Coil component

Abstract

The present invention improves the strength of a terminal part in a coil component having a planar coil pattern that can be electrically accessed from the front and back. A coil component (100) includes a planar coil pattern (10), a first resin layer (21) covering a first main surface (11) of the coil pattern, and a magnetic body (30) covering a second main surface (12) of the coil pattern. The coil pattern includes a terminal portion (10A) at an end portion, the first resin layer has a first opening portion (V1) in a portion overlapping a first main surface of the terminal portion, and the magnetic body has a second opening portion (V2) in a portion overlapping a second main surface of the terminal portion. The first main surface of the terminal portion has a first portion (A1) overlapping the first opening portion, and a second portion (A2) covered by the first resin layer. The second main surface of the terminal portion has a third portion (A3) overlapping the second opening portion, and a fourth portion (A4) covered by the magnetic body.

Description

Technical Field

[0001] The invention relates to a coil component. Background Art

[0002] Patent Document 1 discloses a coil component having a planar coil pattern that is electrically accessible from both the front and back sides.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2021-068841 Summary of the invention

[0006] However, the coil component described in Patent Document 1 may have insufficient strength at the terminal portion located at the end of the coil pattern.

[0007] Therefore, an object of the present invention is to improve the strength of a terminal portion in a coil component having a planar coil pattern that can be electrically connected from the front and back.

[0008] A coil component according to one embodiment of the present invention comprises: a planar coil pattern having a first principal surface and a second principal surface located on the opposite side of the first principal surface; a first resin layer covering the first principal surface of the coil pattern; a magnetic body covering the second principal surface of the coil pattern, wherein the coil pattern includes a terminal portion located at an end portion, the first resin layer having a first opening portion in a portion overlapping with the first principal surface of the terminal portion, the magnetic body having a second opening portion in a portion overlapping with the second principal surface of the terminal portion, the first principal surface of the terminal portion having a first portion overlapping with the first opening portion and a second portion covered by the first resin layer, and the second principal surface of the terminal portion having a third portion overlapping with the second opening portion and a fourth portion covered by the magnetic body.

[0009] According to the present invention, the strength of the terminal portion can be improved in a coil component having a planar coil pattern that can be electrically connected from both sides. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic plan view showing the appearance of a coil component 100 according to one embodiment of the present invention.

[0011] Figure 2 It means from Figure 1 This is a schematic plan view of the appearance of coil component 100 as viewed from the opposite side.

[0012] Figure 3 It is a schematic plan view showing a state where the magnetic body 30 is removed from the coil component 100 .

[0013] Figure 4 yes Figure 3 An enlarged view of area C is shown.

[0014] Figure 5 It is along Figure 4 A schematic cross-sectional view taken along line DD is shown.

[0015] Figure 6 This is a schematic cross-sectional view for explaining the structure of each member constituting coil component 100 in more detail.

[0016] Figure 7 yes Figure 6 A modification of the structure shown.

[0017] Figure 8 This is an enlarged view of the terminal portion 10A of the coil pattern 10 as viewed from the first principal surface 11 side.

[0018] Fig. 9 This is an enlarged view of the terminal portion 10A of the coil pattern 10 as viewed from the second main surface 12 side.

[0019] Explanation of symbols

[0020] 10 coil pattern

[0021] 10A, 10B terminal part

[0022] 11. First main surface

[0023] 12 Second main surface

[0024] 13 Side

[0025] 21 First resin layer

[0026] 22 Second resin layer

[0027] 30 Magnetic body

[0028] 31 First Area

[0029] 32 Second Area

[0030] 40 Third resin layer

[0031] 100 Coil parts

[0032] A1 Part 1

[0033] A2 Part 2

[0034] A3 Part 3

[0035] A4 Part 4

[0036] A11 First Area

[0037] A12 Second Area

[0038] Area C

[0039] L imaginary line

[0040] P Center

[0041] S space area

[0042] V1 First opening

[0043] V2 Second opening

[0044] V3 Third opening

[0045] V4 fourth opening. DETAILED DESCRIPTION

[0046] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0047] Figure 1 and Figure 2 It is a schematic plan view showing the appearance of the coil component 100 according to one embodiment of the present invention, and shows a state viewed from opposite sides.

