Coil component and method of manufacturing the same

Abstract

The technical problem of the present application is to improve the magnetic characteristics of a coil component having a structure in which an interlayer insulating film is provided between a spiral coil pattern and a magnetic body. The coil component (1) of the present application includes an interlayer insulating film (41) covering a coil pattern (CP1-CP3) from one side in the axial direction, a magnetic body (M1) embedded in an inner diameter region of the coil pattern (CP1-CP3), and a magnetic body (M2) covering the coil pattern (CP1-CP3) from the one side in the axial direction via the interlayer insulating film (41). The interlayer insulating film (41) has a protruding portion (41A) protruding in the radial direction toward the inner diameter region, and the protruding portion (41A) is bent toward the other side in the axial direction. In this way, the protruding portion (41A) is bent in the axial direction, and thus the entrance of a magnetic path located in the inner diameter region is wider than in the case where the protruding portion (41A) protrudes linearly toward the inner diameter region. Therefore, the decrease in the magnetic characteristics caused by the protruding portion (41A) is suppressed.

Description

TECHNICAL FIELD

[0001] The present application relates to a coil component and a manufacturing method thereof, and particularly relates to a coil component having a structure in which a spiral coil pattern is covered with a magnetic body and a manufacturing method thereof. BACKGROUND

[0002] A chip-type coil component having a spiral coil pattern is sometimes covered with a magnetic body in order to increase inductance. For example, in Patent Literature 1, a coil component having a structure in which a spiral coil pattern is covered with a magnetic body is disclosed.

[0003] However, the material constituting the magnetic body is insufficient in insulation compared with a resin material or the like. Therefore, a structure is adopted in which the coil pattern is not directly covered with the magnetic body, but is covered with an interlayer insulating film composed of a resin material, and further the surface thereof is covered with the magnetic body.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2017-11185 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] When the interlayer insulating film is provided between the coil pattern and the magnetic body, as described in Patent Literature 1, a part of the interlayer insulating film protrudes toward the inner diameter region of the coil pattern. In particular, when the interlayer insulating film at the end portion in the axial direction protrudes greatly toward the inner diameter region, the inlet of the magnetic path located in the inner diameter region becomes narrow in correspondence therewith, and there is a problem that the magnetic characteristics are degraded.

[0009] Therefore, an object of the present application is to suppress degradation of magnetic characteristics due to protrusion of the interlayer insulating film toward the inner diameter region in a coil component having a structure in which an interlayer insulating film is provided between a spiral coil pattern and a magnetic body. Further, an object of the present application is to provide a manufacturing method of such a coil component.

[0010] MEANS FOR SOLVING THE PROBLEMS

[0011] The coil component of the present application is characterized by comprising: a spiral coil pattern; a first interlayer insulating film covering the coil pattern from one side in the axial direction; and a magnetic body including a first portion embedded in an inner diameter region of the coil pattern, and a second portion covering the coil pattern from the one side in the axial direction with the first interlayer insulating film interposed therebetween, the first interlayer insulating film having a first protruding portion protruding radially toward the inner diameter region, the first protruding portion being curved toward the other side in the axial direction.

[0012] According to the present application, since the first protruding portion is bent toward the axial direction, the entrance of the magnetic path in the inner diameter region is wider than when protruding linearly toward the inner diameter region. Therefore, the decrease in magnetic characteristics due to the first protruding portion can be suppressed.

[0013] Also, the coil component of the present application can further include a second interlayer insulating film covering the coil pattern from the other side in the axial direction, and the magnetic body can further include a third portion covering the coil pattern from the other side in the axial direction through the second interlayer insulating film. Thus, higher magnetic characteristics can be obtained.

[0014] Also, the coil component of the present application can further include first and second external terminals connected to one end and the other end of the coil pattern, respectively, through openings provided in the second interlayer insulating film, and the first interlayer insulating film can have a smaller thickness than the second interlayer insulating film. Thus, the first interlayer insulating film on the opposite side from the external terminals has a small thickness, and thus the coil component can be made low in height.

