JP2021108321A - Printed-circuit board and method for manufacturing printed-circuit board - Google Patents

Abstract

To increase an amount of heat radiation from a solid pattern without increasing an occupied area of the solid pattern to a surface of an insulating layer and without using a component for heat radiation.SOLUTION: A printed-circuit board 100 (100A) comprises: an insulating layer 1; and a solid pattern 2 (2A) that is formed of a conductor on a surface 1a of the insulating layer 1, and has at least one type of a plurality of concave parts 2b and a plurality of convex parts 2e not penetrating in a thickness direction of the solid pattern 2 (2A) on an opposite side of a side of the solid pattern 2 (2A) in contact with the insulating layer 1.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a printed wiring board and a method for manufacturing a printed wiring board.

When electronic components are mounted on a printed wiring board and energized, the wiring generates heat due to the electrical resistance of the wiring.
This heat causes the temperature of the printed wiring board to rise excessively and becomes a factor that hinders the normal operation of electronic components.
In order to prevent an excessive temperature rise of the printed wiring board, it is necessary to increase the amount of heat radiated from the conductor layer of the printed wiring board to the atmosphere.
Therefore, conventionally, as described in Patent Document 1, for example, the area of the conductor layer is expanded, or parts for heat dissipation (heat sink, etc.) are provided on the printed wiring board to secure the required heat dissipation amount. rice field.

Japanese Unexamined Patent Publication No. 2011-096758

However, increasing the area of the conductor layer narrows the space for forming other wirings by that amount, which reduces the degree of freedom in designing the printed wiring board.
In addition, since the heat-dissipating parts are relatively large, there are restrictions on the installation location.
Further, since the heat-dissipating component is a component that is added separately from the electronic component, it becomes a factor that increases the manufacturing cost of the device.

In order to solve the above problems, the printed wiring board according to the present disclosure is
Insulation layer and
A solid pattern formed of a conductor on the surface of the insulating layer is provided.
The solid pattern has at least one of a plurality of concave portions and a plurality of convex portions that do not penetrate in the thickness direction of the solid pattern on the side opposite to the side in contact with the insulating layer.

In addition, the method for manufacturing one printed wiring board according to the present disclosure is as follows.
The first step of forming an etching resist on the surface of the conductor layer formed on the surface of the insulating layer, and
A second step of forming a plurality of holes penetrating in the thickness direction in a region of the etching resist that overlaps with a solid pattern portion of the conductor layer.
The present invention includes a third step of forming a plurality of recesses on the surface of the solid pattern by etching the conductor layer through the etching resist in which the plurality of holes are formed.

In addition, other methods for manufacturing printed wiring boards according to the present disclosure are described.
The sixth step of forming a plating resist on a flat solid pattern formed on the surface of the insulating layer, and
A seventh step of forming a plurality of holes penetrating in the thickness direction in a region of the plating resist that overlaps with the flat solid pattern by exposing and developing the plating resist.
The eighth step of forming a plurality of convex portions on the surface of the flat solid pattern by performing electrolytic copper plating on the surface of the flat solid pattern through the plating resist in which the plurality of holes are formed. include.

According to the present disclosure, it is possible to increase the amount of heat radiation of the solid pattern without increasing the area occupied by the solid pattern with respect to the surface of the insulating layer and without using heat-dissipating parts.

It is a perspective view which shows a part of the printed wiring board which concerns on 1st Embodiment of this disclosure. FIG. 2 is a cross-sectional view taken along the line II-II of the printed wiring board of FIG. FIG. 3 is a cross-sectional view taken along the line III-III of the printed wiring board of FIG. It is sectional drawing which shows the state in the manufacturing process of the printed wiring board of FIG. It is sectional drawing which shows the state in the manufacturing process of the printed wiring board of FIG. It is a perspective view which shows a part of the printed wiring board which concerns on 2nd Embodiment of this disclosure. It is VII-VII sectional view of the printed wiring board of FIG. It is VIII-VIII sectional view of the printed wiring board of FIG. It is sectional drawing which shows the state in the manufacturing process of the printed wiring board of FIG. It is sectional drawing which shows the state in the manufacturing process of the printed wiring board of FIG.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.
However, the technical scope of the present disclosure is not limited to those illustrated in the following embodiments and drawings.

