Coil components and their manufacturing methods

Abstract

The objective of the coil component of the present invention is to achieve a thin overall thickness and a high inductance value in a coil component having a structure in which spiral coil patterns are stacked. The coil component (1) includes: a coil portion (C) having an interlayer insulating film (51-55) and spirally wound coil patterns (CP1-CP4) alternately stacked in the axial direction; and magnetic elements (M1-M3) embedded in the coil portion (C). The interlayer insulating film (55) covering the coil pattern (CP4) located at one end in the axial direction has a higher permeability than the other interlayer insulating films (51-54). Thus, the coil pattern (CP4) located at the end is covered by the interlayer insulating film (55) with high permeability, thereby enabling a high inductance value while maintaining a thin overall thickness.

Description

Technical Field

[0001] This invention relates to coil components and methods for manufacturing the same, and more particularly to coil components having a structure with stacked spiral coil patterns and methods for manufacturing the same. Background Technology

[0002] As a coil component having a structure in which a spiral coil pattern is stacked, the coil component described in Patent Document 1 is known. The coil component described in Patent Document 1 has the following structure: the coil pattern is embedded in a first magnetic resin layer containing spherical magnetic filler, and the coil pattern is sandwiched in the stacking direction by a second magnetic resin layer containing flat magnetic filler.

[0003] Thus, in the coil component described in Patent Document 1, the coil pattern is embedded in the magnetic resin layer, thereby achieving a high inductance value.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-140202 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] However, in Patent Document 1, a second magnetic resin layer is disposed outside the first magnetic resin layer, which results in a large overall thickness of the coil component.

[0009] Therefore, the object of the present invention is to achieve a thin overall thickness and a high inductance value in a coil component having a structure with stacked spiral coil patterns and a method thereof.

[0010] Technical means for solving technical problems

[0011] The coil component of the present invention is characterized by comprising: a coil portion having a structure in which a plurality of interlayer insulating films and a plurality of coil patterns wound in a spiral shape are alternately stacked in the axial direction; and a magnetic element embedded in the coil portion, wherein the plurality of interlayer insulating films have a first interlayer insulating film and a second interlayer insulating film, the first interlayer insulating film covering a first coil pattern located at one end of the plurality of coil patterns from one end side in the axial direction, the second interlayer insulating film covering the remaining coil patterns of the plurality of coil patterns, and the first interlayer insulating film having a higher permeability than the second interlayer insulating film.

[0012] According to the present invention, the first coil pattern located at the end is covered by a first interlayer insulating film with high magnetic permeability, thus enabling a high inductance value to be obtained while keeping the overall thickness thin.

[0013] In this invention, the magnetic material may have a higher permeability than the first interlayer insulating film. This allows for a higher inductance value. However, using a material with a coefficient of thermal expansion close to that of the magnetic material as the first interlayer insulating film can also prevent delamination at the interface between the first interlayer insulating film and the magnetic material.

[0014] In this invention, the first interlayer insulating film may also be made of the same magnetic material as the magnetic body. Therefore, the first interlayer insulating film and the magnetic body have the same coefficient of thermal expansion, thus more effectively preventing delamination at the interface between the first interlayer insulating film and the magnetic body.

[0015] In this invention, the first interlayer insulating film may also be composed of a magnetic resin material in which magnetic fillers have been added, wherein the maximum particle size of the magnetic fillers is smaller than the pattern spacing of the first coil pattern. Thus, the magnetic fillers are inserted into the patterns of the first coil pattern, thereby achieving a higher inductance value.

[0016] In this invention, the magnetic filler may also comprise nanofillers composed of metallic magnetic materials with an average particle size of less than 1 μm. This allows the magnetic filler to more easily penetrate the patterns of the first coil pattern.

[0017] In this invention, the cross-section of the first coil pattern may also have a tapered shape that tapers towards one end in the axial direction. This allows the magnetic filler to more easily enter the spaces between the patterns of the first coil pattern.

[0018] In this invention, the coil portion may also include an electrode pattern located on a conductor layer identical to the pattern of the first coil, the electrode pattern being in contact with the insulating film between the first layers and exposed from the magnetic body. This improves the heat dissipation of the coil component.