[0015] In the present application, the second protruding portion can protrude toward the radial direction toward the inner diameter region, and the second protruding portion can be bent toward one side in the axial direction. Thus, the second protruding portion is bent toward the axial direction, and the entrance of the magnetic path in the inner diameter region is wider than when protruding linearly toward the inner diameter region. Therefore, the decrease in magnetic characteristics due to the protruding portion can be suppressed.

[0016] In the present application, the first protruding portion can be bent more than the second protruding portion. Thus, the decrease in magnetic characteristics due to the first protruding portion can be further suppressed.

[0017] In the present application, the magnetic body can be a composite member including a magnetic filler and a resin binder, and the protruding amount of the first protruding portion can be smaller than the maximum diameter of the magnetic filler. Thus, voids are less likely to occur in the vicinity of the first protruding portion.

[0018] The manufacturing method of the coil component of the present application includes: a first step of forming a coil pattern wound in a spiral shape and covered on one side in the axial direction by an interlayer insulating film; a second step of forming a protruding portion protruding toward the radial direction toward an inner diameter region of the coil pattern on the interlayer insulating film; and a third step of embedding a magnetic body in the inner diameter region of the coil pattern and covering the coil pattern on one side in the axial direction by the magnetic body through the interlayer insulating film, and in the third step, the magnetic body is pressed toward the other side in the axial direction so that the first protruding portion is bent toward the other side in the axial direction.

[0019] According to the present application, the protruding portion is bent by pressing the magnetic body, and thus the entrance of the magnetic path in the inner diameter region can be widened. Therefore, the decrease in magnetic characteristics due to the protruding portion can be suppressed.

[0020] In the present application, the first process can include a process of forming the interlayer insulating film in a manner that the thick region and the thin region are included in a portion coinciding with the inner diameter region of the coil pattern as viewed in the axial direction, and the second process removes the thin region of the interlayer insulating film by reducing the film thickness of the interlayer insulating film as a whole, thereby forming the protrusion. Thus, the thickness of the protrusion can be thinned, and thus the protrusion can be bent more greatly.

[0021] Effects of the Invention

[0022] Thus, according to the present application, the decrease in the magnetic characteristics caused by the protrusion of the interlayer insulating film toward the inner diameter region can be suppressed in the coil member having the structure in which the spiral coil pattern is covered with the magnetic body. Further, according to the present application, the manufacturing method of the coil member can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a schematic cross-sectional view for explaining the structure of a coil member 1 according to one embodiment of the present application.

[0024] Figure 2 is a schematic plan view for explaining the appearance of the coil member 1 as viewed in the axial direction.

[0025] Figure 3 is a schematic plan view for explaining the pattern shape of a conductor layer 10.

[0026] Figure 4 is a schematic plan view for explaining the pattern shape of a conductor layer 20.

[0027] Figure 5 is a schematic plan view for explaining the pattern shape of a conductor layer 30.

[0028] Figure 6 is a process diagram for explaining a manufacturing method of the coil member 1.

[0029] Figure 7 is a process diagram for explaining a manufacturing method of the coil member 1.

[0030] Figure 8 is a process diagram for explaining a manufacturing method of the coil member 1.

[0031] Figure 9 is a process diagram for explaining a manufacturing method of the coil member 1.

[0032] Figure 10 is a process diagram for explaining a manufacturing method of the coil member 1.

[0033] Figure 11 is a process diagram for explaining a manufacturing method of the coil member 1.

[0034] Figure 12 is a process chart for explaining the manufacturing method of the coil member 1.

[0035] Figure 13 is a process chart for explaining the manufacturing method of the coil member 1.

[0036] Figure 14 is a process chart for explaining the manufacturing method of the coil member 1.

[0037] Figure 15 is a process chart for explaining the manufacturing method of the coil member 1.

[0038] Figure 16 is a process chart for explaining the manufacturing method of the coil member 1.

[0039] Figure 17 is a process chart for explaining the manufacturing method of the coil member 1.

[0040] Figure 18 is a process chart for explaining the manufacturing method of the coil member 1.

[0041] Figure 19 is a process chart for explaining the manufacturing method of the coil member 1.

[0042] Figure 20 is a process chart for explaining the manufacturing method of the coil member 1.

[0043] Figure 21 is a process chart for explaining the manufacturing method of the coil member 1.

[0044] Figure 22 is a process chart for explaining the manufacturing method of the coil member 1.