[0048] like Figure 1 and Figure 2 As shown, the coil component 100 of this embodiment has a substantially circular planar shape when viewed from the Z direction, the magnetic body 30 is located on one surface, and the first resin layer 21 is located on the other surface. Figure 3 As shown in FIG. 1 , a planar coil pattern 10 is provided between the magnetic body 30 and the first resin layer 21. Figure 3 In the example shown, the coil pattern 10 is wound about 4 times in a plane spiral shape, and one end (inner peripheral end) of the coil pattern 10, that is, a part of the terminal portion 10A, and the other end (outer peripheral end) of the coil pattern 10, that is, a part of the terminal portion 10B are exposed on both sides of the coil component 100. Thus, the coil component 100 of the present embodiment can be electrically connected from the front and back, so the installation freedom is high and the convenience is excellent. In addition, the plane shape of the coil component 100 observed from the Z direction is not limited to a roughly circular shape, and can also be a roughly polygonal shape.

[0049] The planar shape of the terminal portions 10A and 10B is roughly circular, and its diameter is larger than the pattern width in the area outside the terminal portions 10A and 10B of the coil pattern 10. In addition, the pattern width in the area outside the terminal portions 10A and 10B of the coil pattern 10 is roughly constant at the position away from the terminal portions 10A and 10B, but is partially reduced in the portion surrounded by the terminal portions 10A and 10B. As a result, the overall planar size of the coil component 100 can be suppressed, while the area of ​​the opening area surrounded by the coil pattern 10 is fully ensured. That is, because the terminal portion 10A as the inner peripheral end is configured to invade the innermost circumference, the reduction in the area of ​​the opening area caused by the terminal portion 10A is suppressed. In addition, because the terminal portion 10B as the outer peripheral end is configured to invade the outermost circumference, the expansion of the overall planar size of the coil component 100 caused by the terminal portion 10B is suppressed. In addition, the pattern width of the coil pattern 10 is reduced in the portion where the terminal portions 10A and 10B invade.

[0050] Figure 4 yes Figure 3 The enlarged view of area C is shown. In addition, Figure 5 It is along Figure 4 A schematic cross-sectional view taken along line DD is shown.

[0051] like Figure 4 As shown, the portion of the coil pattern 10 surrounding the terminal portion 10A is bent more greatly to avoid the terminal portion 10A that is intruded into the configuration as the turns are closer to the inner circumference, and the bending amount is less as the turns are closer to the outer circumference. Furthermore, the outermost turns are almost not bent, and only the pattern width is reduced compared to other parts.

[0052] like Figure 5As shown, the coil pattern 10 has a first main surface 11 constituting an XY plane and located on the -Z direction side, and a second main surface 12 constituting an XY plane on the opposite side of the first main surface 11 and located on the +Z direction side. The first main surface 11 of the coil pattern 10 is covered by the first resin layer 21 via the third resin layer 40, except for a part of the terminal portions 10A and 10B. The second main surface 12 of the coil pattern 10 is covered by the magnetic body 30 via the second resin layer 22, except for a part of the terminal portions 10A and 10B. The first resin layer 21 and the second resin layer 22 may both have adhesive properties on both sides. The material of the first resin layer 21 is not particularly limited, and for example, an acrylic double-sided tape can be cited. The material of the second resin layer 22 is not particularly limited, and for example, an acrylic double-sided tape, an acrylic adhesive resin, etc. can be cited. The second resin layer 22 may also use a material containing a ceramic material or the like in an acrylic adhesive resin. When both surfaces of the second resin layer 22 have adhesive properties, the coil pattern 10 and the magnetic body 30 can be firmly bonded via the second resin layer 22. In addition, when both sides of the first resin layer 21 are adhesive, the coil component 100 of the present embodiment can be bonded to a mounted object such as a circuit substrate without using an adhesive agent. The material of the third resin layer 40 is not particularly limited, and for example, adhesive resins such as polyvinyl chloride resins, polycarbonate resins, polystyrene resins, polymethyl methacrylate resins, polyester resins, polysulfone resins, polyphenylene ether resins, polybutadiene resins, poly(N-vinyl carbazole) resins, hydrocarbon resins, ketone resins, phenoxy resins, polyamide resins, ethyl cellulose resins, vinyl acetate resins, ABS resins, polyurethane resins, melamine resins, acrylic resins, unsaturated polyester resins, alkyd resins, epoxy resins, and silicone resins can be cited. The third resin layer 40 can also use a material containing a conductive resin material in the adhesive resin.

