JP2019041017A - Coil parts - Google Patents

Abstract

It is possible to control characteristics with high accuracy.
A coil component 1 is laminated on a first magnetic resin layer 21, a first insulating resin layer 17a laminated on the first magnetic resin layer 21, and a first insulating resin layer 17a. A coil unit 20 including the coil 11 and a second insulating resin layer 17b covering the coil 11, and a second magnetic resin layer 22 laminated on the first insulating resin layer 17a and the coil unit 20; The first insulating resin layer 17a has a through-hole 171 in a region sandwiched between the first magnetic resin layer 21 and the second magnetic resin layer 22 along the stacking direction. The magnetic resin of the two magnetic resin layer 22 is filled in the through hole 171.
[Selection] Figure 3

Description

  The present invention relates to a coil component.

  In order to realize a desired inductance in an inductance element such as a transformer mounted on a switching power supply or the like, it has been studied to change the size of a gap between butt ends of cores (for example, Patent Document 1). , 2)

JP 2010-212271 A JP-A-11-340064

  However, it is difficult to apply the inductance control by the gap between the cores described in Patent Documents 1 and 2 or the like to a coil component constituted by a planar conductor and a magnetic member. A coil component using a planar conductor has a lower height than a conventional inductance element, and it is difficult to accurately adjust the gap. Therefore, a technique for adjusting the inductance with higher accuracy is required.

  The present invention has been made in view of the above, and an object thereof is to provide a coil component capable of controlling characteristics with high accuracy.

  In order to achieve the above object, a coil component according to an aspect of the present invention includes a first magnetic resin layer, a first insulating resin layer laminated on the first magnetic resin layer, and the first insulating resin. A coil part including a coil layer laminated on the layer; a second insulating resin layer covering the coil layer; and a second magnetic resin laminated on the first insulating resin layer and the coil part. And the first insulating resin layer has a through hole in a region sandwiched between the first magnetic resin layer and the second magnetic resin layer along the stacking direction, and the first magnetic resin The through hole is filled with the magnetic resin of the layer or the second magnetic resin layer.

  According to the coil component described above, in the first insulating resin layer, since the through hole is provided in the region sandwiched between the first magnetic resin layer and the second magnetic resin layer, the size and arrangement of the through hole Etc. can be used to control the characteristics of the coil component. Therefore, the characteristics of the coil component can be controlled with high accuracy.

  Here, the first magnetic resin layer and the second magnetic resin layer may be formed of the same material.

  As described above, when the first magnetic resin layer and the second magnetic resin layer are made of the same material, the first magnetic resin layer and the second magnetic resin layer are integrated by the magnetic resin filled in the through hole. The Therefore, peeling of the magnetic resin layer and the like are prevented, and damage as a coil component is prevented.

  Moreover, the said through-hole can be made into the aspect larger than the average particle diameter of the filler of the said magnetic resin with which the said through-hole is filled.

  As described above, by setting the through holes larger than the average particle diameter of the filler of the magnetic resin, the filler can easily enter the through holes, and the filler is preferably dispersed in the magnetic resin.

  ADVANTAGE OF THE INVENTION According to this invention, the coil component which can perform characteristic control with high precision is provided.

It is a top view of the coil components which concern on this embodiment. It is a disassembled perspective view of the one part structural member of coil components. It is sectional drawing which showed the internal structure of the coil components typically. It is a figure explaining the manufacturing method of coil components. It is a figure explaining the manufacturing method of coil components. It is a figure explaining the 1st insulating resin layer of the coil components used for evaluation. It is a figure which shows the characteristic evaluation result of a coil component. It is a figure explaining the 1st insulating resin layer of the coil components used for evaluation. It is a figure which shows the characteristic evaluation result of a coil component.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  A schematic configuration of a coil component according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view of a coil component according to the present embodiment, FIG. 2 is an exploded perspective view of a part of the component of the coil component, and FIG. 3 is a cross-sectional view schematically showing the internal structure. is there. In FIG. 2, the magnetic resin layer included in the coil component is omitted.