[0045] Figure 23 is a process chart for explaining the manufacturing method of the coil member 1.

[0046] Figure 24 is a process chart for explaining the manufacturing method of the coil member 1.

[0047] Figure 25 is a process chart for explaining the manufacturing method of the coil member 1.

[0048] Figure 26 is a process chart for explaining the manufacturing method of the coil member 1.

[0049] Figure 27 is a process chart for explaining the manufacturing method of the coil member 1.

[0050] Figure 28 is a process chart for explaining the manufacturing method of the coil member 1.

[0051] Figure 29 is a process diagram for explaining a manufacturing method of the coil component 1.

[0052] Figure 30 is a process diagram for explaining a manufacturing method of the coil component 1.

[0053] Figure 31 is a process diagram for explaining a manufacturing method of the coil component 1.

[0054] Figure 32 is a process diagram for explaining a manufacturing method of the coil component 1.

[0055] Figure 33 is a process diagram for explaining a manufacturing method of the coil component 1.

[0056] Figure 34 is a process diagram for explaining a manufacturing method of the coil component 1. DETAILED DESCRIPTION

[0057] Hereinafter, a preferred embodiment of the present application will be described in detail with reference to the accompanying drawings.

[0058] Figure 1 is a schematic cross-sectional view for explaining a structure of the coil component 1 of one embodiment of the present application. Further, Figure 2 is a schematic plan view which shows an appearance of the coil component 1 as viewed from an axial direction.

[0059] The coil component 1 of one embodiment of the present application is a surface-mount type chip component which is preferably used as an inductor for a power supply circuit, as shown in FIG. 1A. Figure 1 and Figure 2 As shown in FIG. 1A, the coil component 1 includes magnetic bodies M1 to M3 and a coil portion C which is embedded in the magnetic bodies M1 to M3. The structure of the coil portion C will be described later, and in this embodiment, three layers of conductor layers each having a spiral coil pattern are stacked, whereby one coil conductor is formed. Further, one end of the coil conductor is connected to a first external terminal E1, and the other end of the coil conductor is connected to a second external terminal E2.

[0060] The magnetic bodies M1 to M3 are composite members which include a metal magnetic filler composed of iron (Fe), a permalloy-based material, or the like, and a resin binder, and constitute a magnetic path of magnetic flux generated by current flowing in the coil portion C. As the resin binder, liquid or powder epoxy resin is preferably used. The materials constituting the magnetic bodies M1 to M3 can be the same as or different from each other. Here, the magnetic body M1 is a portion (first portion) which is embedded in an inner diameter region of the coil portion C, the magnetic body M2 is a portion (second portion) which covers the coil portion C from one side in the axial direction, and the magnetic body M3 is a portion (third portion) which covers the coil portion C from the other side in the axial direction.

[0061] As Figure 1 shown, the coil portion C has a structure in which the interlayer insulating films 41 to 44 and the conductor layers 10, 20, 30 are alternately laminated. The conductor layers 10, 20, 30 each have a spiral coil pattern CP1 to CP3, and the upper surface or the lower surface of the coil pattern CP1 to CP3 is covered with the interlayer insulating film 41 to 44. The side surface of the coil pattern CP1 to CP3 is covered with a part of the interlayer insulating film 42 to 44, respectively. Here, the upper surface and the lower surface of the coil pattern CP1 to CP3 refer to surfaces perpendicular to the coil axis, and the side surface of the coil pattern CP1 to CP3 refers to a surface horizontal to the coil axis.

[0062] The coil patterns CP1 to CP3 constitute the coil portion C by being connected to each other via the through holes formed in the interlayer insulating films 42, 43. As the material of the conductor layers 10, 20, 30, copper (Cu) is preferably used. As for the interlayer insulating films 41 to 44, at least the interlayer insulating films 42, 43 use a non-magnetic material. As for the interlayer insulating film 41 located at the lowermost layer and the interlayer insulating film 44 located at the uppermost layer, a magnetic material can also be used.

