Coil component and method of manufacturing the same

A coil component includes a body and an external electrode. The body includes a coil conductor formed by winding a substantially rectangular wire covered with an insulating film, and a magnetic-body section containing a magnetic-body particle and a resin. The external electrode is electrically connected to an exposed surface of an extended portion of the coil conductor and is disposed at a surface of the body, the exposed surface being exposed at the surface of the body. The body includes first and second principal surfaces that face each other. At the wire, an average thickness of a portion of the insulating film that covers a first surface facing the first principal surface and extending in a direction orthogonal to a winding axis of the coil conductor is larger than average thicknesses of portions of the insulating film that cover other surfaces, orthogonal to the first surface, of the wire.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims benefit of priority to Japanese Patent Application No. 2020-059521, filed Mar. 30, 2020, the entire content of which is incorporated herein by reference.

BACKGROUND

Technical Field

The present disclosure relates to a coil component and a method of manufacturing the same.

Background Art

As a coil component known in the art, a winding-integrated-type coil in which an air-cored coil, such as a coil, is sealed with, for example, a magnetic mold material is disclosed (refer to, for example, Japanese Unexamined Patent Application Publication No. 2011-009618). Such a mold coil is acquired in the following way. That is, in a mold coil in which a wire is sealed with a mold resin, after rounding the corners of a molded item by utilizing the impact of powder accelerated by air, a coil terminal and an external electrode are joined to each other to acquire the mold coil. The mold resin contains magnetic powder.

In a coil component, such as that disclosed in Japanese Unexamined Patent Application Publication No. 2011-009618, since a molded body in which a wire is sealed with a mold resin containing magnetic powder is to be formed, when such a molded body is formed, the magnetic powder may become stuck in or may pierce through an insulating film of the wire. Therefore, a short circuit may occur in a coil conductor.

SUMMARY

Accordingly, the present disclosure provides a coil component that is made highly reliable by making it possible to suppress occurrence of a short circuit in a coil conductor when manufacturing the coil component.

According to preferred embodiments of the present disclosure, there is provided a coil component including a body that includes a coil conductor in which a substantially rectangular wire covered with an insulating film is wound, and a magnetic-body section that contains a metal magnetic-body particle and a resin; and including an external electrode that is electrically connected to an exposed surface of an extended portion of the coil conductor and that is disposed at a surface of the body. The exposed surface is exposed at the surface of the body. In the coil component, the body includes a first principal surface and a second principal surface that faces the first principal surface. At the substantially rectangular wire, an average thickness of a portion of the insulating film that covers a first surface facing the first principal surface and extending in a direction orthogonal to a winding axis of the coil conductor is larger than average thicknesses of portions of the insulating film that cover other surfaces of the substantially rectangular wire, the other surfaces being orthogonal to the first surface.

In the coil component according to preferred embodiments of the present disclosure, since the portion of the insulating film of the substantially rectangular wire that covers a surface which is pressed when manufacturing the coil component has a thickness that is larger than the thicknesses of the portions of the insulating film that cover the other surfaces, impact resistance is increased, as a result of which it is possible to suppress occurrence of short-circuit defects that may occur when the magnetic-body particle pierces through the insulating film. In such a coil component according to preferred embodiments of the present disclosure, since it is possible to increase the molding pressure in compression molding, it is possible to increase the ability to fill with the magnetic-body particle and to thus improve the efficiency with which inductance is obtained.

According to preferred embodiments of the present disclosure, it is possible to provide a coil component that is made highly reliable by making it possible to suppress occurrence of a short circuit in a coil conductor when manufacturing the coil component.

The aforementioned object, other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description of preferred embodiments of the present disclosure with reference to the attached drawings.

DETAILED DESCRIPTION

Coil components according to the present disclosure are described in detail below with reference to the drawings.

FIG.1is an external perspective view schematically illustrating a coil component according to a first embodiment of the present disclosure.FIG.2is a transparent, perspective view of a magnetic-body section having a coil conductor buried therein in the coil component shown inFIG.1.FIG.3is a sectional view along line inFIG.1.FIG.4is a sectional view along line IV-IV inFIG.1.FIG.5is an enlarged sectional view of a portion a inFIG.4.