  As shown in FIGS. 1 to 3, the coil component 1 includes an element body 10 (magnetic element body) in which a coil 11 described later is provided, and an insulating layer 30 provided on the main surface 10 a of the element body 10. And. On the insulating layer 30, terminal electrodes 16A and 16B are provided. The coil component 1 has a substantially rectangular shape with a short side of about 0.2 mm to 0.7 mm and a long side of about 0.8 mm to 1.2 mm in a plan view, and a thickness of about 30 μm to 500 μm. . The shape in plan view is not particularly limited.

  In the present specification, the “stacking direction” is a direction in which the element body 10 and the insulating layer 30 are sequentially overlapped. In the following description, the terminal electrodes 16A and 16B side may be described as “upper” along the stacking direction, and the element body 10 side may be described as “lower” along the stacking direction.

  The element body 10 has a rectangular parallelepiped outer shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape in which corners and ridge lines are chamfered and a rectangular parallelepiped shape in which corners and ridge lines are rounded. The main surface 10a of the element body 10 has a rectangular shape having a long side and a short side. The rectangular shape includes a rectangle with rounded corners.

  Terminal electrodes 16 </ b> A and 16 </ b> B are provided on the main surface 10 a of the element body 10 via an insulating layer 30. The terminal electrode 16A is provided on one short side of the main surface 10a, and the terminal electrode 16B is provided on the other short side of the main surface 10a. The terminal electrodes 16A and 16B are separated from each other in the direction along the long side of the main surface 10a.

  The element body 10 is made of, for example, a magnetic material. Specifically, the element body 10 is disposed inside the first magnetic resin layer 21, the second magnetic resin layer 22, and the second magnetic resin layer 22 between the first magnetic resin layer 22 and the second magnetic resin layer 22. The coil 11, the covering portion 17, and the lead conductors 15A and 15B are provided. The covering portion 17 includes a first insulating resin layer 17a and a second insulating resin layer 17b. A coil portion 20 is formed by the coil 11 and the second insulating resin layer 17b.

  The coil 11 is made of a conductive metal material such as copper (Cu), for example, and its axis extends along a direction orthogonal to the main surface 10a. The coil 11 has two coil conductor layers, and a first coil layer 12 and a second coil layer 13 serving as coil conductor layers, and a connecting portion that connects the first coil layer 12 and the second coil layer 13. 14 and lead conductors 15A and 15B.

  The first coil layer 12 and the second coil layer 13 are arranged in a direction perpendicular to the main surface 10 a of the element body 10 (the axial center direction of the coil portion 20), and the second coil layer 13 is the first coil layer 12. It is located on the main surface 10a side (the upper side in the figure). The first coil layer 12 and the second coil layer 13 have the same winding direction. The connecting portion 14 is interposed between the first coil layer 12 and the second coil layer 13 to connect the inner end portion of the first coil layer 12 and the inner end portion of the second coil layer 13. Yes. In addition, although the case where the 1st coil layer 12 and the 2nd coil layer 13 are each a coil of multiple turns is demonstrated, the number of coil layers and the number of turns in each coil layer are not limited.

  In the coil 11, the first coil layer 12 and the second coil layer 13 each have a thickness of about 30 μm to 80 μm, and the overall thickness is about 70 μm to 180 μm.

  The coil 11 is covered with a covering portion 17. The coating | coated part 17 has insulation and is comprised with insulating resin. Examples of the insulating resin used for the covering portion 17 include polyimide and polyethylene terephthalate.

  The covering portion 17 integrally covers the first coil layer 12 and the second coil layer 13 in the element body 10, and the covering portion 17 is sandwiched between adjacent conductor layers. The covering portion 17 includes a first insulating resin layer 17a provided below the first coil layer 12 (on the side opposite to the main surface 10a) and an upper side (main surface) of the first insulating resin layer 17a. 10a side) and a second insulating resin layer 17b laminated together with the first coil layer 12 and the second coil layer.

  The first insulating resin layer 17a is located below the first coil layer 12 (on the opposite side to the main surface 10a), and is formed in substantially the same shape as the main surface 10a of the element body 10 in plan view. The first insulating resin layer 17 a has a through hole 171 smaller than the above opening in a region corresponding to the opening provided inside the first coil layer 12 and the second coil layer 13. FIG. 3 shows an example in which two through holes 171 are provided, but the number and size of the through holes 171 can be changed as appropriate. This point will be described later.