<1. First Embodiment>
First, the first embodiment of the present disclosure will be described.

[1-1. Configuration of printed wiring board]
First, the configuration of the printed wiring board 100 according to the present embodiment will be described.
FIG. 1 is a perspective view showing a part of the printed wiring board 100 according to the present embodiment, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional view taken along line III-III of FIG.

As shown in FIG. 1, the printed wiring board 100 includes an insulating layer 1 and a solid pattern 2.
Further, the printed wiring board 100 according to the present embodiment includes another wiring pattern (similar to the other wiring pattern 2D in the second embodiment described later).

The insulating layer 1 is formed of an insulating material (for example, glass woven cloth, epoxy resin, etc.) in a flat plate shape.

The solid pattern 2 is formed of a conductor on the surface of the insulating layer 1 (hereinafter, the first surface 1a).
The solid pattern 2 according to this embodiment is used for ground or power supply.
The conductor is, for example, copper.
The preferable range of the thickness t of the solid pattern 2 according to the present embodiment is 30 μm or more.
The thickness t here is the thickness of the portion of the solid pattern 2 that does not have the recess 2b, which will be described later.

The solid pattern 2 has a plurality of recesses 2b on the side of the surface opposite to the side in contact with the insulating layer 1.
Specifically, the surface of the solid pattern 2 opposite to the side in contact with the insulating layer 1 (hereinafter referred to as the second surface 2a) has a plurality of recesses 2b.

Each recess 2b is spherical.
That is, each opening 2c is circular.
Further, the cross section of the recess 2b when cut in a plane passing through the center of the opening 2c and orthogonal to the first surface 1a is semicircular as shown in FIG.

Each recess 2b does not penetrate in the thickness direction of the solid pattern 2.
That is, the depth d of the recess 2b is equal to or less than the thickness t of the solid pattern 2.
Further, the radius r of the opening 2c of the recess 2b is equal to or less than the thickness t of the solid pattern 2.
The radius r of the opening 2c and the depth d of the recess 2b may be equal to each other.
Further, the radius r of the recess 2b may be larger than the depth d, or the depth d may be larger than the radius r.
Also, not all recesses 2b need to be the same size. That is, at least one of the radius r and the depth d of the opening 2c of the part of the recess 2b may be larger or smaller than the radius r and the depth d of the opening 2c of the other recess 2b.

As shown in FIG. 1, the plurality of recesses 2b according to the present embodiment when viewed from a direction orthogonal to the first surface 1a are arranged in a matrix.
Further, the plurality of recesses 2b are arranged so as to be distributed over the entire second surface 2a of the solid pattern 2.
The arrangement of the plurality of recesses 2b is not limited to a matrix shape, and may have a certain regularity such as a staggered shape.
As shown in FIG. 3, the preferable range of the distance i between the adjacent recesses 2b and the recesses 2b is the diameter of the opening 2c (twice the radius r) or more.
The distance i between all the recesses 2b and the recesses 2b does not have to be uniform. That is, the distance i between a part of the recesses 2b and the recesses 2b may be larger or smaller than the distance i.

The other wiring pattern is formed of a conductor in a region of the first surface 1a of the insulating layer 1 where the solid pattern 2 is not formed.

The surface area of the sphere is greater than the area of a circle of equal radius.
Therefore, in the printed wiring board 100 configured as described above, the surface area of the solid pattern 2 is larger by the amount of the recess 2b than that of a flat surface having a simple second surface 2a.
The amount of heat dissipated from the conductor is proportional to the surface area of the conductor. Therefore, the amount of heat radiated from the solid pattern 2 is larger than that in which the area occupied by the insulating layer 1 is the same and the recess 2b is not provided.
Therefore, according to the printed wiring board 100 according to the present embodiment, the amount of heat radiated from the solid pattern 2 is increased without increasing the area occupied by the solid pattern 2 with respect to the surface of the insulating layer 1 and without using heat radiating parts. Can be made to.

