (Mg_2/3Nb_1/3) O_Three
System, Ba (Mg_1/3Nb_2/3) O _ThreeSystem, Sr (Mg_1/3Nb
_2/3) O_ThreeSystem, Ba (Mn_1/3Nb_2/3) O_ThreeSystem, Sr (Z
n_1/3Nb_2/3) O_ThreeSystem, Ba (Zn_1/3Nb_2/3) O_Threesystem,
Nd_TwoTi_TwoO₇A system or the like can be used. These are simply
They can be used alone or in combination of two or more. Ma
The SiO_Two, ZrO_Two, TiO_Two, AlN, SiC, gas
You may mix and use with a lath etc.

The amount of the dielectric filler added to the dielectric resin is preferably from 10 to 90% by volume. If the content is less than 10% by volume, the dielectric constant does not increase, and if the content is more than 90% by volume, the moldability deteriorates. More preferably, the content is 20 to 80% by volume. The average particle size of the dielectric filler is preferably 0.1 to 50 μm. If the thickness is 0.1 μm or less, the dielectric constant does not increase due to insufficient contact between the dielectric fillers. If the thickness is 50 μm or more, the addition amount cannot be increased much, and the moldability deteriorates. More preferably, it is 1 to 30 μm.

Further, a conductive filler may be added to the dielectric resin. The added amount of the conductive filler is 0.5 to 50
% By volume is preferred. If the content is 0.5% by volume or less, it does not contribute to the contact between the dielectric fillers, and if the content is 50% by volume or more, the insulating property of the dielectric resin layer is lost. More preferably, it is 1 to 30% by volume. The average particle size of the conductive filler is preferably 0.01 to 50 μm. If the thickness is 0.01 μm, it is difficult to disperse the conductive filler, and if it is 50 μm or more, the moldability deteriorates. More preferably 0.1 to 10
μm.

(B) A step of semi-curing the dielectric resin together with the support to form a B stage. The term "B-stage shape" as used herein refers to a state in which the resin has slightly hardened and gelation has progressed. For example, when expressed as a percentage of the total curing calorific value measured by DSC (differential scanning calorimetry), this is a state in which 20 to 60% of the total curing calorific value has been generated. If the resin component consists only of thermosetting resin, DS
This step may be controlled by C. When the resin component is modified with a photocurable substituent, the resin component may be made into a semi-cured state by photopolymerization to form a so-called “B-stage shape”. In this case, this step may be controlled by the amount of light irradiation.

(C) a coating layer which does not contain the dielectric filler formed near the surface of the B-staged dielectric layer or whose content of the dielectric filler is smaller than the content at the center in the thickness direction. And a first exposed surface forming step of exposing at least a part of the dielectric filler. The present inventors have found that when a dielectric resin containing a dielectric filler is cured, no dielectric filler is contained near the outermost surface of the dielectric layer (9a in FIG. 2), or the dielectric filler is not contained. It has been found that a coating layer (2a in FIG. 2) whose amount is smaller than the content at the center in the thickness direction is formed. By forming the exposed surface (9b in FIG. 3) exposing the dielectric filler by removing the film layer in advance and forming the conductor layer, the dielectric constant of the dielectric layer can be dramatically increased. it can.

As a method for removing the coating layer, a method using polishing using a bell sander or the like, a method using sand blasting or the like,
A method using a chemical such as potassium permanganate or chromic acid, plasma etching, RIE (reactive ion etching), or the like can be used.

To prevent the resin layer from absorbing moisture, a belt sander, sandblast, plasma etching, RI
It is preferable to use a so-called dry removal method such as E (reactive ion etching). By using the dry removal method, a printed wiring board having excellent reliability such as migration resistance can be obtained. In order to reduce costs, it is preferable to use a so-called wet removal method using a chemical such as potassium permanganate or chromic acid. Since the wet removal method is excellent in automation of a production line and excellent in mass productivity, the production cost of a printed wiring board can be effectively reduced.