[0063] The conductor layer 10 is a first layer conductor layer formed on the upper surface of the magnetic body M2 with the interlayer insulating film 41 interposed therebetween, and includes a seed layer S1 as a base. As Figure 3 shown, in the conductor layer 10, the coil pattern CP1 wound spirally by 0.5 turns and the two electrode patterns 11, 12 are provided. The lower surface of the coil pattern CP1 is covered with the interlayer insulating film 41, and the side surface and the upper surface of the coil pattern CP1 are covered with the interlayer insulating film 42. As Figure 1 and Figure 3 shown, in a prescribed cross section, the coil pattern CP1 and the electrode pattern 11 are connected. In contrast, the electrode pattern 12 is provided independently of the coil pattern CP1. The electrode pattern 11 is exposed from the magnetic body M3, and the surface thereof serves as a side electrode at the same potential as the external terminal E1. Similarly, the electrode pattern 12 is exposed from the magnetic body M3, and the surface thereof serves as a side electrode at the same potential as the external terminal E2.

[0064] The conductor layer 20 is a second layer conductor layer formed on the upper surface of the conductor layer 10 with the interlayer insulating film 42 interposed therebetween, and includes a seed layer S2 as a base. As Figure 4As shown, a coil pattern CP2 with 0.5 turns spirally wound and two electrode patterns 21 and 22 are provided in the conductor layer 20. The lower surface of the coil pattern CP2 is covered by an interlayer insulating film 42, and the side and upper surfaces of the coil pattern CP2 are covered by an interlayer insulating film 43. Electrode patterns 21 and 22 are provided independently of the coil pattern CP2. Electrode pattern 21 is exposed from the magnetic body M3, and its surface is used as a side electrode with the same potential as the external terminal E1. Similarly, electrode pattern 22 is exposed from the magnetic body M3, and its surface is used as a side electrode with the same potential as the external terminal E2.

[0065] Conductor layer 30 is a third conductor layer formed on the upper surface of conductor layer 20, separated by an interlayer insulating film 43, and includes a seed layer S3 as a substrate. Figure 5 As shown, a coil pattern CP3 with 0.5 turns spirally wound and two electrode patterns 31 and 32 are provided in the conductor layer 30. The lower surface of the coil pattern CP3 is covered by an interlayer insulating film 43, and the sides and upper surface of the coil pattern CP3 are covered by an interlayer insulating film 44. Figure 1 As shown, in a specified cross-section, coil pattern CP3 is connected to electrode pattern 32. In contrast, electrode pattern 31 is independently disposed from coil pattern CP3. Electrode pattern 31 protrudes from magnetic body M3, its surface serving as a side electrode at the same potential as external terminal E1. Similarly, electrode pattern 32 protrudes from magnetic body M3, its surface serving as a side electrode at the same potential as external terminal E2.

[0066] Furthermore, coil patterns CP1 and CP2 are connected via through-hole conductors 51, which are part of conductor layer 20 and penetrate the interlayer insulating film 42. Additionally, coil patterns CP2 and CP3 are connected via through-hole conductors 52, which are part of conductor layer 30 and penetrate the interlayer insulating film 43. Thus, a coil conductor with 1.5 turns is formed by coil patterns CP1 to CP3. Furthermore, electrode patterns 11, 21, and 31 are connected to external terminal E1 via through-hole conductors 53 to 55, and electrode patterns 12, 22, and 32 are connected to external terminal E2 via through-hole conductors 56 to 58. Thus, a structure is obtained where one end of the coil conductor formed by coil patterns CP1 to CP3 is connected to external terminal E1, and the other end is connected to external terminal E2.

[0067] In this embodiment, the thickness of the interlayer insulating film 41 is thinner than that of the interlayer insulating films 42 to 44, thereby achieving a lower height. In order to carry out the various processes described later, the thickness of the interlayer insulating films 41 to 44 needs to be a certain degree, but for the interlayer insulating film 41 located at the bottom layer, the thickness can be reduced by ashing or the like after the coil part C is made and before the magnetic element M2 is formed, so it can be thinner than the interlayer insulating films 42 to 44.

