JP2022093713A - Printed circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printed circuit board.

SOLUTION: A printed circuit board includes: a first insulating layer formed with a penetration hole; a second insulating layer that covers both surfaces of the first insulating layer, and having a rigidity lower than that of the first insulating layer; a magnetic core arranged in the penetration hole; and a coil pattern formed on one and the other surfaces of the second insulating layer so as to be wound around the magnetic core. The magnetic core includes: a first support layer arranged so as to surround the first insulating layer; and a first magnetic layer formed on one surface of the first support layer so as to surround the first insulating layer.

SELECTED DRAWING: Figure 1a

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a printed circuit board (printed circuit board).

The inductor is a passive element that is built into an electronic product to remove noise or is one of the electronic components constituting an LC resonance circuit or the like and constitutes an electronic circuit.
On the other hand, due to the tendency of electronic devices to become smaller and thinner, the power signal transmission characteristics of circuit boards built in electronic devices are also becoming important.
As a result, in order to improve the power signal transmission characteristics of the circuit board, a technique for incorporating an inductor inside the printed circuit board has been developed.

As a technique for incorporating an inductor in a circuit board, there is a method of forming a coil pattern in an insulating layer and forming the coil pattern by using a conductor pattern forming technique of the circuit board such as a method of connecting the coil patterns with vias.

Korean Publication No. 2013-0140431 Gazette

In the printed circuit board according to one aspect of the present invention, the impedance characteristics can be improved by including the magnetic core wound by the coil pattern on one or both sides of the support layer and the support layer.

It is a figure which shows schematic cross section of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows roughly the part of the plane of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows schematic cross section of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows schematic cross section of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows schematic cross section of the printed circuit board which concerns on 4th Embodiment of this invention. It is a figure which shows schematic cross section of the printed circuit board which concerns on 5th Embodiment of this invention. It is a figure which shows schematic cross section of the printed circuit board which concerns on 6th Embodiment of this invention. It is a figure which shows schematic cross section of the printed circuit board which concerns on 7th Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on one Example of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on one Example of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on one Example of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on one Example of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on one Example of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on other Examples of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on other Examples of this invention. It is a figure which shows the manufacturing method of the magnetic core which concerns on other Examples of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 2nd Embodiment of this invention. It is a figure which shows the modification of the 2nd Example of this invention. It is a figure which shows the modification of the 2nd Example of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention. It is a figure which shows the manufacturing method of the printed circuit board which concerns on 3rd Embodiment of this invention.

The terms used in this application are used solely to illustrate specific embodiments and are not intended to limit the invention. A singular expression contains multiple expressions unless explicitly expressed in a sentence.

In the present application, when a part "contains" a component, it means that the other component can be further included without excluding the other component unless otherwise specified.

Also, throughout the specification, "above" means to be located above or below the target portion, not necessarily above it with respect to the direction of gravity.

Further, "bonding" does not mean only the case where each component is in direct physical contact with each other in the contact relationship between the components, and other components intervene between the components. It is used as a concept that includes the case where each component is in contact with the other configuration.

The terms first, second and the like are used to describe various components, but the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from the other.
The sizes and thicknesses of the configurations shown in the drawings are arbitrary for convenience of explanation, and the present invention is not necessarily limited thereto.

Hereinafter, examples of the printed circuit board according to the present invention will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be designated by the same drawing reference numerals in the description with reference to the attached drawings. , The duplicate explanation for this is omitted.

(Printed circuit board)
(First Example)
FIG. 1a is a diagram schematically showing a cross section of a printed circuit board according to a first embodiment of the present invention.
FIG. 1b is a diagram schematically showing a part of a flat surface of a printed circuit board according to a first embodiment of the present invention.

Referring to FIGS. 1a and 1b, the printed circuit board 100 according to the first embodiment of the present invention includes a first insulating layer 10, a second insulating layer 20, a coil pattern 40, and a magnetic core 50. The magnetic core 50 includes a first support layer S1, a first magnetic layer M1, and a second magnetic layer M2.

The first insulating layer 10 has a higher rigidity than the second insulating layer 20. That is, the first insulating layer 10 may be a core insulating layer that can be normally used in the field to which the printed circuit board 100 according to the present embodiment belongs, and the second insulating layer 20 may be an ABF (Ajinomoto Buildup) in the core insulating layer. It may be a build-up insulating layer formed by laminating Film) or the like.