(D) A laminating step of arranging the first exposed surface of the dielectric layer so as to face the circuit forming surface of the printed wiring board on which the circuit is formed, and pressurizing and heating to integrate. The “first exposed surface” where the dielectric filler is exposed is arranged to face the circuit forming surface of the printed wiring board, and is integrated by pressing and heating using a press machine or the like to form a laminate having a dielectric layer. The body can form. Press pressure is 30-1000kgf /
cm ² is preferred. If the pressing pressure is 30 kgf / cm ² or less, the adhesion of the dielectric layer is not sufficient, and the pressure is 1000 kgf / c.
and m ² or more is because poor productivity.

(E) A step of removing the support is provided. Basically, a method of peeling and removing the support is used. For peeling, a method such as winding up a support made of a film or a plate from a substrate end using a mechanical device can be applied. Further, by selecting the material of the support, it is possible to remove the support using the above-mentioned dry or wet removal method as the method of removing the coating layer.

(F) A film layer containing no dielectric filler formed near the surface of the dielectric layer or having a content of the dielectric filler smaller than that at the center in the thickness direction is removed. And a second exposed surface forming step of exposing at least a part of the dielectric filler.
Similarly to the first exposed surface forming step, the dielectric constant of the dielectric layer can be dramatically increased by forming the conductor layer after removing the coating layer in advance to expose the dielectric filler.
As the method for removing the coating layer, the support can be removed using the above-mentioned dry or wet removal method.

(G) forming a metal layer on the second exposed surface of the dielectric layer; A circuit can be formed on the second exposed surface by using a known metal layer forming method such as an electroless plating method, an electrolytic plating method, or a combination thereof. The circuit may be formed on a second exposed surface after forming a so-called laser via using a laser processing machine. As the laser beam machine, known laser machines such as an infrared laser, an ultraviolet laser, and an excimer laser can be used.

According to a fourth aspect of the present invention, there is provided a method for producing a multilayer printed wiring board having at least one dielectric layer made of a dielectric resin containing a dielectric filler and a thermosetting resin, wherein at least (a) The gist is a method for manufacturing a printed wiring board having the steps (d), (h), and (g). still,
The steps (a) to (d) and (g) are the same as in the third aspect of the present invention, and will not be described below.

(H) continuously removing the support and the coating layer formed near the surface of the dielectric layer under the support,
Second exposing at least a part of the dielectric filler
Having an exposed surface forming step. The present invention is characterized in that the steps (e) and (f), which were performed independently in the invention of claim 1, are continuously performed as the following step (h). As a method for removing the support and the film layer, a method using polishing or sandblasting using a bell sander or the like, a chemical solution such as potassium permanganate or chromic acid, plasma etching, RIE (reactive ion etching), or the like is used. Can be used. If the material of the support to be used is selected in accordance with the above-described various removal methods, it is possible to efficiently and continuously remove the support and the coating layer.

To prevent the resin layer from absorbing moisture, a belt sander, sand blast, plasma etching, RI
It is preferable to use a so-called dry removal method such as E (reactive ion etching). By using the dry removal method, a printed wiring board having excellent reliability such as migration resistance can be obtained. In order to reduce costs, it is preferable to use a so-called wet removal method using a chemical such as potassium permanganate or chromic acid. Since the wet removal method is excellent in automation of a production line and excellent in mass productivity, the production cost of a printed wiring board can be effectively reduced.

[0046]

EXAMPLES Examples of the present invention will be shown below, but the printed wiring board of the present invention is not limited to the specific structures shown in the following examples.

Example 1 Example 1 shows an example using an evaluation sample. (1) Preparation of dielectric resin Dielectric filler, thermosetting resin and conductive filler are shown in Table 1.
And then kneading with a three-roll mill to produce a high dielectric constant composite material. The details of the resin and filler used are shown below. Details of the resins A and B in Table 1 are as follows. Resin A: 95 parts by weight of epoxy resin (E-807 manufactured by Yuka Shell) Imidazole-based curing agent (Shikoku Chemicals 2E4MZ-CN)
5 parts by weight Resin B; Epoxy resin (Epicoat 828 manufactured by Yuka Shell) 95
Parts by weight imidazole-based curing agent (Shikoku Chemicals 2E4MZ-CN)
5 parts by weight

