JP2002124774A - Multilayer printed wiring board and method of manufacturing the same - Google Patents

Abstract

(57) [Problem] To solve the problem of the present invention, after the outer shape processing of a multilayer printed wiring board, the solder resist peeling on the outer shape processing cutting line and the vicinity thereof and cracks of the insulating base material in the vicinity thereof are eliminated. It is assumed that. SOLUTION: An end of forming an inner layer conductor pattern (12a, 12c) of a multilayer printed wiring board is connected to an outer layer conductor pattern (13).
Provided are a multilayer printed wiring board formed so as to be located between the forming end of a, 13c and the contour processing line 22, and a method of manufacturing the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer printed wiring board used for electronic equipment and the like.

[0002]

2. Description of the Related Art In recent years, multilayer printed wiring boards used in electronic equipment and the like have been required to have high density and high reliability.

[0003] A conventional multilayer printed wiring board will be described below.

FIG. 5 is a sectional view showing the structure of a conventional multilayer printed wiring board.

In FIG. 5, 1 is an inner layer base material, 2a, 2c
Is an inner layer circuit pattern, 3 is an outer layer base material, 4a and 4c are outer layer circuit patterns, 5 is a solder resist, 6 is a boundary line to be cut and processed to form a desired outer shape in a later step,
That is, it is a forming end of the outer shape processing, and the outer layer circuit pattern 4a,
Formed ends 2b, 2d of the inner layer circuit patterns 2a, 2c are formed below the formed ends 4b, 4d of the 4c.

Conventionally, when forming an earth pattern having a large circuit width in the vicinity of the outer shape forming end, the inner layer circuit pattern is exposed from the outer shape forming wall surface in order to design the circuit as wide as possible or due to a positional shift at the time of laminating the inner layer. In order to reduce the possibility of doing this, the above-mentioned positional relationship is often used.

[0007] Further, since the relationship between the above-mentioned positional relationship and the outer shape processing and the problem have not been grasped, the forming end of the outer shape processing and
At present, it is left to the discretion of a circuit design engineer without mentioning the positional relationship between the formation ends of the inner and outer circuit patterns.

The background on which the inventor of the present invention has grasped the problems in the outer shape processing of the conventional multilayer printed wiring board will be described below.

First, FIG. 6A shows a configuration at the time of outer shape processing, wherein 7 is an outer die of an upper die, 8 is a stripper plate of an upper die, 9 is a die of a lower die, and 10 is a lower die. It is an external shape stripper plate of a mold.

Next, the outer shape processing of the multilayer printed wiring board will be described.

FIG. 6 (b) shows the moment when the upper mold descends to the multilayer printed wiring board 0 installed on the lower mold to perform the outer shape processing.

The multi-layer printed wiring board 0 is cut into the outer shape processing cutting line 6.
When cutting on the upper side, the stripper plate 8 of the upper mold contacts the multilayer printed wiring board 0 and stops.

Next, the outer die 7 of the upper mold descends.

At this time, a shearing force and a bending moment are generated on the outer shape processing cutting line 6 of the multilayer printed wiring board 0 by the lower die 9 and the outer die 7 of the upper die.

The bending moment is fixed by the upper mold stripper plate 8 and the lower mold die 9 and the outer mold die 7 of the upper mold and the outer stripper plate 10 of the lower mold. The outer shape is processed.

At this time, a bending moment is also generated in the vicinity of the contour cutting line 6 and extends from the contour cutting line 6 to the vicinity of the inside of the multilayer printed wiring board 0.

[0017]

However, in the external processing of the conventional multilayer printed wiring board 0 described above, after the upper die has descended onto the external processing cutting line 6, the desired external shape is produced by the shearing force with the lower die. The bending moment generated at this time reaches the inside of the multilayer printed wiring board 0, and the end portions 2 of the inner layer circuit patterns 2a and 2c formed below the inner layer circuit pattern 4a.
There is a problem that the maximum bending occurs on the tangents of b and 2d, the solder resist 5 on the outer circuit pattern 4a comes off, and the process yield deteriorates.