  In addition, the second insulating resin layer 17b fills the periphery and the space between the first coil layer 12 and the second coil layer 13 in the same layer. The second insulating resin layer 17b is provided so as to cover between the first coil layer 12 and the second coil layer 13 and above the second coil layer 13 (on the main surface 10a side). Further, in the second insulating resin layer 17b, an area inside the inner shape of the first coil layer 12 and the second coil layer 13 (an opening is formed by the first coil layer 12 and the second coil layer 13). An opening is formed in the region. Thus, the coil 11 is in a state of being covered with the second insulating resin layer 17b. In the present embodiment, the second insulating resin layer 17b covers only the periphery of the first coil layer 12 and the upper part thereof, and the main surface of the coil layer on the first insulating resin layer 17a side is exposed. Even so, the coil 11 is covered with the second insulating resin layer 17b.

  The second insulating resin layer 17b may also be provided below the first coil layer 12 (on the side opposite to the main surface 10a).

  In a plan view, the outer shape of the second insulating resin layer 17 b corresponds to the outer shapes of the first coil layer 12 and the second coil layer 13. Therefore, in plan view, the first insulating resin layer 17a having a shape corresponding to the main surface 10a of the element body 10 is larger than the second insulating resin layer 17b. Further, the opening inside the second insulating resin layer 17b corresponds to the opening of the first coil layer 12 and the second coil layer 13, but the through hole 171 provided in the first insulating resin layer 17a It is smaller than the opening of the second insulating resin layer 17b. Therefore, in a plan view, the first insulating resin layer 17a can be confirmed in the opening inside the second insulating resin layer 17b.

  The thickness of the 1st insulating resin layer 17a can be 3 micrometers-30 micrometers, for example. The thickness of the second insulating resin layer 17b is set based on the thickness of the coil 11 and the like, and is about 3 μm to 30 μm, for example.

  The first magnetic resin layer 21 and the second magnetic resin layer 22 are provided with the first insulating resin layer 17a interposed therebetween. Specifically, the coil portion 20 including the second insulating resin layer 17b and the coil 11 is laminated on the first insulating resin layer 17a, but in a region different from the region where the coil portion 20 is laminated. The first magnetic resin layer 21 and the second magnetic resin layer 22 are sandwiched. The 1st magnetic resin layer 21 is laminated | stacked with respect to the main surface on the opposite side to the main surface by which the 1st coil layer 12 is formed among the 1st insulating resin layers 17a (namely, downward). The second magnetic resin layer 22 is laminated on the main surface of the first insulating resin layer 17a on the side where the first coil layer 12 is formed (that is, above). The second magnetic resin layer 22 is formed on the first insulating resin layer 17 a with the second insulating resin layer 17 b included in the coil 11 and the covering portion 17 inside.

  The through hole 171 of the first insulating resin layer 17 a is formed in a region sandwiched between the first magnetic resin layer 21 and the second magnetic resin layer 22.

  The first magnetic resin layer 21 and the second magnetic resin layer 22 are each a mixture of magnetic powder and binder resin. The constituent material of the magnetic powder is, for example, iron, carbonyl iron, silicon, cobalt, chromium, nickel, or boron, and is dispersed in the layer as a magnetic filler. Although the average particle diameter of a filler is not specifically limited, For example, it can be set as about 1 micrometer-30 micrometers. The constituent material of the binder resin is, for example, an epoxy resin. In each of the first magnetic resin layer 21 and the second magnetic resin layer 22, for example, 90% or more of the whole may be composed of magnetic powder. The first magnetic resin layer 21 and the second magnetic resin layer 22 may be made of the same material, but may be made of different materials.

  Note that either the first magnetic resin layer 21 or the second magnetic resin layer 22 is also introduced into the through hole 171 provided in the first insulating resin layer 17a. Then, the first magnetic resin layer 21 and the second magnetic resin layer 22 are integrated by the insulating resin in the through hole 171.

  The lead conductors 15 </ b> A and 15 </ b> B constitute end portions of the coil 11, respectively. The lead conductor 15A extends from the outer end E1 of the first coil layer 12 in a direction orthogonal to the main surface 10a. The lead conductor 15B extends from the outer end E2 of the second coil layer 13 along a direction orthogonal to the main surface 10a. The lead conductors 15 </ b> A and 15 </ b> B both extend upward through the covering portion 17 and the second magnetic resin layer 22.