[0019] In this invention, the multiple interlayer insulating films may also include a third interlayer insulating film. This third interlayer insulating film covers the second coil pattern located at the other end of the multiple coil patterns from the other end side of the axial direction. The third interlayer insulating film has a higher permeability than the second interlayer insulating film. Thus, the third coil pattern located at the end is covered by the third interlayer insulating film with high permeability, thereby achieving a high inductance value while maintaining a thin overall thickness.

[0020] The method for manufacturing a coil component of the present invention is characterized by comprising: a first step of forming a coil portion by alternately stacking a plurality of interlayer insulating films and a plurality of coil patterns wound in a spiral shape in an axial direction; and a second step of embedding a magnetic material into the coil portion, wherein the plurality of coil patterns includes a last formed first coil pattern and the remaining second coil patterns, the plurality of interlayer insulating films include a first and a second interlayer insulating film, the first step comprising: a step of alternately forming a second coil pattern and a second interlayer insulating film; and a step of covering the first coil pattern with a first interlayer insulating film after forming the first coil pattern, wherein the first interlayer insulating film has a higher magnetic permeability than the second interlayer insulating film.

[0021] According to the present invention, the first coil pattern located at the end is covered by a first interlayer insulating film with high magnetic permeability, thus enabling the fabrication of a coil component with a thin overall thickness and high inductance.

[0022] Invention Effects

[0023] As described above, according to the present invention, in the coil component having a structure with stacked spiral coil patterns and the manufacturing method thereof, it is possible to achieve a thin overall thickness and a high inductance value. Attached Figure Description

[0024] Figure 1 This is a general cross-sectional view illustrating the structure of the coil component 1 according to one embodiment of the present invention.

[0025] Figure 2 This is a partial cross-sectional view of coil section C.

[0026] Figure 3 This is a process diagram illustrating the manufacturing method of coil component 1.

[0027] Figure 4 This is a process diagram illustrating the manufacturing method of coil component 1.

[0028] Figure 5 This is a process diagram illustrating the manufacturing method of coil component 1.

[0029] Figure 6 This is a process diagram illustrating the manufacturing method of coil component 1.

[0030] Figure 7 This is a process diagram illustrating the manufacturing method of coil component 1.

[0031] Figure 8 This is a process diagram illustrating the manufacturing method of coil component 1.

[0032] Figure 9 This is a process diagram illustrating the manufacturing method of coil component 1.

[0033] Figure 10 This is a process diagram illustrating the manufacturing method of coil component 1.

[0034] Figure 11 This is a process diagram illustrating the manufacturing method of coil component 1.

[0035] Figure 12 This is a process diagram illustrating the manufacturing method of coil component 1.

[0036] Figure 13 This is a process diagram illustrating the manufacturing method of coil component 1.

[0037] Figure 14 This is a process diagram illustrating the manufacturing method of coil component 1.

[0038] Figure 15 This is a process diagram illustrating the manufacturing method of coil component 1.

[0039] Figure 16 This is a process diagram illustrating the manufacturing method of coil component 1.

[0040] Figure 17 This is a process diagram illustrating the manufacturing method of coil component 1.

[0041] Figure 18 This is a process diagram illustrating the manufacturing method of coil component 1.

[0042] Figure 19 This is a process diagram illustrating the manufacturing method of coil component 1.

[0043] Figure 20 This is a process diagram illustrating the manufacturing method of coil component 1.

[0044] Figure 21 This is a process diagram illustrating the manufacturing method of coil component 1.

[0045] Figure 22 This is a process diagram illustrating the manufacturing method of coil component 1.

[0046] Figure 23 This is a process diagram illustrating the manufacturing method of coil component 1.

[0047] Figure 24 This is a process diagram illustrating the manufacturing method of coil component 1.

[0048] Figure 25 This is a process diagram illustrating the manufacturing method of coil component 1.

[0049] Figure 26 This is a process diagram illustrating the manufacturing method of coil component 1.

[0050] Figure 27 This is a process diagram illustrating the manufacturing method of coil component 1. Detailed Implementation

[0051] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0052] Figure 1 This is a general cross-sectional view illustrating the structure of the coil component 1 according to one embodiment of the present invention.