A coil component10includes a substantially rectangular parallelepiped body12and external electrodes40.

The body12includes a magnetic-body section14and a coil conductor16that is buried in the magnetic-body section14. The body12includes a first principal surface12aand a second principal surface12bthat face each other in a pressing direction x, a first side surface12cand a second side surface12dthat face each other in a width direction y that is orthogonal to the pressing direction x, and a first end surface12eand a second end surface12fthat face each other in a length direction z that is orthogonal to the pressing direction x and the width direction y. The dimensions of the body12are not particularly limited to certain dimensions.

The magnetic-body section14contains magnetic-body particles and a resin material.

Although the resin material is not particularly limited to certain resin materials, examples thereof include thermosetting resins, such as organic materials including epoxy resin, phenol resin, polyester resin, polyimide resin, and polyolefin resin. Only one type of such substances above or two or more types of such substances above may be used for the resin material.

Although the magnetic-body particles desirably include first metal magnetic-body particles and second metal magnetic-body particles, the magnetic-body particles may include only the first metal magnetic-body particles.

The first metal magnetic-body particles have an average particle size of about 10 μm or greater. The average particle size of the first metal magnetic-body particles is, desirably, about 200 μm or less, more desirably, about 100 μm or less, and, even more desirably, about 80 μm or less. When the average particle size of the first metal magnetic-body particles is about 10 μm or greater, the magnetic properties of the magnetic-body section are improved.

The second metal magnetic-body particles have an average particle size that is smaller than the average particle size of the first metal magnetic-body particles. The second metal magnetic-body particles have an average particle size of about 5 μm or less. In this way, by causing the average particle size of the second metal magnetic-body particles to be smaller than the average particle size of the first metal magnetic-body particles, the ability with which the metal magnetic-body particles fill the magnetic-body section14is increased, as a result of which it is possible to improve the magnetic properties of the coil component10.

Here, the term “average particle size” refers to an average particle size D50 (a particle size equivalent to 50% in a volume-based cumulative percentage). The average particle size D50 can be measured with, for example, a dynamic light-scattering particle-size analyzer (manufactured by NIKKISO CO., LTD., UPA).

Although the first metal magnetic-body particles and the second metal magnetic-body particles are not particularly limited to certain particles, examples thereof include iron, cobalt, nickel, or cadmium, or an alloy of one type of such substances above or two or more types of such substances above. The first metal magnetic-body particles and the second metal magnetic-body particles are desirably iron particles or iron-alloy particles. Although the iron alloy is not particularly limited to certain iron alloys, examples thereof include Fe—Si, Fe—Si—Cr, Fe—Ni, and Fe—Si—Al. Only one type of such substances above or two or more types of such substances above may be used for the first metal magnetic-body particles and the second metal magnetic-body particles.

A surface of each first metal magnetic-body particle and a surface of each second metal magnetic-body particle may be covered with an insulating film. By covering the surface of each metal magnetic-body particle with an insulating film, it is possible to increase the internal resistance of the magnetic-body section14. Since the insulating properties of the surfaces of the metal magnetic-body particles are ensured by the insulating film, it is possible suppress short-circuit defects occurring with respect to the coil conductor16.

Note that the magnetic-body particles may be ferrite particles.

Examples of the material of the insulating film include silicon oxides, phosphate-based glass, and bismuth-based glass. In particular, it is desirable to use an insulating film formed from zinc-phosphate-based glass in which the metal magnetic-body particles are subjected to mechano-chemical treatment.

Although the thickness of the insulating film is not particularly limited to certain thicknesses, the thickness of the insulating film may be, desirably, about 5 nm or greater and about 500 nm or less (i.e., from about 5 nm to about 500 nm), more desirably, about 5 nm or greater and about 100 nm or less (i.e., from about 5 nm to about 100 nm), and, even more desirably, about 10 nm or greater and about 100 nm or less (i.e., from about 10 nm to about 100 nm). When the thickness of the insulating film is made large, it is possible to further increase the resistance of the magnetic-body section14. When the thickness of the insulating film is made small, it is possible to further increase the quantity of metal magnetic-body particles, as a result of which the magnetic properties of the magnetic-body section14are improved.