  End portions of the lead conductors 15A and 15B, that is, both end portions of the coil 11 are connected to terminal electrodes 16A and 16B provided on the main surface 10a of the element body 10 of the coil component 1, respectively. The terminal electrodes 16A and 16B are connected to the ends of the internal coil 11, respectively. The terminal electrodes 16A and 16B are both film-like and have a substantially square shape in plan view. Further, the terminal electrodes 16A and 16B are made of a conductive material such as Cu, for example. The terminal electrodes 16A and 16B may have a single layer structure or a multiple layer structure.

  Next, the manufacturing method of the coil component 1 is demonstrated, referring FIG.4 and FIG.5. First, as shown in FIG. 4A, the coil 11, the covering portion 17 (the first insulating resin layer 17a and the second insulating resin layer 17b), and the lead conductors 15A and 15B are formed on the substrate 50. . A well-known method can be utilized for the manufacturing method of the 1st insulating resin layer 17a, the coil 11, and the 2nd insulating resin layer 17b. The following describes an example. First, an insulating resin layer between adjacent first coil layers 12 is formed on the first insulating resin layer 17a, and a base metal layer is provided in a region to be the first coil layer 12, and the first coil layer is formed by plating. 12 is formed. Then, while providing the insulating resin layer between the 1st coil layer 12 and the 2nd coil layer 13, the connection part 14 and the extraction conductor 15A are formed. By repeating the same process, the second coil layer 13 and the insulating resin layer thereabove are formed, and the coil 11, the covering portion 17 (the first insulating resin layer 17a and the second insulating resin layer 17b), and Lead conductors 15A and 15B are formed. In forming the lead conductors 15A and 15B, a molding insulating material is provided around them, but these are removed after the lead conductors 15A and 15B are formed.

  Next, as shown in FIG. 4B, a second magnetic resin layer 22 is formed around the covering portion 17 and the lead conductors 15A and 15B. The second magnetic resin layer 22 is formed, for example, by applying and curing a material.

  Next, as shown in FIG. 5A, the base material 50 is removed to expose the first insulating resin layer 17a. Thereafter, a through hole 171 is formed in the first insulating resin layer 17a from the lower surface side (the exposed surface side of the first insulating resin layer 17a).

  Thereafter, as shown in FIG. 5B, the first magnetic resin layer 21 is laminated on the lower surface side of the first insulating resin layer 17a. At this time, the magnetic resin of the first magnetic resin layer 21 is also filled in the through hole 171. Thereby, the element body 10 is formed. Then, the coil component 1 shown in FIGS. 1-3 is obtained by forming the insulating layer 30 and terminal electrode 16A, 16B in the main surface 10a of the element | base_body 10. As shown in FIG.

  The through hole 171 may be formed before the second magnetic resin layer 22 is formed, for example, instead of the timing shown in FIG. In this case, the through hole 171 is filled with the magnetic resin of the second magnetic resin layer 22. The through hole 171 may be filled with any magnetic resin of the first magnetic resin layer 21 and the second magnetic resin layer 22.

  In the coil component 1 according to the present embodiment, the through-hole 171 is provided in the first insulating resin layer 17a, so that the inductance (L value) of the coil component 1 can be adjusted by the through-hole 171. It is characterized by.

  In addition to the configuration of the coil layer such as the number of turns and the width (the size of the cross-sectional area), the elements that control the characteristics of the electronic component having a coil such as the coil component 1 include a magnetic resin layer around the coil portion. The magnitude of magnetic flux in known magnetic materials is known. Therefore, conventionally, in coil components including a core material as a magnetic material, characteristics (inductance (L) and saturation magnetic flux density (Bs)) are controlled by adjusting a gap between the cores. Yes. However, the control of the gap between the cores can be easily performed, but the same control is difficult in a thin-film electronic component such as the coil component 1 according to the present embodiment. In the case of the coil component 1, by controlling the thickness of the first insulating resin layer 17 a, the same control as the gap between the cores in the conventional coil component can be realized, but the first insulating resin layer 17 a There was a problem that it was difficult to accurately control the thickness.

  On the other hand, in the coil component 1 according to the present embodiment, the inductance and the saturation magnetic flux density can be controlled by adjusting the size and arrangement of the through holes 171 in the same manner as the control by the inter-core gap. Therefore, the characteristics of the thin-film coil component 1 can be suitably controlled.