As the dielectric filler, BaTiO ₃ (manufactured by Kyoritsu Ceramics Co., Ltd., average particle size: 23 μm) is used. The details of the conductive fillers C and D are shown below. Conductive filler C; copper powder (made by Fukuda Metal, average particle size 8μ)
m) Conductive filler D; carbon black (Tokai Carbon, average particle size 0.038 μm)

(2) Preparation of Sample for Measuring Dielectric Constant Each dielectric resin shown in Table 1 is applied on a PET film having a surface coated with silicon by using a screen printing method.
Next, semi-curing is performed at 80 ° C. × 1.5 hours. Thereafter, the coating layer on the dielectric layer is removed using a belt sander to form a first exposed surface where the dielectric filler is exposed.
In another sample, the film layer is removed by sandblasting, plasma etching, or a potassium permanganate solution to form a first exposed surface where the dielectric filler is exposed.

Next, a copper substrate having a thickness of 0.8 mm is placed on the first exposed surface, and laminated at a pressure of 30 kg / cm ^{2 in} vacuum to obtain a primary laminated body. The PET film is peeled off from the primary laminate. Next, the coating layer on the dielectric layer is removed using a belt sander to form a second exposed surface where the dielectric filler is exposed. In another sample in which the first exposed surface is formed using sandblasting, the coating layer is removed using sandblasting, plasma etching, and a potassium permanganate solution to form a second exposed surface where the dielectric filler is exposed. . A copper substrate having a thickness of 0.8 mm is placed on the second exposed surface, and is laminated under a pressure of 30 kg / cm ² in a vacuum to form a copper substrate.
The sample is heated at a temperature of 5 ° C. × 5 hours to obtain a sample for dielectric constant measurement. In addition, as a comparative example, a sample in which only the removal of the film layer is omitted is separately manufactured under the same conditions.

(3) Measurement of dielectric constant of dielectric constant measurement sample 1 MHz of dielectric constant measurement sample prepared in (2) above
The dielectric constant in the JIS was measured using an impedance analyzer (HP4194A, manufactured by Hewlett-Packard).
It is measured according to K 6911. Table 1 shows the results.

[0052]

[Table 1]

From the results in the table, it can be seen that the dielectric constants of the examples manufactured by using the manufacturing method of the present invention are as good as 60 or more. On the other hand, it can be seen that the dielectric constant of each of the comparative examples manufactured by the conventional method without removing the coating layer is less than 60.

(Embodiment 2) Embodiment 2 is a method for manufacturing a printed wiring board in which a dielectric layer is built in a so-called core substrate. First, as shown in FIG. 1, each dielectric resin 2 shown in Table 1 is applied on a PET film 1 whose surface is coated with silicon by using a screen printing method. Next, 80 ° C x
Semi-cured for 1.5 hours. Thereafter, the coating layer on the dielectric layer 2 is removed using a belt sander to form a first exposed surface where the dielectric filler is exposed (not shown).

Next, as shown in FIG. 4, an electrode 7 is provided on an insulating substrate 4 made of a copper-clad BT (bismaleimide-triazine) -glass cloth composite material by a subtractive method. This is referred to as an insulating substrate A. Next, as shown in FIG. 5, the electrode forming surface of the insulating substrate A and the first exposed surface of the dielectric layer are arranged to face each other,
The primary laminated body B is obtained by laminating under a pressure of g / cm ² (FIG. 6).

As shown in FIG. 7, the support 1 is separated from the primary laminate B. Next, the coating layer on the dielectric layer 2 is removed using a belt sander to form a second exposed surface where the dielectric filler is exposed (not shown).

Next, as shown in FIG. 8, an electrode of an insulating substrate C in which an electrode 6 is provided by a subtractive method on an insulating substrate 3 made of a copper-clad BT (bismaleimide-triazine) -glass cloth composite material. The forming surface and the second exposed surface of the primary laminate are arranged to face each other. 30k in vacuum
The layers are laminated at a pressure of g / cm ² and heated under the condition of 150 ° C. × 5 hours to obtain a secondary laminate D (FIG. 9). The portion of the dielectric layer 2 sandwiched between the electrodes 6 and 7 constitutes an inner layer capacitor.