Furthermore, in recent build-up type high-density multilayer printed wiring boards having a small diameter conduction hole of 100 μm, the conduction hole near the end where the contour processing is formed due to the impact of the shearing force and the bending moment during the contour processing. And the possibility that cracks occur in the outermost insulating resin layer, which may impair the reliability of the multilayer printed wiring board.

The present invention solves the above-mentioned conventional problems. After the outer shape processing of the printed wiring board, the solder hole is peeled off on the outer shape processing cutting line and the vicinity thereof, or the conductive hole or the outermost layer near the outer shape forming end. It is an object of the present invention to reduce the possibility of cracks occurring in the insulating resin layer, and to improve the process yield and achieve stable quality.

[0020]

In order to achieve the above object, the present invention provides a multi-layer printed wiring board in which an inner layer pattern forming end is located between an outer layer pattern forming end and an outer shape forming end. Is to manufacture the multilayer printed wiring board formed in the above and perform the outer shape processing.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of a first embodiment of the present invention;
The invention according to claim 21 is to solve the conventional problem when the outer shape processing of the multilayer printed wiring board is press punching using a die, and the printed configuration is formed by forming the inner layer pattern. Is a multilayer printed wiring board formed so as to be located between the formation end of the outer layer pattern and the formation end of the outer shape processing.

Thus, when the multilayer printed wiring board set on the lower mold is cut on the contour processing line by lowering the upper mold, the shear force generated by the outer die of the upper mold and the die of the lower mold is reduced. The impact and bending moment can be absorbed and moderated at the formation end of the inner layer pattern.

Since the bending of the outer layer pattern and the insulating base material can be reduced by this action, the peeling of the solder resist on the outer layer pattern can be eliminated, and the impact of the insulating base material near the edge for forming the outer shape can be eliminated. Destruction can be minimized.

In particular, by forming the formation end of the inner layer pattern so as to be located at the midpoint between the formation end of the outer layer pattern and the formation end of the outer shape processing, the lamination of the inner layer substrate in the manufacturing process of the multilayer printed wiring board is performed. Even if the misalignment occurs in the direction of the outer shape forming end during alignment, the inner layer pattern forming end is not exposed from the outer shape forming wall surface, and even if the misalignment occurs in the opposite direction, the impact during outer shape processing And bending can be sufficiently absorbed and moderated.

[0025] Further, the printed wiring board, in which the insulating base material has flexibility and the bending moment during shearing is easily affected,
In a printed wiring board using a nonwoven fabric substrate resin laminate as an insulating substrate, it is effective in reducing the generation of fluffy fiber burrs on the processed wall surface.

Further, in recent years, a small-diameter hole is formed in a base material impregnated with an aramid nonwoven resin by using a laser, and a conductive material is filled in the through-hole to provide conduction of an inner layer pattern on both surfaces. After providing a small-diameter through-hole and alternately laminating and pressing copper foil on the outermost layer of an aramid nonwoven resin impregnated base material as a semi-cured insulating plate filled with conductive material, the outer layer pattern and solder resist The formed high-density and high-wiring-capacity multilayer printed wiring boards have attracted attention.

In a multilayer printed wiring board in which the small-diameter conductive holes of the outer layer and the inner layer are electrically connected by filling and hardening with a conductive material, the influence of the impact and bending moment upon the outer shape processing on the insulating substrate is minimized. The above configuration of the present invention works particularly effectively in ensuring the connection reliability of the conduction hole.

According to a second aspect of the present invention, the shape of the inner layer pattern forming end is made similar to the shape forming end of the outer shape processing, so that the outer shape processing end can be formed over a whole area or a partially wide area. Impact and bending can be absorbed and mitigated, and the concentration of impact force and stress due to the external processing shape can be prevented.

The invention according to claim 4 to claim 6, claim 8, claim 9, claim 18, and claim 19 of the present invention is characterized in that the presence of a plurality of inner-layer patterns reduces the impact and Bends can be absorbed and moderated, and the end of each inner layer pattern formed of multiple layers is formed at different positions, so that impact and bending during external processing can be efficiently absorbed and moderated stepwise. can do.

In particular, by forming the inner layer pattern forming end of the ground layer immediately below the surface on which the punching process is performed closer to the outer shape forming end side than the forming end of the power supply layer inner layer pattern, the efficiency is further improved. In addition to being able to efficiently absorb and mitigate the impact and bending during external processing in a stepwise manner, the position where the inner layer pattern forming end of the power supply layer is farther from the external processing end than the forming end of the ground layer inner layer pattern By doing so, electrical safety can be ensured.