The first insulating layer 10 may be a prepreg in which glass fiber or glass cloth is impregnated with an insulating resin. The second insulating layer 20 may be made of an insulating resin, or may contain an inorganic filler such as silica in the insulating resin.
The through hole C penetrates the first insulating layer 10. A magnetic core 50 is arranged in the through hole C.

In the printed circuit board 100 according to the present embodiment, the through hole C is formed in the first insulating layer 10, and then the magnetic core 50 is arranged so as to be embedded in the through hole C, so that the magnetic core is magnetic on the insulating layer. Damage to the substrate can be minimized compared to the prior art in which the core is placed.

In the structure of a conventional thin film inductor in which a coil pattern is wound around a magnetic core, a part of the magnetic thin film is etched in the insulating layer on which the magnetic thin film is formed, so that the insulating layer is formed during the etching process. May be damaged by strong acids such as hydrofluoric acid or nitric acid.

In the printed circuit board 100 according to the present embodiment, the magnetic core 50 formed through a process different from the substrate forming step is arranged in the through hole C of the first insulating layer 10. That is, the printed circuit board 100 according to the present embodiment does not directly form the magnetic core 50 on the first insulating layer 10.

Therefore, the printed circuit board 100 according to the present embodiment does not have the above-mentioned problems caused by forming the magnetic core in the insulating layer. Further, the printed circuit board 100 according to the present embodiment is not affected by the target size of the sputtering equipment required for forming the magnetic core, and can form the printed circuit board containing the magnetic core.

The magnetic core 50 according to an embodiment of the present invention includes a first support layer S1 and a first magnetic layer M1 and a second magnetic layer M2 formed on one surface and the other surface of the first support layer S1, respectively. Can be done.

The thicker the magnetic core 50, the better the magnetic permeability, and the stronger the magnetic flux, the better the performance of the printed circuit board. However, it is not preferable to form the magnetic core 50 with a certain thickness or more because of the problem of adhesive force with the resin and the like.

Therefore, in the magnetic core 50 applied to this embodiment, the first magnetic layer M1 is formed on one surface of the first support layer S1, and the second magnetic layer M2 is formed on the other surface of the first support layer S1. Thereby, the thickness of the magnetic layer contained in the magnetic core 50 can be formed to be thicker.

Specifically, the thickness of the first magnetic layer M1 that can be formed on one surface of the first support layer S1 is formed to the maximum height, and then the second magnetic layer is formed on the other surface of the first support layer S1 by the same method. If the thickness of M2 is formed to the maximum height, magnetic layers can be formed on both sides of the first support layer S1, whereby the thickness of the magnetic layer formed on the magnetic core 50 is formed to be thicker. can do.
On the other hand, the thickness of the first support layer S1 may be different in consideration of the thickness of the first magnetic layer M1, the thickness of the second magnetic layer M2, the height of the first insulating layer 10, and the like. can.

As the first support layer S1, a wafer substrate, a Cu / foil-etched unclad substrate in CCL, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, a glass epoxy substrate, a polyester substrate and the like can be used.

The material constituting the first magnetic layer M1 and the second magnetic layer M2 is at least one magnetic material selected from the group consisting of Ni-based ferrite, Ni—Zn-based ferrite, and Ni—Zn—Cu-based ferrite. Can be configured.
The printed circuit board 100 according to the present embodiment includes a coil pattern 40 formed on one surface and the other surface of the second insulating layer 20 and wound around the magnetic core.

Referring to FIGS. 1a and 1b, the coil pattern 40 interconnects the first conductor pattern 41, which is formed on one surface and the other surface of the second insulating layer 20 so as to be separated from each other, and the first conductor pattern 41. Therefore, the coil via 42 penetrating the first insulating layer 10 and the second insulating layer 20 is included.

As shown in FIG. 1b, a plurality of first conductor patterns 41 are formed on one surface of the second insulating layer 20, and after being formed on the other surface of the second insulating layer 20, they are connected by the coil via 42. It is possible to embody the form in which the magnetic core 50 is wound by the coil pattern 40.
Therefore, the magnetic permeability can be improved by forming the coil pattern 40 more finely and forming the first conductor pattern 41 more.