[1-2. Manufacturing method of printed wiring board]
Next, a method of manufacturing the printed wiring board 100 will be described.
4 and 5 are cross-sectional views showing a state in which the printed wiring board 100 is in the process of being manufactured.

The method for manufacturing the printed wiring board 100 according to the present embodiment includes a pre-plating step, a plating step, a resist forming step, a hole forming step, an opening forming step, an etching step, and a resist peeling step.
Further, in the manufacturing method according to the present embodiment, the printed wiring board 100 is manufactured using the copper-clad laminate 100B.

As shown in FIG. 4A, the copper-clad laminate 100B used here has an insulating layer 1 and a copper foil 21.
The insulating layer 1 corresponds to the insulating layer 1 in the printed wiring board 100.
The copper foil 21 is formed on the entire surface of the first surface 1a of the insulating layer 1.
The thickness of the copper foil 21 according to this embodiment is 18 μm.

In the first pre-plating step (fourth step), the copper foil 21 formed on the first surface 1a of the insulating layer 1 of the copper-clad laminate 100B is etched as a pre-plating treatment.
In the pre-plating step according to the present embodiment, the surface layer portion of the copper foil 21 up to a depth of about 3 μm is removed from the surface. This makes it possible to remove the metal oxide and prepare the surface of the copper foil.

After etching the copper foil 21, the process proceeds to the plating step (fifth step).
In the plating step, the surface of the pre-plated copper foil 21 is plated to form a conductor layer 2B composed of the copper foil 21 and the plating layer 22, as shown in FIG. 4A.
In the plating step according to the present embodiment, the thickness of the plating layer 22 is set to 15 μm or more. As a result, the conductor layer 2B having a thickness t of 30 μm or more is formed. The thickness of the plating layer 22 is set to 15 μm or more in order to ensure the continuity of through holes and vias (not shown).

After forming the conductor layer 2B, the process proceeds to a resist forming step (first step).
In the resist forming step, as shown in FIG. 4B, the surface of the conductor layer 2B formed on the first surface 1a of the insulating layer 1 opposite to the side in contact with the insulating layer 1 (hereinafter referred to as the third surface 2a1). to form the etching resist _{R 1.}
In the resist forming step according to the present embodiment, a photosensitive dry film is laminated on the third surface 2a1 of the conductor layer 2B.
In the resist forming step according to the present embodiment, a dry film in which _{the surface of the main body R 11} is covered with the cover R _{12 is laminated.}

After forming the etching resist R ₁ , the process proceeds to the hole forming step (second step).
The hole forming step, the etching resist R _1, in a region overlapping with the region to be solid pattern 2 of the conductive layers 2B, forming a plurality of holes Ra penetrating in the thickness direction.
The hole forming step according to the present embodiment, as shown in FIG. 4 (c), to form a plurality of holes Ra by prick pins P on the etching resist R _1.
The thickness of the pin P is made smaller than the diameter of the opening 2c of the recess 2b to be formed.
Here, a plurality of pins P may be pierced at the same time, or a plurality of pins P less than the number of formed 1 or holes Ra may be pierced a plurality of times.
Further, in the hole forming step according to the present embodiment, the pin P _{is pierced from above the cover R 12.}

Further, after forming a plurality of holes Ra in the etching resist R ₁ , the process proceeds to the opening forming step.
In the opening forming step, by exposing the etching resist R ₁ development, the etching resist R _1, to form an opening for forming at least a solid pattern 2.
In the opening forming step according to the present embodiment, an opening for forming another wiring pattern is formed together with an opening for forming the solid pattern 2.
Since the dry film is a negative type resist, a portion of the dry film that forms the solid pattern 2 and other wiring patterns is exposed and developed. As a result, an opening is formed in the portion of the dry film that overlaps with the portion of the conductor layer 2B to be removed.
The opening formation step may be performed before the etching step, and may be before the hole forming step, but may be after the hole forming step. Incidentally, it is after the hole forming step, in the handling of the hole forming step, in order to hardly scratched etching resist R _1.