With respect to the entire magnetic-body section14, the quantity of first metal magnetic-body particles and the quantity of second metal magnetic-body particles contained in the magnetic-body section14are, desirably, about 50 vol % or greater, more desirably, about 60 vol % or greater, and, even more desirably, about 70 vol % or greater. By causing the quantity of first metal magnetic-body particles and second metal magnetic-body particles contained to be in such a range, the magnetic properties of the coil component of the present disclosure are improved. With respect to the entire magnetic-body section14, the quantity of first metal magnetic-body particles and the quantity of second metal magnetic-body particles contained are, desirably, about 99 vol % or less, more desirably, about 95 vol % or less, and, even more desirably, about 90 vol % or less. By causing the quantity of first metal magnetic-body particles and second metal magnetic-body particles contained to be in such a range, it is possible to further increase the resistance of the magnetic-body section14.

In a surface portion of the magnetic-body section14, a region that is adjacent to the coil conductor16may be removed. By removing the magnetic-body section14at the region adjacent to the coil conductor16, a gap between the magnetic-body section14and the coil conductor16is increased and media easily enters when barrel plating is performed, as a result of which a plating film is formed over a wider area of the coil conductor16. Therefore, an increase in joining strength and a reduction in electrical resistance are expected.

The coil conductor16includes a winding portion30that is formed by winding in the form of a coil a conductive belt body18, and a first extended portion32aand a second extended portion32b. The first extended portion32ais extended to one side of the winding portion30and the second extended portion32bis extended to the other side of the winding portion30. The coil conductor16is formed by winding the conductive belt body18into a substantially alpha shape. The winding portion30is wound into two layers.

The first extended portion32ais exposed from the first end surface12eof the body12to dispose a first exposed portion34a, and the second extended portion32bis exposed from the second end surface12fof the body12to dispose a second exposed portion34b.

As shown inFIGS.6to9, the conductive belt body18includes plate surfaces18aand plate surfaces18bthat face each other, and side end surfaces18cand side end surfaces18dthat face each other. In the conductive belt body18of the coil conductor16, the plate surfaces18aand the plate surfaces18bare orthogonal to the side end surfaces18cand the side end surfaces18d. The conductive belt body18includes a substantially linear rectangular wire20that is substantially rectangular in cross section, and an insulating film22that covers a surface of the substantially rectangular wire20.

In the conductive belt body18of the coil conductor16, the side end surfaces18cface the first principal surface12aof the body12, and the side end surfaces18dface the second principal surface12bof the body12.

As shown inFIGS.8and9, the coil conductor16includes a first principal surface16aof the coil conductor16that is formed from the plurality of side end surfaces18c, a second principal surface16bof the coil conductor16that is formed from the plurality of side end surfaces18d, a first side surface16cof the coil conductor16that is formed from the plurality of plate surfaces18a, and a second side surface16dof the coil conductor16that is formed from the plurality of plate surfaces18b.

The first principal surface16aof the coil conductor16faces the first principal surface12aof the body12, and the second principal surface16bof the coil conductor16faces the second principal surface12bof the body12.

The first side surface16cand the second side surface16dof the coil conductor16are orthogonal to the first principal surface16aand the second principal surface16bof the coil conductor16.

As shown inFIG.2, the winding portion30of the coil conductor16is wound around a winding axis O as a center. The coil conductor16is wound so that the plate surfaces18aand the plate surfaces18boverlap each other with the plate surfaces18aand the plate surfaces18bof the conductive belt body18being substantially parallel to the winding axis O and the side end surfaces18cand the side end surfaces18dof the conductive belt body18being substantially perpendicular to the winding axis O. Note that, inFIG.2, the coil conductor16may be wound in a substantially oval form, in a substantially elliptical form, or in a circular form.