[0053] In one embodiment of the present invention, the coil component 1 is a surface-mount chip component suitable for use as an inductor in a power supply circuit, such as... Figure 1 As shown, it includes magnetic elements M1 to M3 and coil portions C embedded in the magnetic elements M1 to M3. The structure of the coil portion C will be described later, but in this embodiment, four layers of conductor layers with a spiral coil pattern are stacked with an interlayer insulating film in between, thereby forming one coil conductor.

[0054] Magnetic elements M1 to M3 are composite components containing metallic magnetic fillers made of materials such as iron (Fe) or permalloy, and resin binders, forming a magnetic circuit that generates magnetic flux by allowing current to flow in the coil section C. Liquid or powdered epoxy resin is preferably used as the resin binder. The materials constituting magnetic elements M1 to M3 can be the same or different from each other. Here, magnetic element M1 is the portion embedded in the inner diameter region of the coil section C, and magnetic element M2 is the portion extending from one side of the axial direction (…). Figure 1 The portion of coil C covered by the lower side shown is where the magnetic element M3 is located, from the other side of the axial direction. Figure 1 The portion of the upper side (shown) that covers the coil section C.

[0055] like Figure 1 As shown, the coil section C has a structure in which interlayer insulating films 51-55 and conductor layers 10, 20, 30, and 40 are alternately stacked. Conductor layers 10, 20, 30, and 40 each have spiral coil patterns CP1-CP4, and the upper or lower surface of the coil patterns CP1-CP4 is covered by interlayer insulating films 51-55. The sides of the coil patterns CP1-CP4 are each partially covered by interlayer insulating films 52-55. Here, the upper and lower surfaces of the coil patterns CP1-CP4 refer to surfaces perpendicular to the coil axis, and the sides of the coil patterns CP1-CP4 refer to surfaces horizontal or inclined relative to the coil axis.

[0056] Coil patterns CP1 to CP4 are interconnected via through-holes formed in interlayer insulating films 52 to 54, thereby forming a coil conductor. Copper (Cu) is preferably used as the material for conductor layers 10, 20, 30, and 40. In this embodiment, interlayer insulating films 51 to 54 are made of non-magnetic materials, while the uppermost interlayer insulating film 55 is made of a magnetic material. That is, interlayer insulating film 55 has a higher magnetic permeability than interlayer insulating films 51 to 54. The lowermost interlayer insulating film 51 may also use the same magnetic material as interlayer insulating film 55.

[0057] Conductor layer 10 is the first conductor layer formed on the upper surface of magnetic body M2, separated by interlayer insulating film 51, and includes a seed layer S1 as a substrate. In conductor layer 10, a coil pattern CP1 with multiple spiral turns and two electrode patterns 11 and 12 are provided. The lower surface of coil pattern CP1 is covered by interlayer insulating film 51, and the sides and upper surface of coil pattern CP1 are covered by interlayer insulating film 52. Figure 1 As shown, in a specified cross-section, coil pattern CP1 is connected to electrode pattern 11. In contrast, electrode pattern 12 is provided independently of coil pattern CP1. Electrode patterns 11 and 12 are exposed from magnetic elements M1 to M3.

[0058] Conductor layer 20 is a second conductor layer formed on the upper surface of conductor layer 10, separated by interlayer insulating film 52, and includes a seed layer S2 as a substrate. A coil pattern CP2 with multiple spiral turns and two electrode patterns 21 and 22 are provided on conductor layer 20. The lower surface of coil pattern CP2 is covered by interlayer insulating film 52, and the sides and upper surface of coil pattern CP2 are covered by interlayer insulating film 53. Electrode patterns 21 and 22 are provided independently of coil pattern CP2. Electrode patterns 21 and 22 are exposed from magnetic elements M1 to M3.

[0059] Conductor layer 30 is a third conductor layer formed on the upper surface of conductor layer 20, separated by interlayer insulating film 53, and includes a seed layer S3 as a substrate. A coil pattern CP3 with multiple spiral turns and two electrode patterns 31 and 32 are provided on conductor layer 30. The lower surface of coil pattern CP3 is covered by interlayer insulating film 53, and the sides and upper surface of coil pattern CP3 are covered by interlayer insulating film 54. Electrode patterns 31 and 32 are provided independently of coil pattern CP3. Electrode patterns 31 and 32 are exposed from magnetic elements M1 to M3.