In the structure of the present invention, the position of the formation end of the inner layer pattern is formed by using a design means, but in addition, a lamination method such as a mass lamination method which does not require relatively high alignment accuracy during lamination. In the above, it is also possible to adjust at the time of alignment of the lamination.

According to a tenth aspect of the present invention, the outer layer pattern forming end on the side opposite to the press punching surface is more than the outer layer pattern forming end on the press punching surface side.
By forming at a position close to the forming end of the outer shape processing, the impact and bending moment at the time of shearing of the outer shape processing can be absorbed and moderated even at the forming end of the outer layer pattern, and further by combining with the above-described configuration of the inner layer pattern. The effect can be further improved.

According to the present invention, the inner layer pattern has a plurality of independent circuits, and at least one of the independent circuits is formed on the outer shape forming end side. It is possible to cope with design constraints such as the layout of power supply layers and ground layers and wiring patterns, and adopts a configuration that is not electrically connected to other independent circuits. It is also possible to partially and locally enhance the absorption and relaxation of impacts and bending moments.

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a multilayer printed wiring board according to an embodiment of the present invention, and FIG. 2 shows a method of manufacturing a multilayer printed wiring board according to an embodiment of the present invention. 1 and 2, reference numeral 11 denotes a multilayer printed wiring board, 12a,
12c is the inner layer pattern, 12b and 12d are the formation ends of the inner layer pattern, 13a and 13c are the outer layer patterns, 13b and 1
3d is a forming end of the outer layer pattern, 14 is a solder resist,
15a to 15d are through holes, 16 is a conductive material, 17 is a formed end of external processing, 18a to 18c are insulating base materials, 19 is copper foil, 20 is a printed wiring board for an inner layer, 21 is a film, 2
Reference numeral 2 denotes an outline processing line.

The steps and configuration of the method for manufacturing the multilayer printed wiring board configured as described above will be described with reference to FIGS.

First, as shown in FIG. 2A, a film 21 made of a polyester-based resin was vacuum-laminated on both surfaces of a prepreg constituting a semi-cured insulating base material 18a impregnated with an aramid nonwoven fabric having plasticity. Thereafter, a through hole 15a having a predetermined diameter is formed by a means such as a laser beam such as carbon dioxide gas or excimer.

Next, the conductive material 16 is filled or applied to the through holes 15a formed in the insulating base material 18a and the film 21 by means such as a screen printing method, and then, as shown in FIG. The film 21 is peeled and removed, and a plurality of insulating base materials 18a are prepared.

Further, after vacuum laminating a film on both sides of the prepreg constituting the insulating base material 18b, through holes 15b and 15c having a predetermined diameter are formed, and the through holes 15b and 15c are formed.
After filling or applying the conductive material 16 to 15c, the film is peeled and removed to form an insulating base material 18b for the inner layer.

Next, copper foil 19 is applied to both sides of the insulating base material 18b for the inner layer by means such as hot pressing as shown in FIG.
Are laminated as shown in FIG.

Next, an etching resist is formed on the surface of the laminated copper foil 19 by using a photographic developing method or the like.

Further, the exposed copper foil on the surface on which the etching resist was not formed was removed by etching with a solution of cupric chloride or the like, and the etching resist was peeled off, as shown in FIG. The inner layer patterns 12a and 12c are formed on the insulating base material 18b.

The formation ends 12b and 12d of the inner layer pattern are connected to the formation ends 13b and 13d of the outer layer pattern.
A circuit is designed in advance so as to be located between d and the outline processing line 22, and they are formed by lamination.

In a multi-layer structure, the inner layer pattern 12a immediately below is used as a ground layer in the outer shape processing.
The other inner layer pattern 12c is formed as a power supply layer by circuit design in advance, and the formed end 12b of the inner layer pattern 12a is formed with the outer shape processing line 22d more than the formed end 12d of the inner layer pattern 12c.
Is obtained so that the printed wiring board 20 for the inner layer is formed so as to be close to the position.