As shown in FIG. 10, through holes 8 having a diameter of 300 μm are formed in the secondary laminate D using a YAG laser. Next, after the secondary laminate D is immersed in the catalytically active liquid, the entire surface is subjected to electroless copper plating. Subsequently, electrolytic copper plating is performed to establish electrical continuity between the front and back surfaces of the secondary laminate D. 2
Next, a plating resist layer is formed on the front and back surfaces of the laminate D, and the wiring pattern is exposed and developed by photolithography.
After etching and removing the copper plating layer in unnecessary portions as a circuit, the plating resist layer is peeled off to obtain a core substrate E having the dielectric layer 2 built therein (FIG. 11).

(Embodiment 3) Embodiment 3 shows a method of manufacturing a printed wiring board in which a dielectric layer is incorporated as a so-called build-up layer. First, the insulating substrate 11 on which a circuit is formed as shown in FIG. The insulating substrate 11 is made of a BT (bismaleimide-triazine) -glass cloth composite material. A through-hole conductor 12 is formed in the through-hole by copper plating. Further, the through-hole is filled and hardened with a filling material 13 obtained by adding a silica filler to an epoxy resin. An electrode 14 is provided on the surface of the insulating substrate 11.
Are formed.

As shown in FIG. 13, the surface of the insulating substrate 11 on which the electrodes 14 are formed and the first exposed surface of the dielectric layer 2 formed on the support 1 are arranged so as to face each other. Then, the layers are laminated in a vacuum at a pressure of 30 kg / cm ² and heated at 150
Heating is performed under conditions of × 5 hours to obtain a laminate (FIG. 14).

As shown in FIG. 15, the support 1
Is peeled off. Next, the coating layer on the dielectric layer 2 is removed using a belt sander to form a second exposed surface where the dielectric filler is exposed (not shown).

As shown in FIG. 16, a via hole 15 having a diameter of 200 μm is formed on the second exposed surface by using a YAG laser. Next, after the laminate is immersed in a catalytically active solution, electroless copper plating is performed on the entire surface. Next, a plating resist layer is formed on the dielectric layer on which the electroless copper plating has been performed, and the wiring pattern is exposed and developed by photolithography. A circuit is formed by applying electrolytic copper plating to the wiring opening formed in the plating resist. After peeling off the plating resist layer, an unnecessary portion of the electroless copper plating layer as a circuit is removed by etching to obtain a build-up substrate having the dielectric layer 2 built therein (FIG. 17). An insulating protective layer 18 is formed on the outermost surface to protect the dielectric layer 2 (FIG. 18).

[0063]

According to the present invention, when an inner layer capacitor is formed using a composite material containing at least a resin and a high dielectric constant filler, a sufficient dielectric constant (30 or more,
It is possible to provide a printed wiring board having an inner layer capacitor using a high dielectric constant composite material capable of expressing 60 or more, more preferably 100 or more) and a method of manufacturing the same.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one example of a method for manufacturing a printed wiring board of the present invention.

FIG. 2 is an explanatory view showing an example of a conventional method for manufacturing a printed wiring board.

FIG. 3 is an explanatory view showing one example of a method for manufacturing a printed wiring board of the present invention.

FIG. 4 is an explanatory view showing an example of the method for manufacturing a printed wiring board according to claim 3;

FIG. 5 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 3;

FIG. 6 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 3;

FIG. 7 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 3;

FIG. 8 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 3;

FIG. 9 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 3;

FIG. 10 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 3;

FIG. 11 is an explanatory view showing an example of the method of manufacturing the printed wiring board according to claim 3;

FIG. 12 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 4;

FIG. 13 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 4;

FIG. 14 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 4;

FIG. 15 is an explanatory view showing an example of the method of manufacturing the printed wiring board according to claim 4;

FIG. 16 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 4;

FIG. 17 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 4;

FIG. 18 is an explanatory view showing an example of the method for manufacturing the printed wiring board according to claim 4;

[Explanation of symbols]

 Reference Signs List 1 support 2 dielectric layer 2a coating layer 3 insulating substrate 4 insulating substrate 5 copper plating layer 6 electrode 7 electrode 8 through hole 9 near surface of dielectric layer 9a cross-sectional view near surface of dielectric layer (before film layer is removed) 9b Cross-sectional view near surface of dielectric layer (after removal of coating layer) 10 Dielectric filler 10a Exposed portion of dielectric filler