[0053] exist Figure 5 In the example shown, the magnetic body 30 is composed of a magnetic sheet, and the first resin layer 21 and the second resin layer 22 are both composed of an acrylic double-sided tape. Figure 6 The example in which the magnetic body 30 is formed of a magnetic sheet, the first resin layer 21 is formed of an acrylic double-sided tape, and the second resin layer 22 is formed of an acrylic adhesive resin is shown. Figure 6In the case of the example shown, the second resin layer 22 composed of an acrylic adhesive resin acts as a filling layer for the space region S between the coil patterns 10. In this case, as for the thickness of the second resin layer 22, the thickness T4 of the portion overlapping the space region S between the coil patterns 10 is thicker than the thickness T3 of the portion overlapping the coil pattern 10. The thickness T4 of the second resin layer 22 located in the space region S may also be smaller than the thickness T0 of the coil pattern 10. Accordingly, the coil pattern 10 can obtain higher magnetic properties because at least a portion of the side surface 13 connecting the first main surface 11 and the second main surface 12 is covered by the magnetic body 30. Here, the thickness T0 of the coil pattern 10 may also be the total thickness of the third resin layer 40 and the coil pattern 10.

[0054] like Figure 6 As shown, the magnetic body 30 includes a first region 31 overlapping with the coil pattern 10, and a second region 32 overlapping with the space region S located between the coil patterns 10. The thickness T1 of the first region 31 may be substantially the same as the thickness T2 of the second region 32. When the thickness T1 of the first region 31 is substantially the same as the thickness T2 of the second region 32, the height difference T5 between the surface 31a of the first region 31 and the surface 32a of the second region 32 becomes T4-T3, which is smaller than the thickness T0 of the coil pattern 10. Thus, the flatness of the surface of the magnetic body 30 can be improved. The thicknesses T1 and T2 of the magnetic body 30 may be larger than the thickness T0 of the coil pattern 10. Thus, high magnetic properties can be obtained. In addition, the height of the surface 31a of the first region 31 and the height of the surface 32a of the second region 32 are heights based on the first resin layer 21.

[0055] As another way, Figure 7 As shown, the second resin layer 22 may also be omitted. Figure 6 The example shown is the same, the magnetic body 30 is made of a magnetic sheet, and the first resin layer 21 is made of an acrylic double-sided tape. In this case, the coil pattern 10 is directly covered by the magnetic body 30. In addition, since the entire side surface 13 of the coil pattern 10 is covered by the magnetic body 30, a further higher magnetic property can be obtained. Figure 7 In the example shown, the thickness T2 of the second region 32 may also be thicker than the thickness T1 of the first region 31 .

[0056] like Figure 5As shown, the first resin layer 21 and the third resin layer 40 have a first opening V1 and a fourth opening V4, respectively, in the portion overlapping with the first main surface 11 of the terminal portion 10A. In addition, the magnetic body 30 and the second resin layer 22 have a second opening V2 and a third opening V3, respectively, in the portion overlapping with the second main surface 12 of the terminal portion 10A. Thus, a portion of the first main surface 11 of the terminal portion 10A is exposed through the first opening V1 and the fourth opening V4. Similarly, a portion of the second main surface 12 of the terminal portion 10A is exposed through the second opening V2 and the third opening V3. A surface treatment layer composed of Ni / Au plating or the like may also be provided on the exposed portion of the terminal portion 10A.

[0057] Figure 8 This is an enlarged view of the terminal portion 10A of the coil pattern 10 as viewed from the first principal surface 11 side.

[0058] like Figure 8 As shown, the first main surface 11 of the terminal portion 10A has a first portion A1 overlapping with the first opening portion V1 of the first resin layer 21, and a second portion A2 that does not overlap with the first opening portion V1 and is covered by the first resin layer 21. The inner peripheral edge of the first opening portion V1 overlaps with the first main surface 11 of the terminal portion 10A throughout the entire circumference. In other words, the outer peripheral edge of the terminal portion 10A on the side of the first main surface 11 is covered by the first resin layer 21 throughout the entire circumference. As a result, the outer peripheral edge of the terminal portion 10A on the side of the first main surface 11 is not exposed from the first opening portion V1 and is covered by the first resin layer 21, so that the peeling of the terminal portion 10A is suppressed and the mechanical strength of the terminal portion 10A is ensured.

[0059] Furthermore, the inner peripheral edge of the fourth opening V4 of the third resin layer 40 overlaps the first portion A1 of the terminal portion 10A throughout the entire circumference. That is, the third resin layer 40 covers the inner peripheral edge of the first opening V1 throughout the entire circumference. As a result, the first portion A1 of the terminal portion 10A is divided into a first area A11 exposed from the fourth opening V4 and a second area A12 covered by the third resin layer 40. The first area A11 is the portion where the terminal portion 10A is exposed, and the second area A12 is the portion where the third resin layer 40 is exposed. In the case where the terminal portion 10A is provided with a surface treatment layer composed of Ni / Au plating or the like, the surface treatment layer is formed in the first area A11, but not in the second area A12. In this case, since the solder does not extend to the second area A12 during installation, the connection reliability is improved.