  The through hole 171 of the first insulating resin layer 17a is a region sandwiched between the first magnetic resin layer 21 and the second magnetic resin layer 22 (the first insulating resin layer 17a is the first magnetic resin on one main surface). A region in contact with the layer 21 and in contact with the second magnetic resin layer 22 on the other main surface). The region sandwiched between the first magnetic resin layer 21 and the second magnetic resin layer 22 is inside the region where the coil part 20 is laminated in the first insulating resin layer 17a (opening around the axis of the coil 11). ) And the outside of the region where the coil part 20 is laminated. The region sandwiched between the first magnetic resin layer 21 and the second magnetic resin layer 22 is a region where a magnetic path is formed by the magnetic resin layer. By providing the through hole 171 in the region, the magnetic flux can be controlled, and the electrical characteristics of the coil component 1 can be controlled.

  Here, control of the characteristics of the coil component 1 by changing the size and arrangement of the through holes 171 will be described with reference to FIGS.

  First, the results of evaluating the relationship between the aperture ratio of the through hole 171, the inductance (L), and the rated current (Isat) will be shown with reference to FIGS. 6 and 7. Here, three types of coil components 1 having different opening ratios of the first insulating resin layer 17a through the through holes 171 were prepared. 6A to 6C are diagrams for explaining the arrangement of the through holes 171 in the three types of coil components. FIG. 6A shows a state in which the through hole 171 is not provided in the first insulating resin layer 17a. In FIG. 6 (and FIG. 8 described later), a region R1 where the second insulating resin layer 17b is laminated and a region R2 where the second insulating resin layer 17b is not laminated are distinguished. The region R1 where the second insulating resin layer 17b is laminated is a region where the coil 11 is provided above, so that the region R1 is not sandwiched between the first magnetic resin layer 21 and the second magnetic resin layer 22. Therefore, the through hole 171 is not provided in the region R1. Therefore, the “opening ratio” here indicates the ratio of the area in which the through-hole 171 is provided to the area of the region R2 where the second insulating resin layer 17b is not stacked above.

  FIG. 6B shows a state where the aperture ratio is 23%. A through hole 171 provided in the first insulating resin layer 17a shown in FIG. 6B is circular and is provided both inside and outside the coil 11 (see FIG. 3 and the like).

  FIG. 6C shows a state where the aperture ratio is 37%. The through hole 171 provided in the first insulating resin layer 17a shown in FIG. 6C has the same circular shape as the through hole 171 shown in FIG. 6B, and is inside the coil 11 (see FIG. 3 etc.). And on the outside.

  FIG. 7 shows the result of evaluating the electrical characteristics of the coil component having the three types of first insulating resin layers 17a by simulation. FIG. 7 shows the result of calculating the inductance and the rated current when the current of the same condition is passed with the thickness of the first insulating resin layer 17a being common. As shown in FIG. 7, it was confirmed that increasing the aperture ratio increases the inductance (L). On the other hand, it was confirmed that the rated current (Isat) decreases as the aperture ratio increases. Therefore, it was confirmed that the characteristics of the coil component can be controlled by changing the aperture ratio.

  Next, referring to FIG. 8 and FIG. 9, the result of evaluating the relationship between the inductance (L) and the rated current (Isat) when the arrangement of the through holes 171 is changed while the aperture ratio of the through holes 171 is constant. Indicates. Here, three types of coil components 1 were prepared in which the opening ratio of the first insulating resin layer 17a by the through holes 171 was 37% and the shapes of the through holes 171 were different from each other. One is provided with a plurality of circular through-holes 171 as shown in FIG. FIG. 8A shows a state where an annular through hole is provided on the inner peripheral side of the region R1 where the second insulating resin layer 17b is laminated in the first insulating resin layer 17a. . In FIG. 8B, in the first insulating resin layer 17a, annular through holes are provided on both the inner and outer peripheral sides of the region R1 where the second insulating resin layer 17b is laminated. It shows the state. By adjusting the width of the annular through hole 171, the aperture ratios of the through holes 171 were all adjusted to 37%.