[0068] Furthermore, in this embodiment, a portion of the interlayer insulating films 41 to 44 protrudes into the inner diameter region of the coil portion C. Specifically, the protrusion 41A, which is part of the interlayer insulating film 41, and the protrusion 44A, which is part of the interlayer insulating film 44, have a shape that curves towards the center of the coil portion C. That is, the protrusion 41A curves towards the magnetic element M3. Figure 1 The upward bend is such that the protrusion 44A faces the magnetic body M2. Figure 1 The interlayer insulating films 41 and 44 are bent downwards. As a result, compared with the case where the protrusions 41A and 44A protrude straight in the radial direction, the opening diameter of the interlayer insulating films 41 and 44 is increased, thus improving the magnetic properties.

[0069] Furthermore, in this embodiment, the bending angle θ1 of the protrusion 41A is greater than the bending angle θ4 of the protrusion 44A (θ1 > θ4). That is, the protrusion 41A is bent more significantly than the protrusion 44A. Such a structure can be obtained by making the film thickness of the interlayer insulating film 41 thinner than the film thickness of the interlayer insulating films 42-44. By making the protrusion 41A bend more significantly, the opening diameter of the interlayer insulating film 41 is made larger, thereby further improving the magnetic properties.

[0070] Furthermore, due to the curvature of protrusions 41A and 44A, the corner 41B where protrusion 41A meets the vertical portion of the interlayer insulating film 42 becomes narrower, and the corner 44B where protrusion 44A meets the vertical portion of the interlayer insulating film 44 becomes narrower. Therefore, it is less likely for large-diameter magnetic fillers to enter the corners 41B and 44B, thus suppressing voids caused by large-diameter magnetic fillers entering the corners 41B and 44B. In particular, the protrusion amount of protrusions 41A and 44A is preferably less than the maximum diameter of the magnetic fillers contained in the magnetic bodies M1 to M3. Therefore, voids are even less likely to occur at the corners 41B and 44B.

[0071] Next, the manufacturing method of the coil component 1 in this embodiment will be described.

[0072] Figures 6-34 This is a process diagram illustrating the manufacturing method of the coil component 1 in this embodiment. Figures 6-34 The process diagram shown illustrates a cross section corresponding to one coil component 1. In reality, multiple coil components 1 can be obtained by simultaneously fabricating multiple coil components 1 using a composite substrate.

[0073] First, a support 60 is prepared on the surface of the substrate 61, on which metal foils 62 and 63 such as copper (Cu) are disposed. Figure 6 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 7 ).

[0074] Next, the interlayer insulating film 41 and the metal foil 64 are formed on the surface of the metal foil 63 provided with the protrusion 63a. Figure 8 The interlayer insulating film 41 and the metal foil 64 can be formed by a lamination method. As a result, the shape of the protrusion 63a is transferred to the interlayer insulating film 41, and the region 41C having a thick film thickness and the region 41D having a thin film thickness are formed in the interlayer insulating film 41.

[0075] Next, after the metal foil 64 is removed by etching ( Figure 9 ), a seed layer S1 is formed on the surface of the interlayer insulating film 41 by electroless plating ( Figure 10 ). Instead of forming the seed layer S1, the metal foil 64 can be directly used as the seed layer, but since it is desirable that the seed layer S1 be as thin as possible, it is preferable that a thinner seed layer S1 be newly formed after the metal foil 64 is removed.

[0076] Next, a resist pattern R1 is formed on the surface of the seed layer S1 ( Figure 11 ). The resist pattern R1 is a negative pattern of the conductor layer 10. By growing the seed layer S1 by electroplating in this state, the conductor layer 10 is formed ( Figure 12 ). At this time, the sacrificial pattern VP1 is formed in the inner diameter region and the outer region of the coil pattern CP1. The position of the resist pattern R1 is adjusted so that the portion of the sacrificial pattern VP1 located in the inner diameter region of the coil pattern CP1 is completely overlapped with the region 41D having a thin film thickness in the interlayer insulating film 41, and partially overlapped with the region 41C having a thick film thickness.