Further, the printed circuit board 100 according to the present embodiment includes a solder resist layer 70 including an opening in order to enable electrical connection between the first conductor pattern 41 and an electronic element while protecting the first conductor pattern 41. Further can be included.

On the other hand, the magnetic core 50 inserted into the printed circuit board 100 according to the present embodiment can form the magnetic layer M1 only on one surface of the support layer S1, and is limited to the example in which the magnetic layers are laminated on both sides. There is no such thing.

(Second Example)
FIG. 2 is a diagram schematically showing a cross section of a printed circuit board according to a second embodiment of the present invention. In explaining the printed circuit board according to the second embodiment of the present invention, the description of the portion overlapping with the first embodiment will be omitted.

Referring to FIG. 2, the magnetic core 50 inserted into the printed circuit board 200 according to the present embodiment includes a first magnetic layer M1, a first support layer S1, a second magnetic layer M2, and a second support layer S2. And the third magnetic layer M3 can be included.

In the magnetic core 50 applied to this embodiment, support layers S1 and S2 are formed between adjacent magnetic layers M1, M2 and M3. That is, the first support layer S1 is formed between the first magnetic layer M1 and the second magnetic layer M2, and the second support layer S2 is formed between the second magnetic layer M2 and the third magnetic layer M3. ..

In order to reduce the overall thickness of the magnetic core 50 while increasing the number of magnetic layers formed on the magnetic core 50, the first support layer S1 and the second support layer S2 can be formed of a thin adhesive material. ..
The first magnetic layer M1, the second magnetic layer M2, and the third magnetic layer M3 can be formed of a magnetic ribbon.

The magnetic ribbon is a magnetic material having a width of several hundred mm and a size of several tens of μm. However, the magnetic ribbon is not limited to the above size. The magnetic ribbon may contain an alloy in consideration of workability. For example, a cobalt alloy magnetic ribbon having high magnetic properties and high toughness can be used.

By forming the magnetic core 50 by laminating magnetic ribbons, the printed circuit board 200 according to the present embodiment can incorporate the magnetic core 50 formed of a plurality of layers inside.

(Third Example)
FIG. 3 is a diagram schematically showing a cross section of a printed circuit board according to a third embodiment of the present invention.
Referring to FIG. 3, the printed circuit board 300 according to the present embodiment can form the second conductor pattern 61 on one surface or the other surface of the first insulating layer 10.

Further, although not shown in the drawing, the second conductor pattern 61 formed on one surface of the first insulating layer 10 and the second conductor pattern 61 formed on the other surface of the first insulating layer 10 are connected to each other. Vias can be further formed.

(Fourth Example)
FIG. 4 is a diagram schematically showing a cross section of a printed circuit board according to a fourth embodiment of the present invention.
Referring to FIG. 4, in the printed circuit board 400 according to the present embodiment, the third insulating layer 30 can be formed on the second insulating layer 20, and the third conductor pattern 62 can be formed on the third insulating layer 30. can.
The third conductor pattern 62 may be a signal pattern, a power pattern or a ground pattern.

Compared with the printed circuit boards 100, 200, and 300 according to the first to third embodiments of the present invention, the printed circuit board 400 according to the present embodiment further forms a build-up and has various functions. It is possible to form a conductor pattern that realizes the above.

FIG. 4 shows that the third insulating layer 30 and the third conductor pattern 62 are each one, but this is merely an example. That is, unlike FIG. 4, the number of the third insulating layer 30 and the third conductor pattern 62 can be formed in two or more.

(Fifth and sixth embodiments)
FIG. 5 is a diagram schematically showing a cross section of a printed circuit board according to a fifth embodiment of the present invention.
Referring to FIG. 5, the printed circuit board 500 according to the present embodiment includes a lower insulating layer 13, a magnetic core 50, an upper insulating layer 14, and a coil pattern 40.

The printed circuit board 500 according to the present embodiment has a different coupling relationship between the lower insulating layer 13, the upper insulating layer 14, and the magnetic core 50 as compared with the printed circuit board 100 according to the first embodiment. I will explain mainly.

The lower insulating layer 13 and the upper insulating layer 14 can be formed by using a prepreg, a build-up film, or the like. That is, the lower insulating layer 13 and the upper insulating layer 14 can be formed of an insulating resin containing glass fiber, an inorganic filler, or the like.