[0060] Conductor layer 40 is a fourth conductor layer formed on the upper surface of conductor layer 30, separated by interlayer insulating film 54, and includes a seed layer S4 as a substrate. A coil pattern CP4 with multiple spiral turns and two electrode patterns 41 and 42 are provided on conductor layer 40. The lower surface of coil pattern CP4 is covered by interlayer insulating film 54, and the sides and upper surface of coil pattern CP4 are covered by interlayer insulating film 55. Figure 1 As shown, in a specified cross-section, coil pattern CP4 is connected to electrode pattern 42. In contrast, electrode pattern 41 is provided independently of coil pattern CP4. Electrode patterns 41 and 42 are exposed from magnetic elements M1 to M3.

[0061] Furthermore, the inner peripheral ends of coil pattern CP1 and coil pattern CP2 are connected via a through conductor that is part of conductor layer 20 and penetrates interlayer insulating film 52. Similarly, the outer peripheral ends of coil pattern CP2 and coil pattern CP3 are connected via a through conductor that is part of conductor layer 30 and penetrates interlayer insulating film 53. Furthermore, the inner peripheral ends of coil pattern CP3 and coil pattern CP4 are connected via a through conductor that is part of conductor layer 40 and penetrates interlayer insulating film 54. Thus, coil patterns CP1 to CP4 are connected in series to form a coil conductor consisting of multiple turns. Additionally, electrode patterns 11, 21, 31, and 41 are used as one external terminal, and electrode patterns 12, 22, 32, and 42 are used as another external terminal.

[0062] The above describes the structure of the coil component 1 according to this embodiment. In this embodiment, since the coil portion C is embedded with magnetic elements M1 to M3, the magnetic elements M1 to M3 form a magnetic circuit, resulting in a high inductance value. Furthermore, since the interlayer insulating film 55 covering the uppermost coil pattern CP4 is made of a magnetic material, there is no need to add other magnetic layers, further improving the inductance value. In particular, when the interlayer insulating film 55 has a protrusion 55a extending into the inner diameter region, this portion becomes magnetoresistive, and the inductance value decreases. However, in the coil component 1 of this embodiment, the interlayer insulating film 55 is made of a magnetic material, so even when the interlayer insulating film 55 has a protrusion 55a, the decrease in inductance value can be suppressed. Moreover, when the same magnetic material as the interlayer insulating film 55 is used as the material for the lowermost interlayer insulating film 51, the decrease in inductance value caused by the protrusion 51a can be suppressed.

[0063] As the interlayer insulating film 55, a magnetic resin material in which magnetic fillers are added to the resin material can be used. Therefore, the magnetic properties and insulation can be adjusted by the type, amount, and particle size of the magnetic filler. To improve the magnetic properties of the interlayer insulating film 55, similar to the magnetic substrates M1 to M3, metallic magnetic fillers composed of iron (Fe), permalloy-based materials, etc., can be added. However, since the interlayer insulating film 55 is in direct contact with the coil pattern CP4, higher insulation than that of the magnetic substrates M1 to M3 is required. Examples of methods to improve the insulation of the interlayer insulating film 55 include reducing the amount of magnetic filler added to the resin material compared to the magnetic substrates M1 to M3, or making the particle size ratio of the magnetic filler added to the resin material smaller than that of the magnetic substrates M1 to M3. In this case, although the permeability of the interlayer insulating film 55 is lower than that of the magnetic substrates M1 to M3, it achieves higher permeability than conventional resin materials using non-magnetic materials, thus increasing the inductance value. Furthermore, as long as insulation can be ensured, the interlayer insulating film 55 can also be made of the same magnetic material as the magnetic bodies M1 to M3.

[0064] Furthermore, since the interlayer insulating film 55 is made of the same material as the magnetic bodies M1 and M3, the difference in their coefficients of thermal expansion can be suppressed. This prevents delamination at the interface between the interlayer insulating film 55 and the magnetic bodies M1 and M3. In particular, when the interlayer insulating film 55 is made of the same magnetic material as the magnetic bodies M1 and M3, their coefficients of thermal expansion are completely identical, making delamination at their interface extremely difficult to occur.