After forming the plurality of holes Ra, the process proceeds to the etching step (third step).
In the etching step, a plurality of recesses 2b are formed on the third surface 2a1 of the conductor layer 2B by etching the conductor layer 2B through _{the etching resist R 1} (main body R ₁₁ ) in which a plurality of holes Ra are formed.
As shown in FIG. 5A, the conductor layer 2B is etched radially from the portion in contact with the etching solution.
Further, in the etching step according to the present embodiment, before the bottom of the recess 2b reaches the boundary surface between the insulating layer 1 and the solid pattern 2 (the depth d of the recess 2b becomes larger than the thickness t of the conductor layer 2B). Finish the etching.
This is because when the bottom of the recess 2b reaches the boundary surface between the insulating layer 1 and the solid pattern 2, the bottom of the recess 2b is no longer a conductor (the insulating layer 1 is exposed), so that the surface area of the inner surface of the recess 2b is increased by that amount. This is because it will decrease.
After etching, at least a solid pattern 2 is formed on the first surface 1a of the insulating layer 1, and as shown in FIG. 5B, the third surface 2a1 of the solid pattern 2 has a plurality of recesses 2b. It becomes.

After forming the recess 2b, the process proceeds to the resist peeling step.
The resist stripping step, as shown in FIG. 5 (c), separating the etching resist R ₁ from the solid pattern 2 and other wiring patterns (peeling body R ₁₁ of the dry film).
In this way, the printed wiring board 100 according to the present embodiment is manufactured.

It is also possible to form the hole Ra without using the pin P.
In that case, after the resist forming step, the hole forming step is skipped and the opening forming step is started. Then, in the opening forming step, _{by exposing and developing the etching resist R 1} , a plurality of holes Ra are formed at the same time as the opening for forming the solid pattern 2.
In this way, the manufacturing process of the printed wiring board 100 can be simplified.

<2. Second Embodiment>
Next, the second embodiment of the present disclosure will be described.
In addition, here, the same reference numerals are given to the configurations common to the above-described embodiments, and the description thereof will be omitted.

[2-1. Configuration of printed wiring board]
First, the configuration of the printed wiring board 100A according to the present embodiment will be described.
6 is a perspective view showing a part of the printed wiring board 100A according to the present embodiment, FIG. 7 is a sectional view taken along line VII-VII of FIG. 6, and FIG. 8 is a sectional view taken along line VIII-VIII of FIG.

The shape of the solid pattern 2A of the printed wiring board 100A according to the present embodiment is different from that of the first embodiment.
That is, as shown in FIG. 6, the solid pattern 2A according to the present embodiment has a plurality of convex portions 2e on the side opposite to the side in which the insulating layer 1 is in contact.
Specifically, the surface of the solid pattern 2A opposite to the side in contact with the insulating layer 1 (hereinafter referred to as the fourth surface 2d) has a plurality of convex portions 2e.

The shape of each convex portion 2e is columnar.
The shape of the convex portion 2e according to the present embodiment is a columnar shape.
That is, the upper surface 2f of the convex portion 2e is circular.
Further, as shown in FIG. 7, the side surface 2g of the convex portion 2e is orthogonal to the first surface 1a.
Further, the width w of the convex portion 2e is equal at any height.
The convex portion 2e does not have to have a perfect columnar shape. For example, the thickness may be different between the upper part and the lower part. The upper end may be rounded or may have a shape close to a cone.