Next, the copper foil 19 and the conductor 16 are connected to the through hole 1.
Insulating base material 18a for outer layer filled or applied to 5a
And printed wiring board 20 for inner layer and insulating base material 18c for outer layer
After combining with the copper foil 19, the layers are laminated while heating and pressurizing with a vacuum hot press machine to form a copper-clad multilayer insulating substrate as shown in FIG. 2 (e).

Further, after an etching resist for an outer layer is formed on the copper foil 19 of the copper-clad multilayer insulating substrate by using a photo-developing method or the like, the surface of the copper-clad multilayer insulating substrate on which the etching resist is not formed is dissolved by a solution such as cupric chloride. The exposed copper foil 19 is removed by etching, and the etching resist is stripped to form outer layer patterns 13a and 13c.

Next, a solder resist 14 is formed by using a method such as a screen printing method or a photographic developing method.
As shown in (f), the inner layer pattern forming ends 12b and 12d located between the outer layer pattern forming ends 13b and 13d and the outer shape processing line 22, the through holes 15a, 15b filled with or coated with the conductor 16 are formed. 15c and 15
The multilayer printed wiring board 11 formed by d is obtained.

The above-mentioned through holes 15a, 15b, 15c
And 15d filled the conductive material to form a conduction hole,
It may be formed by electroplating.

The above-described outer shape processing steps in the multilayer printed wiring board will be described with reference to FIGS. 3 (a) and 3 (b).

FIG. 3 (a) shows a configuration at the time of outer shape processing, where 51 is an outer die of an upper die, 52 is a stripper plate of an upper die, 53 is an outer die of a lower die, and 54 is an outer die of a lower die. The outer stripper plate of the lower die, 22 is the outer processing line, 56
Is a shearing force, 57 is a bending moment, and 11 is a multilayer printed wiring board.

Next, the outer shape processing of the multilayer printed wiring board will be described below.

FIG. 3 (b) shows the moment when the upper mold is lowered onto the multilayer printed wiring board set on the lower mold to perform the outer shape processing.

The multi-layer printed wiring board 11 is connected to the outer shape processing line 22.
When cutting above, the stripper plate 52 of the upper mold contacts the multilayer printed wiring board and stops.

Next, the outer die 51 of the upper mold descends.
At this time, the shearing force 56 and the bending moment 57 generated on and near the contour processing line 22 of the printed wiring board by the lower mold die 53 and the upper mold outer die 51 form the inner layer conductive patterns 12a and 12c. The presence of the ends 12b and 12d makes it possible to absorb and alleviate the impact and bending moment during the outer shape processing.

The inner layer conductor patterns 12a and 12c
By forming the formed ends 12b and 12d and the formed ends 13b and 13d of the outer layer conductor patterns 13a and 13c in a similar shape, it is possible to prevent the concentration of the impact force due to the outer shape.

Further, the inner layer conductor patterns 12a, 12
By forming one of the forming ends 12b and 12d of c so as to be located at the midpoint between the forming ends 13b and 13d of the conductor patterns 13a and 13c for outer layers and the outline processing line 22, a multilayer printed wiring board is manufactured. Even in the process of laminating / aligning the inner layer substrates, even if a misalignment occurs, it is possible to sufficiently absorb and mitigate the impact and bending during the outer shape processing.

Further, from the forming end 12c of the outer layer conductor pattern 12a on the press punching surface side, the forming end 13d of the outer layer conductor pattern 13c on the opposite side of the punching surface is formed at a position closer to the outer shape processing line 22. By doing so, the impact and bending moment at the time of external processing shearing are reduced to the formation ends 13b, 13 of the outer layer conductor patterns 13a, 13c.
Even d can be absorbed and relaxed.

By employing the multilayer printed wiring board having the above-mentioned structure, the peeling of the solder resist in the vicinity of the outer shape forming end can be eliminated, and the possibility of the occurrence of cracks in the through hole can be reduced.

Further, in the present embodiment, an example of a four-layer multilayer printed wiring board having a through hole filled with a conductive material has been described. As an application of this case, a build-up type multilayer printed wiring in which an insulating resin layer is applied and formed on the outermost layer of the four-layered multilayer printed wiring board, a non-through hole is provided in the insulating resin layer, and metal plating is applied thereto. The present invention is also effective for plates.