The insulating resin may be a thermosetting insulating resin such as an epoxy resin, but is not limited thereto. That is, the insulating resin may be a photocurable insulating resin or a thermoplastic insulating resin.
The magnetic core 50 is embedded in the lower insulating layer 13 and one surface is exposed from one surface of the lower insulating layer.
The upper insulating layer 14 is formed on the upper insulating layer and the magnetic core so as to cover one surface of the lower insulating layer 13 and one surface of the magnetic core 50.

FIG. 6 is a diagram schematically showing a cross section of a printed circuit board according to a sixth embodiment of the present invention.
Here, the magnetic core 50 can have the structure of the first magnetic layer M1 laminated on one surface of the first support layer S1 and the first support layer S1.

(7th Example)
FIG. 7 is a diagram schematically showing a cross section of a printed circuit board according to a seventh embodiment of the present invention.
Referring to FIG. 7, the printed circuit board 700 according to the present embodiment includes an external insulating layer 15, an internal insulating layer 16, a magnetic core 50, and a coil pattern 40.

Comparing the printed circuit board 700 according to the present embodiment with the printed circuit boards according to the first to fifth embodiments, the insulating layers 15 and 16 and the coil pattern 40 are different, and these will be mainly described below. do.

One side of each of the external insulating layers 15 faces each other and is laminated with each other. That is, the external insulating layer 15 is formed so that one surface of the external insulating layer 15 is in contact with both surfaces of the internal insulating layer 16. As a result, each side of the external insulating layer 15 faces each other.
The coil pattern 40 is formed on the external insulating layer 15 and the internal insulating layer 16 so as to surround the magnetic core 50.

Here, the coil pattern 40 penetrates the external insulating layer 15 and the internal insulating layer 16 so that the first conductor pattern 41 formed on the other surface of the external insulating layer 15 and the first conductor pattern 41 are connected to each other. Including the connecting portion 45 to be used.

The connecting portion 45 includes a coil via 42 that penetrates the external insulating layer 15 and is connected to the first conductor pattern 41, and a metal bump 46 that penetrates the internal insulating layer 16 and connects the coil vias 42 to each other.

(Manufacturing method of printed circuit board)
Hereinafter, a method for manufacturing a printed circuit board according to an embodiment of the present invention will be described with reference to the drawings.

(First Example)
8a to 8m are views showing a method of manufacturing a printed circuit board according to the first embodiment of the present invention.
Referring to FIG. 8a, the method for manufacturing a printed circuit board according to this embodiment includes a step of preparing a first insulating layer 10.

The first insulating layer 10 is a layer formed of an insulating material such as a Cu / foil-etched substrate or a polyimide substrate, a polyester substrate, a BT resin substrate, a glass epoxy substrate, and a thermosetting polyphenylene ether substrate in a CCL substrate. There are no restrictions on the material.

Referring to FIG. 8b, the method for manufacturing a printed circuit board according to this embodiment can include a step of forming a coil pattern 40 on the first insulating layer 10.
The step of forming the coil pattern 40 can include a step of forming the coil via 42 and a step of forming the first conductor pattern 41.

In the step of forming the coil pattern 40, a usual conductor pattern forming method used in the field of printed circuit boards such as SAP (Semi-Additive Process), MSAP (Modified Semi-Adaptive Process) or Subtrackive method is used. be able to.

Referring to FIG. 8c, the method for manufacturing a printed circuit board according to this embodiment can include a step of forming a through hole C.

The through hole C can be formed by penetrating the first insulating layer 10. The first insulating layer 10 is preferably a core insulating layer having higher rigidity than other insulating layers laminated on the first insulating layer 10.

As a method for forming the through hole C, there are a method using laser drilling such as a YAG laser and a CO ₂ laser, a method using a mechanical drilling process such as a CNC drill, and the like, and there is no limitation on the forming method.

Referring to FIG. 8d, the method for manufacturing a printed circuit board according to the present embodiment can include a step of forming an adhesive layer t on one surface of a first insulating layer 10 in which a through hole C is formed.
As the adhesive layer t, an adhesive tape or an adhesive film can be used so that the magnetic core 50 firmly adheres to the through hole C.