  FIG. 9 shows the results of evaluating the electrical characteristics of the coil component having the three types of first insulating resin layers 17a by simulation. In FIG. 9, similarly to FIG. 7, the results of calculating the inductance and the rated current when the current of the same condition is flowed with the thickness of the first insulating resin layer 17 a being common are shown. “Equal hole” shown in FIG. 9 indicates a result relating to the first insulating resin layer 17a of FIG. 6C in which circular through holes 171 are arranged in a dispersed manner. 9 indicates the result of the first insulating resin layer 17a in FIG. 8A, and “uniform band” indicates the first insulating resin in FIG. 8B. The result concerning the layer 17a is shown. As shown in FIG. 9, it was confirmed that the inductance (L) and the rated current (Isat) change according to the arrangement of the aperture ratio. Therefore, it was confirmed that the characteristics of the coil component can be controlled by changing the aperture ratio and the shape and arrangement of the through holes 171.

  As described above, in the first insulating resin layer 17a, by controlling the arrangement, size (opening ratio), and the like of the through holes 171 penetrating the first magnetic resin layer 21 side and the second magnetic resin layer 22 side. It was confirmed that the electrical characteristics of the coil component 1 can be controlled. Therefore, the characteristics of the coil component 1 can be suitably controlled by designing the arrangement, size (opening ratio), and the like of the through holes 171 according to the electrical characteristics required for the coil component 1.

  Moreover, when the 1st magnetic resin layer 21 and the 2nd magnetic resin layer 22 in the coil component 1 are the same materials, damage, such as peeling, can be prevented compared with the conventional coil component. Conventional thin-film coil components often employ a configuration in which a coil portion covered with a covering portion is disposed on a magnetic substrate such as a ferrite substrate and the periphery is covered with a magnetic material. In this case, it is conceivable that peeling occurs between the magnetic resin layer and the ferrite substrate due to the difference in thermal expansion coefficient. On the other hand, when both are integrated through the through-hole 171 of the 1st insulating resin layer 17a like the coil component 1, the 1st magnetic resin layer 21 and the 2nd magnetic resin layer 22 are the same. When it is a material, the adhesion is increased. Therefore, the damage etc. of the coil component 1 are prevented.

  The size (inner diameter) of the through-hole 171 is not particularly limited, but the filler contained in the magnetic resin filled in the through-hole 171 among the magnetic resins of the first magnetic resin layer 21 and the second magnetic resin layer 22. It is preferable that it is larger than the diameter. With such a configuration, the filler of the magnetic powder easily enters the through hole 171 and the filler is preferably dispersed.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to said embodiment, A various change can be made. For example, in the above embodiment, the number of coil layers included in the coil 11 is not particularly limited and can be arbitrarily changed. Further, the arrangement and shape of the coupling layer, the lead conductor, and the like can be appropriately changed according to the number and shape of the coil layers.

  Moreover, although the said embodiment demonstrated the case where the shape of the through-hole 171 was an annular | circular shape or circular shape, about the shape of the through-hole 171, etc., it can change suitably.

  DESCRIPTION OF SYMBOLS 1 ... Coil component, 10 ... Element body, 11 ... Coil, 12 ... 1st coil layer, 13 ... 2nd coil layer, 14 ... Connection part, 15A, 15B ... Lead conductor, 16A, 16B ... Terminal electrode, 17 ... Covering Part, 17a ... first insulating resin layer, 17b ... second insulating resin layer, 20 ... coil part, 21 ... first magnetic resin layer, 22 ... second magnetic resin layer, 171 ... through hole.

Claims (3)

A first magnetic resin layer;
A first insulating resin layer laminated on the first magnetic resin layer;
A coil portion including a coil layer laminated on the first insulating resin layer, and a second insulating resin layer covering the coil layer;
A second magnetic resin layer laminated on the first insulating resin layer and the coil portion;
Have
The first insulating resin layer has a through hole in a region sandwiched between the first magnetic resin layer and the second magnetic resin layer along the stacking direction,
The coil component, wherein the through hole is filled with the magnetic resin of the first magnetic resin layer or the second magnetic resin layer.   The coil component according to claim 1, wherein the first magnetic resin layer and the second magnetic resin layer are made of the same material.   The coil component according to claim 1 or 2, wherein the through hole is larger than an average particle diameter of the filler of the magnetic resin filled in the through hole.

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