The height h of the convex portion 2e is 15 μm or more.
The height h and the width w of the convex portion 2e according to the present embodiment are equal to each other.
By having such a height h and a width w, the convex portion 2e can efficiently dissipate heat.
The height h of the convex portion 2e may be larger than the width w, or may be larger than the height h of the width w.
Further, the plurality of convex portions 2e do not have to be all the same size. That is, at least one of the width w and the height h of the part of the convex portion 2e may be larger or smaller than the width w and the height h of the other convex portion 2e.

As shown in FIG. 6, the plurality of convex portions 2e according to the present embodiment when viewed from a direction orthogonal to the first surface 1a are arranged in a matrix.
Further, the plurality of convex portions 2e are arranged so as to be distributed over the entire fourth surface 2d of the solid pattern 2A.
The arrangement of the convex portions 2e is not limited to a matrix shape, and may have a certain regularity such as a staggered shape.
As shown in FIG. 8, the preferable range of the distance i between the adjacent convex portions 2e and the convex portions 2e is the width w or more of the convex portions 2e.
The distances i between all the convex portions 2e and the convex portions 2e do not have to be uniform. That is, the distance i between a part of the convex portion 2e and the convex portion 2e may be larger or smaller than the above distance i.

The surface area of the convex portion 2e of the cylinder is larger than the area of the circle congruent with the bottom surface by the amount of the side surface 2g.
Therefore, in the printed wiring board 100A configured as described above, the surface area of the solid pattern 2A is larger by the amount of the convex portion 2e than that of the flat surface having the fourth surface 2d.
Therefore, the amount of heat radiated from the solid pattern 2A is larger than that in which the area occupied by the insulating layer 1 is the same and the convex portion 2e is not provided.
Therefore, according to the printed wiring board 100A according to the present embodiment, the amount of heat radiated from the solid pattern 2A is increased without increasing the area occupied by the solid pattern 2A with respect to the surface of the insulating layer 1 and without using heat radiating parts. Can be made to.

[2-2. Manufacturing method of printed wiring board]
Next, a method of manufacturing the printed wiring board 100A will be described.
9 and 10 are cross-sectional views showing a state in which the printed wiring board 100A is being manufactured.

The method for manufacturing the printed wiring board 100A according to the present embodiment includes a pattern forming step, a resist forming step, a hole forming step, a plating step, and a resist peeling step.

In the first pattern forming step, as shown in FIG. 9A, a flat solid pattern 2C and another wiring pattern 2D are formed on the first surface 1a of the insulating layer 1.
This flat solid pattern 2C will later become the solid pattern 2A according to the present embodiment. This flat solid pattern 2C does not yet have the convex portion 2e, and the surface opposite to the side in contact with the insulating layer 1 (hereinafter, the fifth surface 2d1) is flat.
In the manufacturing method according to the present embodiment, the flat solid pattern 2C and the other wiring pattern 2D (not shown) can be formed by any method. That is, any of the subtractive method, the semi-additive method, and the MSAP (Modified Semi-Additive Process) can be used.

When the subtractive method is used in this pattern forming step, plating leads are formed at the same time as 2C such as a flat solid pattern.
This plating lead is for securing a power source when performing electrolytic copper plating in the plating process described later.
On the other hand, when the semi-additive method or MSAP is used in the pattern forming step, the seed layer used for forming the flat solid pattern 2C or the like is used to secure a power source when performing electrolytic copper plating in the plating step described later.

After forming the flat solid pattern 2C, the process proceeds to the resist forming step (sixth step).
In the resist forming step, as shown in FIG. 9 (b), to form a plating resist R ₂ Fifth surface 2d1 of at least flat solid pattern 2C formed on the first surface 1a of the insulating layer 1.
In the resist forming step according to the present embodiment, a photosensitive dry film is laminated on the surface of another wiring pattern 2D and the fifth surface 2d1 of the flat solid pattern 2C.
Further, in the resist forming step according to the present embodiment, the thickness of the dry film used is 25 μm.