Referring to FIG. 8e, the method for manufacturing a printed circuit board according to the present embodiment can include a step of arranging the magnetic core 50 in the through hole C.
The magnetic core 50 can be fixed in the through hole C by the adhesive layer t.

Referring to FIG. 8f, the method for manufacturing a printed circuit board according to the present embodiment can include a step of forming a second insulating layer 20 on the other surface of the first insulating layer 10.

The second insulating layer 20 is formed on the first insulating layer 10 and the magnetic core 50, and enables electrical insulation between the magnetic core 50 and the coil pattern 40. Further, the second insulating layer 20 can also be filled in the space between the through hole C formed in the first insulating layer 10 and the magnetic core 50. By filling the space between the through hole C and the magnetic core 50 with the second insulating layer 20, the magnetic core 50 can be fixed to the through hole C even after the adhesive layer t is removed.

On the other hand, FIG. 8f shows that the second insulating layer 20 is formed by using RCC (Resin Coated Copper) in which a copper foil is formed on one surface of the insulating film to be the second insulating layer 20. This is just an example. When only the insulating film is laminated on the first insulating layer 10, unlike FIG. 8f, no copper foil or metal foil is formed on the second insulating layer 20.

Referring to FIG. 8g, the method for manufacturing a printed circuit board according to this embodiment can include a step of removing the adhesive layer t.
In order to facilitate the removal of the adhesive layer, an adhesive tape or an adhesive film that can be easily peeled off can be used.

Referring to FIG. 8h, the method for manufacturing a printed circuit board according to the present embodiment can include a step of laminating a second insulating layer 20 on another surface of the first insulating layer 10.

Referring to FIG. 8i, the method for manufacturing a printed circuit board according to this embodiment can include a step of forming a via hole VH'in the second insulating layer 20.

The via hole VH'may be formed by laser drilling such as a YAG laser and / or a CO ₂ laser, or may be formed by mechanical drilling such as a CNC drill. Alternatively, when the second insulating layer 20 is a photosensitive insulating layer, the via hole VH'may be formed by a photolithography step.

Referring to FIG. 8j, the method for manufacturing a printed circuit board according to this embodiment can include a step of forming a seed layer 43.

The seed layer 43 can be formed by an electroless copper plating process. Before forming the seed layer 43, roughness may be formed on the second insulating layer 20 in order to improve the adhesive force with the second insulating layer 20.

Referring to FIGS. 8k and 8l, the method for manufacturing a printed circuit board according to this embodiment can include a step of forming a coil pattern 40.

First, as shown in FIG. 8k, a photosensitive film DF such as a patterned dry film is formed on the second insulating layer 20. The patterned dry film 45 can be formed by using a photoresist step after forming the dry film on the entire surface of the second insulating layer 20. The dried film 45 patterned here exposes a portion of the second insulating layer 20 on which the coil pattern 40 is formed.

Next, as shown in FIG. 8l, after forming the coil pattern 40, the patterned dry film DF is removed.

The coil pattern 40 can be formed by electrolytic plating. In this case, the above-mentioned patterned dry film becomes a plating resist. During electrolytic plating, the seed layer described above functions as a feeding layer.

Then, referring to FIG. 8 m, the method for manufacturing a printed circuit board according to this embodiment can include a step of forming a solder resist 70. The solder resist 70 is formed with an opening that exposes a part of the coil pattern 40.

By such a method for manufacturing a printed circuit board according to the present embodiment, the printed circuit board according to the first embodiment of the present invention described above can be manufactured.

(Manufacturing method of magnetic core)
Hereinafter, a method for manufacturing a magnetic core applied to the method for manufacturing a printed circuit board according to this embodiment will be described.
9a to 9e are diagrams showing a method of manufacturing a magnetic core according to an embodiment.

Referring to FIG. 9a, the method for manufacturing the magnetic core 50 according to the embodiment can include a step of preparing the first support layer S1.

Referring to FIG. 9b, the method for manufacturing the magnetic core 50 according to the embodiment can include a step of forming the first magnetic layer M1 on one surface of the first support layer S1.

Referring to FIG. 9c, the method for manufacturing the magnetic core 50 according to the embodiment can include a step of forming the second magnetic layer M2 on the other surface of the first support layer S1.