[0060] Here, assuming an imaginary line L extending radially from the center P of the substantially circular terminal portion 10A, the width W11 of the first region A11 along the imaginary line L may be larger than the width W12 of the second region A12 along the imaginary line L, and the width W2 of the second portion A2 along the imaginary line L. In this way, the exposed area of ​​the terminal portion 10A on the first main surface 11 side can be sufficiently ensured. In addition, the area of ​​the first region A11 of the terminal portion 10A exposed may be larger than the area of ​​the second region A12, may be larger than the area of ​​the second portion A2, or may be larger than the total area of ​​the second region A12 and the second portion A2.

[0061] Fig. 9 This is an enlarged view of the terminal portion 10A of the coil pattern 10 as viewed from the second main surface 12 side.

[0062] like Fig. 9 As shown in FIG. 1 , the second main surface 12 of the terminal portion 10A has a third portion A3 overlapping the second opening portion V2 of the magnetic body 30 and the third opening portion V3 of the second resin layer 22, and a fourth portion A4 not overlapping the second opening portion V2 and the third opening portion V3 but covered by the second resin layer 22 and the magnetic body 30. The plane positions of the inner peripheral edge of the second opening portion V2 and the inner peripheral edge of the third opening portion V3 may also be consistent. The inner peripheral edges of the second opening portion V2 and the third opening portion V3 overlap the second main surface 12 of the terminal portion 10A throughout the entire circumference. In other words, the outer peripheral edge of the terminal portion 10A on the second main surface 12 side is covered by the second resin layer 22 and the magnetic body 30 throughout the entire circumference. As a result, since the outer peripheral edge of the terminal portion 10A on the second main surface 12 side is not exposed from the second opening portion V2 and the third opening portion V3 but covered by the second resin layer 22 and the magnetic body 30, the peeling of the terminal portion 10A is suppressed and the mechanical strength of the terminal portion 10A is ensured.

[0063] Here, assuming an imaginary line L extending radially from the center P of the substantially circular terminal portion 10A, the width W3 of the third portion A3 along the imaginary line L may be larger than the width W4 of the fourth portion A4 along the imaginary line L. Accordingly, it is possible to sufficiently ensure the exposed area of ​​the terminal portion 10A on the second main surface 12 side. In addition, the area of ​​the exposed third portion A3 of the terminal portion 10A may be larger than the area of ​​the fourth portion A4.

[0064] In the above, the terminal portion 10A of the coil pattern 10 and the structure of its periphery are described in detail, but the terminal portion 10B of the coil pattern 10 and its periphery also have the same structure.

[0065] Thus, the coil component 100 of the present embodiment has a disk shape with the XY plane as the main surface, and can be connected to the coil pattern 10 from both sides in the Z direction, thereby improving the degree of freedom of installation. Moreover, the terminal portions 10A and 10B located at both ends of the coil pattern 10 are clamped from the Z direction by the first resin layer 21 and the magnetic body 30 because the peripheral edges are not exposed, so even if the thickness of the coil component 100 in the Z direction is thin, the mechanical strength of the terminal portions 10A and 10B can be fully ensured.

[0066] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention, and these modifications are naturally included in the scope of the present invention.

[0067] For example, the first resin layer 21 and the coil pattern 10 do not need to be in direct contact, and a base material made of a PET film or the like may be present therebetween. In this case, the base material made of a PET film or the like is removed at the portion covering the terminal portion 10A.

[0068] In addition, Figure 6 and Figure 7 In the example shown, when the magnetic body 30 is provided, a process for eliminating the step difference on the surface of the magnetic body 30 may be performed to further improve the flatness of the surface of the magnetic body 30 .

[0069] The technology involved in the present invention includes the following configuration examples, but is not limited thereto.

[0070] A coil component according to an embodiment of the present invention comprises: a planar coil pattern having a first main surface and a second main surface located on the opposite side of the first main surface; a first resin layer covering the first main surface of the coil pattern; a magnetic body covering the second main surface of the coil pattern, the coil pattern including a terminal portion located at an end portion, the first resin layer having a first opening portion in a portion overlapping with the first main surface of the terminal portion, the magnetic body having a second opening portion in a portion overlapping with the second main surface of the terminal portion, the first main surface of the terminal portion having a first portion overlapping with the first opening portion and a second portion covered by the first resin layer, and the second main surface of the terminal portion having a third portion overlapping with the second opening portion and a fourth portion covered by the magnetic body. Accordingly, the mechanical strength of the terminal portion can be ensured while electrical access can be made from the front and back.