[0065] Here, it is preferable that the maximum particle size of the magnetic filler contained in the interlayer insulating film 55 is smaller than the pattern spacing of the coil pattern CP4. This allows the magnetic filler to penetrate the patterns of the coil pattern CP4, thus enabling a higher inductance value. In particular, when nanofillers composed of metallic magnetic materials with an average particle size of less than 1 μm are added, the nanofillers readily penetrate the patterns of the coil pattern CP4.

[0066] To facilitate the insertion of magnetic filler into the patterns of coil pattern CP4, as shown in the partial cross-sectional view... Figure 2As shown, the cross-section of coil pattern CP4 can be tapered. That is, when the pattern spacing at the bottom that contacts the interlayer insulating film 54 is set to W2, and the pattern spacing at the top on the opposite side of the bottom is set to W1, W1 > W2, and the tapered shape tapers from the bottom to the top. The other coil patterns CP1 to CP3 can also have a tapered shape. That is, when the pattern spacing at the bottom of coil patterns CP1 to CP3 is set to W4, and the pattern spacing at the top of coil patterns CP1 to CP3 is set to W3, W3 > W4. In this case, making the tapered shape of coil pattern CP4 larger, i.e., by making (W1 - W2) > (W3 - W4), the cross-sectional area of ​​coil patterns CP1 to CP3 can be sufficiently ensured, and the magnetic filler can easily enter the pattern spaces of coil pattern CP4.

[0067] The manufacturing method of the coil component 1 in this embodiment will now be described.

[0068] Figures 3 to 27 This is a process diagram illustrating the manufacturing method of the coil component 1 in this embodiment. Figures 3 to 27 The process diagram shown illustrates a cross section corresponding to one coil component 1, but in reality, a large number of coil components 1 can be manufactured simultaneously using a composite substrate for mass production.

[0069] First, a support 60 is prepared on which metal foils 62 and 63, such as copper (Cu), are disposed on the surface of the substrate 61. Figure 3 A release layer is provided at the interface between metal foil 62 and metal foil 63. Next, by patterning metal foil 63, protrusions 63a are formed on metal foil 63. Figure 4 ).

[0070] Next, an interlayer insulating film 51 and a metal foil 64 are formed on the surface of the metal foil 63 on which the protrusions 63a are provided. Figure 5 The interlayer insulating film 51 and the metal foil 64 can be formed by lamination. As a result, the shape of the protrusion 63a is transferred to the interlayer insulating film 51, forming a thick region 51A and a thin region 51B on the interlayer insulating film 51.

[0071] Next, after removing the metal foil 64 by etching ( Figure 6 Seed layer S1 is formed on the surface of interlayer insulating film 51 by chemical plating. Figure 7 Alternatively, the metal foil 64 can be used directly as the seed layer instead of forming the seed layer S1. However, it is desirable for the seed layer S1 to be as thin as possible. Therefore, it is preferable to re-form a thinner seed layer S1 after removing the metal foil 64.

[0072] Next, a resist pattern R1 is formed on the surface of the seed layer S1. Figure 8The resist pattern R1 is the negative pattern of the conductor layer 10. In this state, the seed layer S1 is grown by electroplating, thereby forming the conductor layer 10. Figure 9 At this point, a sacrificial pattern VP1 is formed in the inner diameter region of the coil pattern CP1. The position of the resist pattern R1 is adjusted so that the sacrificial pattern VP1 completely overlaps with the thin region 51A in the interlayer insulating film 51 and a portion of the thick region 51B.

[0073] Next, after stripping the resist pattern R1 ( Figure 10 The seed layer S1 exposed in the stripped portion of the resist pattern R1 is removed by etching. Figure 11 Thus, the coil pattern CP1 and the sacrificial pattern VP1 are electrically separated by a spiral gap SL. Next, an interlayer insulating film 52 and a metal foil 65 are formed on the surface of the conductor layer 10 by filling the gap SL. Figure 12 The interlayer insulating film 52 and the metal foil 65 can be formed by lamination. Next, a resist pattern R2 is formed on the surface of the metal foil 65. Figure 13 The resist pattern R2 is used as a mask to etch the metal foil 65. Figure 14 Therefore, the portion of the metal foil 65 that overlaps with the sacrificial pattern VP1 is removed.