Referring to FIGS. 9d and 9e, in the method for manufacturing the magnetic core 50 according to the embodiment, the first support layer S1 in which the first magnetic layer M1 and the second magnetic layer M2 are laminated on both sides has a constant size. Can include a step of cutting into.

10a to 10c are diagrams showing a method for manufacturing a magnetic core according to another embodiment.
Referring to FIG. 10a, as a method for manufacturing a magnetic core according to another embodiment, a first magnetic layer M1, a first support layer S1, a second magnetic layer M2, a second support layer S2, and a third magnetic layer M3 are prepared. Can include stages of

Next, referring to FIGS. 10b and 10c, the method for manufacturing a magnetic core according to another embodiment is as follows: first magnetic layer M1, first support layer S1, second magnetic layer M2, second support layer S2, and first. The step of sequentially laminating the three magnetic layers M3 and then cutting them into a predetermined size can be included.

However, when laminating the above magnetic layer and support layer, it is not always necessary to sequentially stack them.
At the stage of cutting to a predetermined size, the predetermined size is a size that can be inserted into the through hole C, and may be determined in consideration of the performance of the printed circuit board and the like.

Therefore, since the magnetic core according to the embodiment of the present invention is used by cutting it to a required size after the magnetic layer is formed on the support layer, it is not necessary to remove the magnetic layer by etching.

(2nd example and modification)
11a to 11o are diagrams showing a manufacturing method, a modification, and the like of the printed circuit board according to the second embodiment of the present invention.
First, the carrier 90 is prepared as shown in FIG. 11a.

The carrier 90 can have a structure in which the first metal foil 92 and the second metal foil 93 are formed on both sides of the support portion 91, respectively. The support 91 may be a prepreg, but is not limited thereto. The first metal foil 92 and the second metal foil 93 may be formed of the same material as each other, or may be formed of different materials from each other. As an example, the first metal leaf 92 and the second metal leaf 93 can all be made of copper.
The same process can be performed on both sides of the carrier 90 to manufacture two printed circuit boards at the same time, but the present invention is not limited to this.

Next, as shown in FIG. 11b, the first conductor pattern 41 is formed on the second metal foil 93.
In the case of this embodiment, the first conductor pattern 41 includes a dummy pattern D. The dummy pattern D is removed in a subsequent step, and the magnetic core 50 can be arranged or formed at the position where the dummy pattern D was.

The first conductor pattern 41 can be formed by electrolytic plating using the above-mentioned second metal foil 93 as a feeding layer. However, this is merely an example, and the first conductor pattern 41 can also be formed by the subtrackive method.

Next, as shown in FIG. 11c, the lower insulating layer 13 is formed. The lower insulating layer 13 can be formed using RCC, but is not limited thereto. When the lower insulating layer 13 is formed on the carrier 90 using only the insulating film, unlike FIG. 11c, no metal foil is formed on the lower insulating layer 13.

Next, as shown in FIG. 11d, the coil via 42 and the first conductor pattern 41 are formed on the lower insulating layer 13. The coil via and the first conductor pattern 41 can be formed by forming a via hole in the lower insulating layer 13 and then forming a seed layer and electrolytic plating.

Next, as shown in FIG. 11e, the lower insulating layer 13 is separated from the carrier 90. At this time, separation can occur at the interface between the first metal leaf 92 and the second metal leaf 93 of the carrier 90. As a result, the second metal foil 93 is in a state of being attached to the lower insulating layer 13. In this case, the second metal leaf 93 adhering to the lower insulating layer 13 can be removed from the lower insulating layer 13 by flash etching or the like.

Next, as shown in FIGS. 11f and 11g, a resist 80 is formed on both surfaces of the lower insulating layer 13. The resist 80 can be formed by laminating a photosensitive film such as a dry film on both surfaces of the lower insulating layer 13. The resist 80 is formed with an opening for exposing the dummy pattern D embedded in the lower insulating layer 13 by the photolithography process.

Next, as shown in FIG. 11h, the dummy pattern D is removed. When the dummy pattern D is made of copper, the dummy pattern D can be removed by the copper etching solution flowing in from the opening of the resist 80. At this stage, the resist 80 functions as an etching resist.

Next, as shown in FIG. 11i, the magnetic core 50 is formed. The magnetic core 50 can be formed by a thin film process such as sputtering. With the resist 80, the magnetic core 50 can be formed only at the position where the dummy pattern D is removed in the lower insulating layer 13.