[0077] Next, after the resist pattern R1 is peeled off ( Figure 13 ), the seed layer S1 exposed at the peeled portion of the resist pattern R1 is removed by etching ( Figure 14 ). As a result, the coil pattern CP1 and the sacrificial pattern VP1 are electrically separated by the spiral-shaped slit SL. Next, the interlayer insulating film 42 and the metal foil 65 are formed on the surface of the conductor layer 10 so as to fill the slit SL ( Figure 15 ). The interlayer insulating film 42 and the metal foil 65 can be formed by a lamination method. Next, a resist pattern R2 is formed on the surface of the metal foil 65 ( Figure 16 ), and the metal foil 65 is etched with the resist pattern R2 as a mask ( Figure 17 ). As a result, the metal foil 65 in the portion overlapped with the sacrificial pattern VP1 is removed.

[0078] Next, after the resist pattern R2 is peeled off ( Figure 18 ), blasting processing is performed with the metal foil 65 as a mask, and the sacrificial pattern VP1 is exposed ( Figure 19 ). Next, after the metal foil 65 is removed ( Figure 20An opening 42a is formed in the interlayer insulating film 42 by laser processing. The opening 42a is located where it should be formed. Figure 3 The through-hole conductors 51, 53, and 56 are shown. Through the above processes, the conductor layer 10 and the interlayer insulating film 42 are formed.

[0079] Then, through repetition Figures 10-21 The process shown involves sequentially forming conductor layer 20, interlayer insulating film 43, conductor layer 30, and interlayer insulating film 44. Next, a seed layer S4 is formed on the surface of interlayer insulating film 44. Figure 22 A barrier pattern R3 is formed on the surface of the seed layer S4. Figure 23 In this state, the seed layer S4 is grown by electroplating to form external terminals E1 and E2. Figure 24 Next, the barrier pattern R3 is peeled off, and the seed layer S4 exposed in the peeled portion of the barrier pattern R3 is removed by etching. Figure 25 ).

[0080] Next, cover the external terminals E1 and E2 with the blocking pattern R4. Figure 26 ), and by performing wet etching in this state, the sacrificial patterns VP1 to VP3 are removed. Figure 27 The coil patterns CP1 to CP3 are not etched because they are covered by interlayer insulating films 41 to 44. As a result, a space S is formed in the inner diameter region and the outer region of the coil patterns CP1 to CP3.

[0081] Next, magnetic elements M1 and M3 are formed to fill the space S. Figure 28 During the formation of magnetic elements M1 and M3, they are forcefully pressed towards the support 60 without creating gaps. As a result, the protrusion 44A, which is part of the interlayer insulating film 44, bends in the pressing direction. Next, the support 60 is removed by peeling off the interface between the metal foil 62 and the metal foil 63. Furthermore, the external terminals E1 and E2 are exposed by grinding the surface of the magnetic element M3. Figure 29 Next, flip it over and paste the support body 70. Figure 30 ), by etching to remove metal foil 63 ( Figure 31 By performing ashing treatment in this state, the overall thickness of the interlayer insulating film 41 is reduced. Figure 32 The amount of reduction in film thickness is adjusted so that the thin film region 41D is completely removed and the thick film region 41C remains. As a result, the magnetic element M1 in the inner diameter region of the embedded coil portion C is exposed, and a protrusion 41A is formed in the interlayer insulating film 41.

[0082] Next, a magnetic matrix M2 is formed by covering an interlayer insulating film 41. Figure 33). In the formation of the magnetic body M2, the magnetic body M2 is pressed strongly toward the support 70 side in a manner that does not generate a gap or the like. Thus, the protruding portion 41A that is a part of the interlayer insulating film 41 is bent toward the pressing direction. Then, by cutting, the individual pieces are completed, and the coil component 1 of the present embodiment is completed Figure 34 In addition, in order to reliably form the bent shape of the protruding portions 41A, 44A of the interlayer insulating films, the magnetic bodies M1 to M3 in a semi-cured state can be pressed, and after the pressing, the magnetic bodies M1 to M3 can be fully cured.

[0083] Thus, in the present embodiment, since the magnetic bodies M1 to M3 are pressed strongly in a manner that the protruding portions 41A, 44A that are parts of the interlayer insulating films 41, 44 are bent toward the inside, the entrance of the magnetic path in the inner diameter region can be widened compared to the case where the protruding portions 41A, 44A protrude linearly.