[0074] Next, after stripping the resist pattern R2 ( Figure 15 The metal foil 65 is used as a mask for blasting, thereby exposing the sacrificial pattern VP1. Figure 16 Next, after removing the metal foil 65 ( Figure 17 An opening 52a is formed in the interlayer insulating film 52 by laser processing. Figure 18 Through the above processes, the conductor layer 10 and the interlayer insulating film 52 are formed.

[0075] Then, through repeated practice Figures 7-18 The process shown sequentially forms conductor layer 20, interlayer insulating film 53, conductor layer 30, interlayer insulating film 54, and conductor layer 40. Figure 19 In conductor layers 20, 30, and 40, sacrificial patterns VP2 to VP4 overlap with sacrificial pattern VP1. Next, an interlayer insulating film 55 is formed covering conductor layer 40. Figure 20 The interlayer insulating film 55 can be formed by coating a resin material incorporating magnetic fillers. Next, the sacrificial pattern VP4 is exposed by patterning the interlayer insulating film 55. Figure 21 In this state, the sacrificial patterns VP1 to VP4 are removed by wet etching. Figure 22Regarding the coil patterns CP1 to CP4, they are not etched because they are covered by interlayer insulating films 51 to 55. As a result, a space S is formed in the inner diameter region of the coil patterns CP1 to CP4.

[0076] Next, magnetic elements M1 and M3 are formed to fill the space S. Figure 23 Next, the support 60 is removed by peeling off the interface between metal foil 62 and metal foil 63, and the support 70 is then pasted upside down. Figure 24 ), by etching to remove metal foil 63 ( Figure 25 In this state, by performing an ashing process, the overall thickness of the interlayer insulating film 51 is reduced. Figure 26 The reduction in film thickness is adjusted so that the thinner region 51B is completely removed, and the thicker region 51A remains. As a result, the magnetic element M1 embedded in the inner diameter region of the coil section C is exposed.

[0077] Next, a magnetic matrix M2 is formed by covering an interlayer insulating film 51. Figure 27 Then, when the support 70 is peeled off and single-pieceed by cutting, Figure 1 The coil component 1 of this embodiment shown is now complete.

[0078] Thus, in this embodiment, the interlayer insulating film 55 is formed by coating a resin material containing magnetic filler. Therefore, compared with the case where the interlayer insulating films 51 to 55 are all made of non-magnetic materials, the overall thickness is not increased, and a high inductance value can be obtained.

[0079] Furthermore, in this embodiment, an interlayer insulating film 51 is laminated onto the surface of the metal foil 63 where the protrusions 63a are provided, thus transferring the shape of the protrusions 63a onto the interlayer insulating film 51. As a result, a thick region 51A and a thin region 51B are formed in the interlayer insulating film 51, thereby allowing for [the transfer of the film]. Figure 26 The ashing process shown allows for a thinner interlayer insulating film 51. This enables the coil component 1 to be made thinner.

[0080] The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments. Various modifications can be made without departing from the spirit of the present invention, and these modifications are also included within the scope of the present invention, which is self-evident.

[0081] Explanation of reference numerals in the attached figures

[0082] 1. Coil Components

[0083] 10, 20, 30, 40 conductor layers

[0084] Electrode patterns 11, 12, 21, 22, 31, 32, 41, 42

[0085] 51-55 interlayer insulating film

[0086] 51A Thick Film Area

[0087] 51B film thickness region

[0088] 51a Protrusion

[0089] 52a Opening

[0090] 55a Protrusion

[0091] 60 Support body

[0092] 61 Substrate

[0093] 62~65 metal foil

[0094] 63a Protrusion

[0095] 70 Support body

[0096] C Coil Section

[0097] CP1~CP4 coil patterns

[0098] M1~M3 Magnetic Element

[0099] R1 and R2 resist patterns

[0100] S Space

[0101] Seed layers S1 to S4

[0102] SL gap

[0103] VP1~VP4 Sacrifice patterns.