After forming the plating resist R ₂ proceeds to hole forming step (seventh step).
Multiple this hole forming step, by developing exposed plating resist R _2, as shown in FIG. 9 (c), the plating resist R _2, in a region overlapping with the flat solid pattern 2C, penetrating in the thickness direction Hole Rb is formed.
Since the dry film is a negative type resist, a portion of the dry film that does not form pores Rb is exposed and developed. As a result, holes Rb are formed in the portion of the dry film that forms the convex portion 2e.
In the hole forming step according to the present embodiment, a circular hole is formed as the hole Rb.
The diameter of each hole Rb to be formed is equal to the width w of the convex portion 2e to be formed.

Further, in the hole forming step according to the present embodiment, the arrangement of the plurality of holes Rb when viewed plating resist R ₂ from a direction perpendicular to its surface, is equal to the sequence of the projecting portion 2e.
Further, in the hole forming step according to the present embodiment, the distance between the hole Rb and the hole Rb is set to be equal to or larger than the diameter of the hole Rb. That is, the distance i between the convex portion 2e and the convex portion 2e formed in the plating step described later is set to be equal to or larger than the width w of the convex portion 2e.
This is because when the distance between the holes Rb and hole Rb is narrower than the diameter of the hole Rb, the contact area of the plating resist R ₂ and its base (where flat solid pattern 2C) between the hole Rb and hole Rb smaller becomes excessively, the plating resist R ₂ in the plating is because there is a possibility that the detached from the ground.

Incidentally, in the plating step to be described later, in addition to the convex portions 2e, if the other components of the wiring pattern (e.g. pad component mounting) formed by plating is in the plating resist R _2, other conductor layer 2B An opening for forming another component is also formed in a region overlapping the portion to be a component.

After forming a plurality of holes Rb the plating resist R _2, moves to the plating step (Eighth step).
Site in the plating process, through the plating resist R ₂ in which a plurality of said holes Rb is formed by performing electrolytic copper plating to the fifth surface 2d1 of the flat solid pattern 2C, exposed from the hole Rb of the fifth surface 2d1 A plurality of convex portions 2e are formed on the surface.
In this plating step, when the other components of the wiring pattern are formed by plating together with the convex portion 2e, the thickness of the other components needs to be 15 μm or more. Therefore, when forming other components, the height h of the convex portion 2e formed at the same time is also 15 μm or more.

Further, in the plating step according to the present embodiment, plating is performed before the upper surface 2f of the _{convex portion 2e reaches the surface of the plating resist R 2} (the height h of the convex portion 2e becomes larger than the thickness of the _{plating resist R 2).} Finish.
This is because, when the height h of the convex portion 2e is greater than the thickness of the plating resist R _2, part beyond the surface of the plating resist R ₂ in the convex portion 2e is spread in the width direction, the plating resist R ₂ is convex portion 2e This is because it gets caught in.
When a plating lead is formed in the pattern forming step described above, the plating lead is removed by cutting or etching at the end of the plating step.
After plating, as shown in FIG. 10A, the fifth surface 2d1 of the flat solid pattern 2C becomes the fourth surface 2d having a plurality of recesses 2b.

After forming the convex portion 2e, the process proceeds to the resist peeling step.
The resist stripping step, as shown in FIG. 10 (b), peeling the plating resist R ₂ from solid pattern 2A and the other wiring patterns (peeling the dry film).
In this way, the printed wiring board 100A according to the present embodiment is manufactured.

<3. Others>
The printed wiring boards 100 and 100A need only have at least one of a plurality of concave portions 2b and a plurality of convex portions 2e in the solid patterns 2 and 2A, and the solid patterns 2 and 2A have the concave portions 2b and the convex portions 2e. You may have both.
Further, the printed wiring boards 100 and 100A may include both a solid pattern 2 having only the concave portion 2b and a solid pattern 2A having only the convex portion 2e.