[0084] Further, in the present embodiment, since the interlayer insulating film 41 is laminated on the surface of the metal foil 63 provided with the protruding portion 63a, the shape of the protruding portion 63a is transferred to the interlayer insulating film 41. Thus, the region 41C where the film thickness is thick and the region 41D where the film thickness is thin are formed in the interlayer insulating film 41, and thus, the film thickness of the interlayer insulating film 41 can be made thinner by the ashing treatment shown in FIG. 8. Thus, the coil component 1 can be made low in height, and the protruding portion 41A can be bent more greatly. Figure 32 Thus, in the present embodiment, since the magnetic bodies M1 to M3 are pressed strongly in a manner that the protruding portions 41A, 44A that are parts of the interlayer insulating films 41, 44 are bent toward the inside, the entrance of the magnetic path in the inner diameter region can be widened compared to the case where the protruding portions 41A, 44A protrude linearly.

[0085] The above describes the preferred embodiments of the present application, but the present application is not limited to the above-described embodiments, and various modifications can be made within the scope of the present application, and these modifications are of course included in the scope of the present application.

[0086] Explanation of Reference Numerals

[0087] 1 Coil component

[0088] 10, 20, 30 Conductor layer

[0089] 11, 12, 21, 22, 31, 32 Electrode pattern

[0090] 41 to 44 Interlayer insulating film

[0091] 41A, 44A Protruding portion

[0092] 41B, 44B Corner portion

[0093] 41C Thick region

[0094] 41D Thin region

[0095] 42a Opening portion

[0096] 51-58...via conductors

[0097] 60...support

[0098] 61...substrate

[0099] 62-65...metal foil

[0100] 63a...protrusion

[0101] 70...support

[0102] C...coil portion

[0103] CP1-CP3...coil pattern

[0104] E1, E2...external terminal

[0105] M1-M3...magnetic body

[0106] R1-R4...resist pattern

[0107] S...space

[0108] S1-S4...seed layer

[0109] SL...slit

[0110] VP1-VP3...sacrificial pattern

Claims

1. A coil component characterized by comprising: a coil pattern wound spirally; a first interlayer insulating film covering the coil pattern from one side in an axial direction; a second interlayer insulating film covering the coil pattern from the other side in the axial direction; a magnetic body including a first portion embedded in an inner diameter region of the coil pattern, a second portion covering the coil pattern from the one side in the axial direction through the first interlayer insulating film, and a third portion covering the coil pattern from the other side in the axial direction through the second interlayer insulating film; and first and second external terminals connected to one end and the other end of the coil pattern, respectively, via openings provided in the second interlayer insulating film.

2. The coil component according to claim 1, characterized in that the second interlayer insulating film has a second protruding portion protruding radially toward the inner diameter region, and the second protruding portion is curved toward the one side in the axial direction.

3. The coil component according to claim 2, characterized in that the first protruding portion is curved more largely than the second protruding portion.

4. A coil component characterized by comprising: a coil pattern wound spirally; a first interlayer insulating film covering the coil pattern from one side in an axial direction; and a magnetic body including a first portion embedded in an inner diameter region of the coil pattern, and a second portion covering the coil pattern from the one side in the axial direction through the first interlayer insulating film, the first interlayer insulating film having a first protruding portion protruding radially toward the inner diameter region, the first protruding portion being curved toward the other side in the axial direction, the magnetic body being a composite member including a magnetic filler and a resin binder, and a protruding amount of the first protruding portion being smaller than a maximum diameter of the magnetic filler.

5. A method of manufacturing a coil component characterized by comprising: a first step of forming a coil pattern wound spirally and covered with an interlayer insulating film from one side in an axial direction; a second step of forming a protruding portion protruding radially toward an inner diameter region of the coil pattern in the interlayer insulating film; and a third step of embedding a magnetic body in the inner diameter region of the coil pattern and covering the coil pattern from the one side in the axial direction with the magnetic body through the interlayer insulating film, the first step including a step of forming the interlayer insulating film in a manner that a region having a thick film thickness and a region having a thin film thickness coincide with the inner diameter region of the coil pattern as viewed from the axial direction, the second step removing the region having the thin film thickness by reducing the film thickness of the interlayer insulating film as a whole, thereby forming the protruding portion, and in the third step, the magnetic body is pressed toward the other side in the axial direction in a manner that the protruding portion is curved toward the other side in the axial direction. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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