In this case, the possibility of cracks in the insulating resin layer can be reduced in addition to the solder resist and the conductive holes.

Embodiment 2 Hereinafter, another embodiment of the present invention will be described with reference to the drawings.

FIG. 4A is a perspective view of a printed wiring board for an inner layer in the multilayer printed wiring board according to the second embodiment, and FIG. 4B is a printed circuit board for an inner layer shown in FIG. It is a block diagram of a multilayer printed wiring board using a wiring board.

In FIG. 4A, reference numerals 71 to 74 denote independent circuits.

As shown in FIG. 4A, in the method for manufacturing a multilayer printed wiring board according to the second embodiment, when forming the printed wiring board for the inner layer, a plurality of independent circuits 71 to 7 are used.
4 is formed.

In FIG. 4B, reference numerals 80 to 83 denote conductor patterns for the inner layer, and reference numeral 84 denotes a contour processing line.

As described in the first embodiment, the layer structure of the multilayer printed wiring board having a plurality of inner layers is designed such that the inner conductor pattern immediately below the outer circuit pattern is a ground layer and the other is a power supply layer. May be restricted.

However, as shown in FIG. 4B, by forming at least one independent circuit on the outer shape processing line 84 side, the inner layer conductor pattern 80 immediately under the outer shape processing is formed.
Are formed as a ground layer, 81 as a power supply layer, the other inner layer conductor pattern 82 as a power supply layer, and 83 as a ground layer.
The circuit can be designed without any restrictions on the layout of the power supply layer and the ground layer and the design of the wiring pattern.

Further, by forming an independent circuit which is not electrically connected to other independent circuits on the side of the contour processing line 84, the impact and bending moment at the time of shearing during contour processing can be partially and locally absorbed. And the same effect as that described in the first embodiment can be obtained.

[0069]

As described above, the present invention can reduce the bending of the outer layer pattern and the insulating base material when the outer shape processing of the multilayer printed wiring board is performed by press punching using a die. Peeling of the upper solder resist can be eliminated, and cracking and destruction due to impact on the insulating base material, the insulating resin layer, and the conduction hole near the outer shape forming end can be minimized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a multilayer printed wiring board according to Embodiment 1 of the present invention.

FIG. 2 is a cross-sectional view illustrating a manufacturing process of the multilayer printed wiring board.

FIG. 3A is a cross-sectional view of the multilayer printed wiring board set on a lower mold. FIG. 3B is a cross-sectional view of the multilayer printed wiring board at the moment when the outer shape is cut.

FIG. 4A is a perspective view of an inner layer printed wiring board in a multilayer printed wiring board according to Embodiment 2 of the present invention. FIG. 4B is a configuration diagram of a multilayer printed wiring board using the inner layer printed wiring board.

FIG. 5 is a sectional view showing a configuration of a conventional multilayer printed wiring board.

6A is a cross-sectional view in which a conventional multilayer printed wiring board is set on a lower mold. FIG. 6B is a cross-sectional view at the moment when the conventional multilayer printed wiring board is cut out.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Multilayer printed wiring board 12a, 12c Inner layer conductor pattern 12b, 12d Inner layer conductor pattern forming end 13a, 13c Outer layer conductor pattern 13b, 13d Outer layer conductor pattern forming end 14 Solder resist 15a-15d Through hole 16 Conductor 17 Forming end of external processing 18a-18c Insulating base material 19 Copper foil 20 Printed wiring board for inner layer 21 Film 22,84 External processing line 51 Upper die outer die 52 Upper die stripper plate 53 Lower die outer shape Die 54 Lower die outer shape stripper plate 56 Shearing force 57 Bending moment 71-74 Independent circuit 80-83 Conductor pattern for inner layer

Continued on the front page (72) Inventor Kazutomo Higa 1006 Kadoma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. F term (reference) 5E346 BB11 CC05 CC32 DD44 FF18 GG08 GG14 GG15 GG24 GG26 GG28 HH31

Claims (21)