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masahiko Okuyama 14-18 Takatsuji-cho, Mizuho-ku, Nagoya-shi, Aichi F-term in Japan Special Ceramics Co., Ltd. 5E346 AA13 AA42 CC08 CC21 CC32 DD03 DD07 DD23 DD24 DD44 FF07 FF13 FF14 GG09 GG15 GG17 GG18 GG22 GG28 HH01 HH31

Claims (4)

[Claims] 1. A multilayer printed wiring board having a capacitor layer composed of a dielectric layer containing at least a dielectric filler and a resin and electrode layers facing each other with the dielectric layer interposed therebetween. A multilayer printed wiring board, wherein at least a part of the dielectric filler is exposed on the surface, and at least a part of the exposed part is in contact with the electrode layer without substantially interposing a resin component. . 2. A method of manufacturing a multilayer printed wiring board having at least one dielectric layer made of a dielectric resin containing at least a dielectric filler and a resin, comprising at least the following steps (a) to (g): The method for manufacturing a printed wiring board according to claim 1, comprising: (A) a step of processing the dielectric resin into a sheet-like dielectric layer; (B) a step of bonding the support and the dielectric layer. (C) removing the coating layer which does not contain the dielectric filler formed near the surface of the dielectric layer or whose content of the dielectric filler is smaller than the content at the center in the thickness direction of the dielectric layer; A first exposed surface forming step of exposing at least a part of the body filler. (D) a laminating step in which the first exposed surface of the dielectric layer is disposed so as to face the circuit-formed surface of the printed wiring board on which the circuit is formed, and is integrated by pressurizing and heating. (E) removing the support. (F) removing the coating layer containing no dielectric filler formed in the vicinity of the surface of the dielectric layer or having a content of the dielectric filler smaller than the content at the center in the thickness direction of the dielectric layer; A second exposed surface forming step of exposing at least a part of the body filler. (G) forming a metal layer on the second exposed surface of the dielectric layer; 3. A method for manufacturing a multilayer printed wiring board having at least one dielectric layer made of a dielectric resin containing at least a dielectric filler and a thermosetting resin, wherein at least the following (a) to (g) are provided. 2. The method for manufacturing a printed wiring board according to claim 1, further comprising: (A) a step of applying the dielectric resin on a support; (B) semi-curing the dielectric resin together with the support,
The process of forming a stage. (C) removing the coating layer which does not contain the dielectric filler formed near the surface of the B-staged dielectric layer or whose content of the dielectric filler is smaller than the content at the center in the thickness direction; Forming a first exposed surface for exposing at least a part of the dielectric filler. (D) a laminating step in which the first exposed surface of the dielectric layer is disposed so as to face the circuit-formed surface of the printed wiring board on which the circuit is formed, and is integrated by pressurizing and heating. (E) removing the support. (F) removing the coating layer containing no dielectric filler formed in the vicinity of the surface of the dielectric layer or having a content of the dielectric filler smaller than the content at the center in the thickness direction of the dielectric layer; A second exposed surface forming step of exposing at least a part of the body filler. (G) forming a metal layer on the second exposed surface of the dielectric layer; 4. A method for producing a multilayer printed wiring board having at least one dielectric layer made of a dielectric resin containing a dielectric filler and a thermosetting resin, comprising at least the following (a) to (g): 2. The method for manufacturing a printed wiring board according to claim 1, further comprising: (A) a step of applying the dielectric resin on a support; (B) semi-curing the dielectric resin together with the support,
The process of forming a stage. (C) removing the coating layer which does not contain the dielectric filler formed near the surface of the B-staged dielectric layer or whose content of the dielectric filler is smaller than the content at the center in the thickness direction; Forming a first exposed surface for exposing at least a part of the dielectric filler. (D) a laminating step in which the first exposed surface of the dielectric layer is disposed so as to face the circuit-formed surface of the printed wiring board on which the circuit is formed, and is integrated by pressurizing and heating. (H) a second exposed surface forming step of continuously removing the support and the coating layer formed near the surface of the dielectric layer under the support to expose at least a part of the dielectric filler. (G) forming a metal layer on the second exposed surface of the dielectric layer;