Next, as shown in FIG. 11j, the resist 80 is removed. The resist 80 can be removed from the lower insulating layer 13 using a stripping solution.

Next, as shown in FIG. 11k, the upper insulating layer 14 is formed on the lower insulating layer 13. RCC can be used when forming the upper insulating layer 14, but is not limited thereto.

Next, as shown in FIGS. 11l and 11m, the coil pattern 40 is formed on the upper insulating layer 14, and then the solder resist 70 is formed on the upper insulating layer 14 and the lower insulating layer 13.
The printed circuit board according to the fifth embodiment of the present invention can be manufactured by the method for manufacturing the printed circuit board according to the present embodiment.

11n and 11o relate to a modification of this embodiment, and specifically, show other forms of the magnetic core 50, respectively, corresponding to FIG. 11j.

(Third Example)
12a to 12o are diagrams showing a method for manufacturing a printed circuit board according to a third embodiment of the present invention.

In the case of this embodiment, unlike the method for manufacturing a printed circuit board according to the second embodiment described above, different unit substrates are formed on both sides of the carrier 90. Further, in the case of this embodiment, unlike the method for manufacturing the printed circuit board according to the first and second embodiments described above, the batch laminating method is used instead of the sequential laminating method.

In this embodiment, a stage of forming a precursor of a first unit substrate and a precursor of a second unit substrate using a carrier, a stage of forming a first unit substrate and a second unit substrate, and a stage of forming a first unit substrate are used. It can be roughly divided into the stage of batch stacking the second unit substrate and the second unit substrate.

(Step of forming 1st unit substrate precursor and 2nd unit substrate precursor)
First, the carrier 90 is prepared as shown in FIG. 12a.

After that, as shown in FIG. 12b, the first conductor pattern 41 of the first unit substrate is formed on the upper surface of the carrier 90, and the first conductor pattern 41 of the second unit substrate is formed on the lower surface of the carrier 90. Here, the first conductor pattern 41 on the lower surface of the carrier 90 includes the dummy pattern D.

Next, as shown in FIG. 12c, external insulating layers 15 are formed on both sides of the carrier 90, respectively. The external insulating layer 15 can be formed by RCC as shown in FIG. 12c. However, when the external insulating layer 15 is formed only of the insulating film, unlike FIG. 12c, no metal foil is formed on the upper surface of the external insulating layer 15.

Next, as shown in FIG. 12d, the first conductor pattern and the coil via 42 are formed on the external insulating layer 15.
Next, as shown in FIG. 12e, the upper external insulating layer 15 and the lower external insulating layer 15 are separated from the carrier 90. The upper external insulating layer 15 is a precursor of the first unit substrate, and the lower external insulating layer 15 is a precursor of the second unit substrate.

(Stage of forming the 1st unit substrate and the 2nd unit substrate)
A method for manufacturing the first unit substrate will be described.
First, as shown in FIG. 12f, the internal insulating layer 16 is formed on the precursor of the first unit substrate located at the upper part of FIG. 12e. Specifically, the internal insulating layer 16 is formed on one surface of the external insulating layer 15 of the first unit substrate.
The internal insulating layer 16 may be a photosensitive insulating layer, but is not limited thereto.

Next, as shown in FIG. 12g, an opening for forming the metal bump 46 is formed in the internal insulating layer 16. The openings can be formed by laser drilling or mechanical drilling. When the internal insulating layer 16 is a photosensitive insulating layer, the openings can be formed by applying a photolithography step to the internal insulating layer 16.

Next, as shown in FIG. 12h, a metal bump 46 and a connecting layer 47 are formed in the opening. The metal bump 46 can be formed by electrolytic plating. The connection layer 47 can be formed of a material having a melting point lower than the melting point of the metal bump 46. As an example, if the metal bump 46 is made of copper, the connecting layer 47 can be made of a tin-containing solder. The connecting layer can be formed by electrolytic plating or a paste coating method.

Hereinafter, a method for manufacturing the second unit substrate will be described.
First, as shown in FIGS. 12i and 12j, resist 80 is formed on both sides of the precursor of the second unit substrate located at the lower part of FIG. 12e. The resist 80 can be formed by laminating a photosensitive film such as a dry film on both surfaces of the external insulating layer 15. The resist 80 is formed with an opening for exposing the dummy pattern D embedded in the external insulating layer 15 by the photolithography process.