[Claims] In a multilayer printed wiring board having an outer layer pattern and an inner layer pattern formed on an insulating base material and subjected to an outer shape processing, an inner layer pattern forming end is located between an outer layer pattern forming end and an outer shape forming end. Multi-layer printed wiring board formed so as to be located in. 2. The multilayer printed wiring board according to claim 1, wherein the shape of the formation end of the inner layer pattern is similar to the shape of the formation end of the outer shape processing. 3. The multilayer printed wiring board according to claim 1, wherein the formation end of the inner layer pattern is formed at a midpoint between the formation end of the outer layer pattern and the formation end of the outer shape processing. 4. The multilayer printed wiring board according to claim 1, wherein the inner layer pattern is formed of a plurality of layers. 5. The multilayer printed wiring board according to claim 4, wherein formation ends of each inner layer pattern formed of a plurality of layers are formed at different positions. 6. An inner layer pattern of a plurality of layers is composed of a power supply layer dedicated to a power supply and a ground layer dedicated to an earth, and a forming end of the ground layer is closer to a forming end of the outer shape processing than a forming end of the power supply layer. 6. The method as claimed in claim 5, wherein the step is formed at a position.
2. The multilayer printed wiring board according to item 1. 7. The multilayer printed wiring board according to claim 1, wherein the external processing is press punching using a die. 8. The multilayer printed wiring board according to claim 7, wherein the formation end of the inner layer pattern immediately below the surface on which the punching process is performed is formed at a position close to the formation end side of the outer shape processing. The multilayer printed wiring board according to claim 5, wherein 9. The multilayer printed wiring board according to claim 8, wherein the inner layer pattern immediately below is a ground layer. 10. An outer layer pattern forming end opposite to the press punching surface is formed at a position closer to an outer shape forming end than an outer layer pattern forming end on the press punching surface side. Item 8. The multilayer printed wiring board according to item 7. 11. The multilayer printed wiring board according to claim 1, wherein the inner layer pattern is formed by a plurality of independent circuits. 12. The multilayer printed wiring board according to claim 11, wherein at least one of the plurality of independent circuits is formed on an outer shape forming end side. 13. The multilayer printed wiring board according to claim 12, wherein at least one independent circuit is not electrically connected to another independent circuit. 14. The multilayer printed wiring board according to claim 1, wherein the insulating base has flexibility. 15. The multilayer printed wiring board according to claim 1, wherein the insulating base has a structure in which a nonwoven fabric is impregnated with a resin. 16. The multilayer printed wiring according to claim 1, wherein the electrical connection between the outer layer pattern and the inner layer pattern is made by a conductive hole formed by filling and curing a conductive material in the through hole. Board. 17. A step of alternately laminating a copper foil on an outermost layer of a substrate for an inner layer having an inner layer pattern formed on an insulating base material and a semi-cured insulating plate, and press-bonding, and a step of forming an outer layer pattern And a step of forming a solder resist, and a method of manufacturing a multilayer printed wiring board having a step of forming an outer shape by punching out a mold, wherein the forming end of the inner layer pattern is formed between the forming end of the outer layer pattern and the forming end of the outer shape processing. A method for manufacturing a multilayer printed wiring board having an inner layer pattern formed so as to be located therebetween. 18. An inner layer pattern, wherein one of both surfaces of an inner layer substrate is a power supply layer and the other is formed as a ground layer, and the formation end of the ground layer is formed more externally than the formation end of the power supply layer. The method for manufacturing a multilayer printed wiring board according to claim 17, wherein the inner layer pattern is formed so as to be located at a position close to the end side. 19. The multilayer printed wiring board according to claim 17, wherein the ground layer of the inner layer substrate having the inner layer pattern according to claim 18 is laminated so as to be close to a die punching side. Method. 20. An inner layer substrate comprising: a step of providing a through hole in an insulating substrate; a step of filling a conductive material in the through hole; a step of laminating copper foil on both sides and heating and compressing the same; 18. The semi-cured insulating plate formed using a step of forming an inner layer pattern, wherein the semi-cured insulating plate is formed using a step of providing a through hole and a step of filling the through hole with a conductive material. A method for producing the multilayer printed wiring board according to the above. 21. The method according to claim 2, wherein the insulating substrate and the semi-cured insulating plate are aramid nonwoven resin-impregnated base materials, and the step of providing through holes is performed by laser.
0. The method for manufacturing a multilayer printed wiring board according to 0.