[0071] In the above coil component, the coil pattern may further include a side surface connecting the first main surface and the second main surface, and the magnetic body may cover at least a portion of the side surface of the coil pattern. This can provide high magnetic properties.

[0072] In the coil component, the magnetic body may include a first region overlapping with the coil pattern and a second region overlapping with the space region between the coil patterns, and the height difference between the surface of the first region and the surface of the second region is smaller than the thickness of the coil pattern. Thus, the flatness of the surface of the magnetic body can be improved.

[0073] The coil component may further include a second resin layer between the second main surface of the coil pattern and the magnetic body, and the second resin layer may include a third opening overlapping the second opening. This allows electrical connection to be made to the second main surface of the terminal portion through the second and third openings.

[0074] In the above coil component, both the first and second resin layers may have adhesive properties on both sides. This allows the coil component to be bonded to a mounting object such as a circuit board.

[0075] In the coil component, the inner peripheral edge of the first opening may overlap the first main surface of the terminal portion over the entire circumference, and the inner peripheral edge of the second opening may overlap the second main surface of the terminal portion over the entire circumference. This can further improve the mechanical strength of the terminal portion.

[0076] Alternatively, the coil component further includes a third resin layer, the third resin layer being located between the first main surface of the coil pattern and the first resin layer and covering the inner peripheral edge of the first opening, and the third resin layer having a fourth opening that exposes the first portion. Accordingly, electrical connection can be made to the first main surface of the terminal portion via the first and fourth openings.

[0077] In the coil component described above, the first portion may include a first region exposed from the fourth opening and a second region covered by the third resin layer, and a width of the first region along an imaginary line extending radially from the center of the terminal portion is greater than a width of the second region along the imaginary line. Thus, the exposed area of ​​the first main surface side of the terminal portion can be sufficiently ensured.

[0078] In the above-mentioned coil component, the coil pattern may be wound multiple times in a plane spiral shape, and the pattern width of the coil pattern may be locally reduced in the portion wound along the terminal portion. Thus, a high inductance can be obtained, and the overall planar size of the coil component can be suppressed while fully ensuring the area of ​​the opening region surrounded by the coil pattern.

Claims

1. A coil component, wherein: have: A planar coil pattern having a first main surface and a second main surface located on the opposite side of the first main surface; a first resin layer covering the first main surface of the coil pattern; and a magnetic body covering the second main surface of the coil pattern, The coil pattern includes a terminal portion located at an end portion, The first resin layer has a first opening at a portion overlapping the first main surface of the terminal portion. The magnetic body has a second opening at a portion overlapping the second main surface of the terminal portion. The first main surface of the terminal portion has a first portion overlapping the first opening and a second portion covered by the first resin layer. The second main surface of the terminal portion includes a third portion overlapping the second opening and a fourth portion covered by the magnetic body.

2. The coil component according to claim 1, wherein The coil pattern further includes a side surface connecting the first main surface and the second main surface, The magnetic body covers at least a portion of the side surface of the coil pattern.

3. The coil component according to claim 2, wherein: The magnetic body includes a first region overlapping with the coil pattern and a second region overlapping with a space region between the coil patterns. A difference in height between a surface of the first region and a surface of the second region is smaller than a thickness of the coil pattern.

4. The coil component according to claim 1, wherein further comprising a second resin layer located between the second main surface of the coil pattern and the magnetic body, The second resin layer has a third opening overlapping with the second opening.

5. The coil component according to claim 4, wherein Both surfaces of the first resin layer and the second resin layer have adhesive properties.

6. The coil component according to claim 1, wherein The inner peripheral edge of the first opening overlaps the first main surface of the terminal portion over the entire circumference. An inner peripheral edge of the second opening portion overlaps the second main surface of the terminal portion over the entire circumference.

7. The coil component according to claim 6, wherein further comprising: a third resin layer located between the first main surface of the coil pattern and the first resin layer and covering the inner peripheral edge of the first opening; The third resin layer has a fourth opening that exposes the first portion.

8. The coil component according to claim 7, wherein The first portion includes a first region exposed from the fourth opening and a second region covered by the third resin layer. A width of the first region along an imaginary line extending in a radial direction from a center of the terminal portion is greater than a width of the second region along the imaginary line.

9. The coil component according to any one of claims 1 to 8, wherein: The coil pattern is wound multiple times in a planar spiral shape, The pattern width of the coil pattern is partially reduced at a portion surrounding the terminal portion.

Images