Next, as shown in FIG. 12k, the dummy pattern D is removed. When the dummy pattern D is made of copper, the dummy pattern D can be removed by the copper etching solution flowing in from the opening of the resist 80. At this stage, the resist 80 functions as an etching resist.

Next, as shown in FIG. 12l, the magnetic core 50 is formed. The magnetic core 50 can be formed by a thin film process such as sputtering. With the resist 80, the magnetic core 50 can be formed only at the position where the dummy pattern D is removed in the external insulating layer 15.
Next, as shown in FIG. 12m, the resist 80 is removed. The resist 80 can be removed from the external insulating layer 15 using a stripping solution.

(Step of batch stacking the 1st unit substrate and the 2nd unit substrate)
As shown in FIG. 12n, the first unit substrate and the second unit substrate are aligned with each other. At this time, the first unit substrate and the second unit substrate can be aligned by using the reference holes or the like formed in each of them.

After that, the first unit substrate and the second unit substrate are pressurized and heated. At this time, batch lamination can be performed at a temperature higher than the melting point of the connection layer 47.
As described above, the printed circuit board according to the seventh embodiment of the present invention can be manufactured by the method for manufacturing the printed circuit board according to the present embodiment.

Although one embodiment of the present invention has been described above, if the person has ordinary knowledge in the technical field, the addition of components can be performed within the range not deviating from the idea of the present invention described in the claims. The present invention can be variously modified and changed by modification, deletion, addition, etc., and it can be said that this is also included in the scope of the rights of the present invention.

10 1st insulating layer 13 Lower insulating layer 14 Upper insulating layer 15 External insulating layer 16 Internal insulating layer 20 2nd insulating layer 30 3rd insulating layer 40 Coil pattern 41 1st conductor pattern 42 Coil via 43 Seed layer 45 Connection part 46 Metal bump 47 Connection layer 50 Magnetic core 61 2nd conductor pattern 62 3rd conductor pattern 70 Solder resist 80 Resist 90 Carrier 91 Support part 92 1st metal foil 93 2nd metal foil C Through hole t Adhesive layer D Dummy pattern DF Dry film

Claims (10)

The first insulating layer on which the through hole was formed and
A second insulating layer that covers both sides of the first insulating layer and has a lower rigidity than the first insulating layer.
The magnetic core arranged in the through hole and
A coil pattern formed on one surface and the other surface of the second insulating layer so as to wind around the magnetic core.
The magnetic core includes a first support layer arranged so as to surround the first insulating layer and a first magnetic layer formed on one surface of the first support layer so as to surround the first insulating layer. Printed circuit board. The coil pattern is
To wind around the magnetic core at least once
A first conductor pattern formed on one surface and the other surface of the second insulating layer by separating them from each other.
In order to electrically connect the first conductor pattern formed on one surface of the second insulating layer and the first conductor pattern formed on the other surface of the second insulating layer, the first insulating layer and the first insulating layer are connected. 2. The printed circuit board according to claim 1, further comprising a coil via penetrating the insulating layer. The magnetic core is
The printed circuit board according to claim 1 or 2, further comprising a second magnetic layer laminated on the other surface of the first support layer so as to surround the first insulating layer. The magnetic core is
A second support layer formed on the second magnetic layer so as to surround the first insulating layer, and a third magnetic layer formed on the second support layer so as to surround the first insulating layer. The printed circuit board according to claim 3, further comprising. The printed circuit board according to any one of claims 1 to 4, wherein the first magnetic layer is formed of a magnetic ribbon. The printed circuit board according to any one of claims 1 to 5, further comprising a second conductor pattern formed on one surface or the other surface of the first insulating layer. The printed circuit board according to claim 6, further comprising a via for penetrating the first insulating layer and electrically connecting the second conductor pattern formed on one surface and the other surface of the first insulating layer. The printed circuit board according to claim 6 or 7, further comprising a third insulating layer formed on one surface of the second insulating layer. The printed circuit board according to claim 8, further comprising a third conductor pattern formed on the third insulating layer. The printed circuit board according to any one of claims 1 to 9, wherein the magnetic core and the first insulating layer are separated from each other.

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