Claims

1. A coil component, characterized in that, include: The coil section has a structure in which multiple interlayer insulating films and multiple coil patterns wound in a spiral shape are alternately stacked in the axial direction; and A magnetic element embedded in the coil portion. The plurality of coil patterns includes: a first coil pattern located at one end of the axial direction, a second coil pattern located at the other end of the axial direction, and one or more third coil patterns located between the first coil pattern and the second coil pattern. The first coil pattern, the second coil pattern, and the third coil pattern all have a side surface and an upper surface located at one end side along the axial direction. The plurality of interlayer insulating films include a first interlayer insulating film, a second interlayer insulating film, and a third interlayer insulating film. The first interlayer insulating film covers the side surface and the top surface of the first coil pattern, the second interlayer insulating film covers the side surface and the top surface of the second coil pattern, and the third interlayer insulating film covers the side surface and the top surface of the third coil pattern. The magnetic element comprises a first portion embedded in the inner diameter region of the coil portion, a second portion covering the coil portion from the other end side of the axial direction, and a third portion covering the coil portion from the one end side of the axial direction. The first interlayer insulating film has higher magnetic permeability than the third interlayer insulating film. The magnetic element has higher magnetic permeability compared to the first interlayer insulating film. The first interlayer insulating film has higher insulation properties than the magnetic element.

2. The coil component as described in claim 1, characterized in that: The first interlayer insulating film has a higher magnetic permeability than the second interlayer insulating film.

3. The coil component as described in claim 1, characterized in that: The first interlayer insulating film has a protrusion that extends into the inner diameter region.

4. The coil component as described in claim 1, characterized in that: The first interlayer insulating film is composed of a magnetic resin material in which magnetic fillers have been added. The maximum particle size of the magnetic filler is smaller than the pattern spacing of the first coil pattern.

5. The coil component as described in claim 4, characterized in that: The magnetic filler comprises nanofillers composed of metallic magnetic materials with an average particle size of less than 1 μm.

6. The coil component as described in claim 4, characterized in that: The cross-section of the first coil pattern has a tapered shape that tapers towards one end of the axial direction.

7. The coil component as claimed in claim 1, characterized in that: The coil portion includes an electrode pattern located on a conductor layer identical to the pattern of the first coil. The electrode pattern is in contact with the first interlayer insulating film and is exposed from the magnetic body.

8. The coil component as claimed in any one of claims 1 to 7, characterized in that: The plurality of interlayer insulating films also include a fourth interlayer insulating film, which covers the second coil pattern from the other end side of the axial direction. The fourth interlayer insulating film has a higher magnetic permeability compared to the second and third interlayer insulating films.

9. A method for manufacturing a coil component, characterized in that, include: The first process involves forming a coil section by alternately stacking multiple interlayer insulating films and multiple coil patterns wound in a spiral shape in the axial direction; and The second step involves embedding a magnetic material into the coil portion. The plurality of coil patterns includes an initially formed second coil pattern, a last formed first coil pattern, and one or more third coil patterns formed after the formation of the second coil pattern and before the formation of the first coil pattern. The first coil pattern, the second coil pattern, and the third coil pattern all have a side surface and an upper surface located at one end of the axial direction. The plurality of interlayer insulating films include a first interlayer insulating film, a second interlayer insulating film, and a third interlayer insulating film. The first interlayer insulating film covers the side surface and the top surface of the first coil pattern, the second interlayer insulating film covers the side surface and the top surface of the second coil pattern, and the third interlayer insulating film covers the side surface and the top surface of the third coil pattern. The first step includes: covering the side surface and the top surface of the second coil pattern with the second interlayer insulating film, covering the side surface and the top surface of the third coil pattern with the third interlayer insulating film, and covering the side surface and the top surface of the first coil pattern with the first interlayer insulating film. The magnetic element comprises a first portion embedded in the inner diameter region of the coil portion, a second portion covering the coil portion from the other end side of the axial direction, and a third portion covering the coil portion from the one end side of the axial direction. The first interlayer insulating film has higher magnetic permeability than the third interlayer insulating film. The magnetic element has higher magnetic permeability compared to the first interlayer insulating film. The first interlayer insulating film has higher insulation properties than the magnetic element.

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