100,100A Printed wiring board 1 Insulation layer 1a First surface (surface of insulation layer)
2,2A Solid pattern 2a Second surface 2b Recessed surface 2c Opening 2d Fourth surface 2e Convex part 2f Top surface 2g Side surface 21 Copper foil 22 Plating layer 100B Copper-clad laminate 2B Conductor layer 2a1 Third surface 2C Flat solid pattern 2d1 Fifth surface 2D Wiring pattern P Pin R ₁ Etching resist R ₁₁ Main body R ₁₂ Cover Ra Hole R ₂ Plating resist Rb Hole i Distance between recesses (convex and convex) r Radius of recess opening radius h Convex height W The width of the convex part d The depth of the concave part t The thickness of the solid pattern

Claims (17)

Insulation layer and
The insulating layer is provided with a solid pattern formed of a conductor.
A printed wiring board having at least one of a plurality of concave portions and a plurality of convex portions that do not penetrate in the thickness direction of the solid pattern on the side of the solid pattern opposite to the side in contact with the insulating layer. The printed wiring board according to claim 1, wherein the recess is a spherical surface. The printed wiring board according to claim 1 or 2, wherein the depth of the recess and the radius of the opening are equal to or less than the thickness of the solid pattern. The printed wiring board according to any one of claims 1 to 3, wherein the distance between the adjacent recesses is equal to or larger than the diameter of the opening of the recess. The printed wiring board according to any one of claims 1 to 4, wherein the solid pattern has a thickness of 30 μm or more. The printed wiring board according to claim 1, wherein the shape of the convex portion is columnar. The printed wiring board according to claim 1 or 6, wherein the distance between the adjacent convex portions is equal to or greater than the width of the convex portions. The printed wiring board according to claim 1, claim 6 or claim 7, wherein the height of the convex portion is equal to the width of the convex portion. The printed wiring board according to claim 1, claim 6, claim 7, or claim 8, wherein the height of the convex portion is 15 μm or more. The first step of forming an etching resist on the surface of the conductor layer formed on the surface of the insulating layer, and
A second step of forming a plurality of holes penetrating in the thickness direction in a region of the etching resist that overlaps with a solid pattern portion of the conductor layer.
A method for manufacturing a printed wiring board, comprising a third step of forming a plurality of recesses on the surface of the conductor layer by etching the conductor layer through the etching resist in which the plurality of holes are formed. The method for manufacturing a printed wiring board according to claim 10, wherein in the second step, a plurality of the holes are formed by piercing the etching resist with a pin. The printed wiring according to claim 10 or 11, wherein an opening for forming at least the solid pattern is formed in the etching resist by exposing and developing the etching resist before moving to the third step. How to make a board. The method for manufacturing a printed wiring board according to claim 10, wherein in the second step, a plurality of the holes are formed by exposing and developing the etching resist. The method for manufacturing a printed wiring board according to claim 12, wherein in the second step, the etching resist is exposed and developed to form an opening for forming at least the solid pattern together with the plurality of holes. The method for manufacturing a printed wiring board according to claim 10, wherein in the third step, etching is completed before the bottom of the recess reaches the boundary surface between the insulating layer and the solid pattern. Prior to the first step, a fourth step of etching the copper foil formed on the surface of the insulating layer as a pre-plating treatment,
A fifth step of forming the conductor layer having a total thickness of 30 μm or more, which is composed of the copper foil and a plating layer having a thickness of 15 μm or more, by plating the surface of the copper foil which has been pre-plated. The method for manufacturing a printed wiring board according to claim 10 or 11, further comprising. The sixth step of forming a plating resist on a flat solid pattern formed on the surface of the insulating layer, and
A seventh step of forming a plurality of holes penetrating in the thickness direction in a region of the plating resist that overlaps with the flat solid pattern by exposing and developing the plating resist.
The eighth step of forming a plurality of convex portions on the surface of the flat solid pattern by performing electrolytic copper plating on the surface of the flat solid pattern through the plating resist in which the plurality of holes are formed. Manufacturing method of printed wiring board including.

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