For example, the width of the substantially rectangular wire20at the plate surfaces18aand18bis about 15 μm or greater and about 200 μm or less (i.e., from about 15 μm to about 200 μm), and the width of the substantially rectangular wire20at the side end surfaces18cand18dis about 50 μm or greater and about 500 μm or less (i.e., from about 50 μm to about 500 μm).

The substantially rectangular wire20of the conductive belt body18is formed from, for example, a metal wire or a wire. Although the conductive material of the substantially rectangular wire20is not particularly limited to certain conductive materials, examples thereof include metal components including Ag, Au, Cu, Ni, Sn, and an alloy thereof. As the conductive material, copper is desirably used. As the conductive material, only one type of such substances above or two or more types of such substances above may be used.

A surface of the substantially rectangular wire20is covered with an insulating substance to form the insulating film22. By covering the substantially rectangular wire20with an insulating substance, it is possible to more reliably insulate portions of the wound conductive belt body18from each other and more reliably insulate the conductive belt body18and the magnetic-body section14from each other.

Note that the insulating film22is not formed at a portion of each of the first exposed portion34aand the second exposed portion34bof the conductive belt body18that forms the coil conductor16. Therefore, the external electrodes40are easily formed by plating. In addition, it is possible to further reduce the resistance at an electrical connection between the coil conductor16and the external electrodes40.

Although the insulating substance of the insulating film22is not particularly limited to certain insulating substances, the insulating substance is at least one type selected from, for example, polyimide resin, polyamide resin, polyurethane resin, polyamide-imide resin, polyester resin, and enamel resin.

As shown inFIG.6, at the substantially rectangular wire20, an average thickness ta1of a portion of the insulating film22that covers each side end surface18cfacing the first principal surface12aand extending in a direction orthogonal to the winding axis O of the coil conductor16is larger than average thicknesses of portions of the insulating film22that cover the other surfaces of the substantially rectangular wire20, that is, an average thickness tc1of portions of the insulating film22that cover the plate surfaces18aand the plate surfaces18b, and an average thickness tb1of a portion of the insulating film22that covers the side end surfaces18d. Here, the relationship between the average thicknesses of the portions of the insulating film22satisfies ta1>tb1≥tc1. The average thickness ta1of the insulating film22is desirably about 4 μm or greater and about 20 μm or less (i.e., from about 4 μm to about 20 μm), and the average thickness tb1of the insulating film22and the average thickness tc1of the insulating film22are desirably about 1 μm or greater and about 10 μm or less (i.e., from about 1 μm to about 10 μm). Here, when the particle size of the average particle size D50 of the second metal magnetic-body particles is D, it is desirable that the average thickness tai of the insulating film22satisfy the relationship of D<ta1.

As shown inFIG.7, at the substantially rectangular wire20, the average thickness ta1of the portion of the insulating film22that covers the side end surfaces18cfacing the first principal surface12aand extending in the direction orthogonal to the winding axis O of the coil conductor16and the average thickness tb1of the portion of the insulating film22that covers the side end surfaces18dfacing the second principal surface12band extending in the direction orthogonal to the winding axis O of the coil conductor16are greater than the average thickness of the portions of the insulating film22that cover the other surfaces of the substantially rectangular wire20, that is, the average thickness tc1of the portions of the insulating film22that cover the plate surfaces18aand the plate surfaces18b. Here, the relationship between the average thicknesses of the portions of the insulating film22desirably satisfies ta1=tb1>tc1. The average thickness ta1of the insulating film22and the average thickness tb1of the insulating film22are desirably about 4 μm or greater and about 20 μm or less (i.e., from about 4 μm to about 20 μm), and the average thickness tc1of the insulating film22is desirably about 1 μm or greater and about 10 μm or less (i.e., from about 1 μm to about 10 μm). When the particle size of the average particle size D50 of the second metal magnetic-body particles is D, the average thickness ta1and the average thickness tb1of the insulating film22desirably satisfy the relationship of D<ta1and the relationship D<tb1.

As shown inFIG.8, the first principal surface16aand the second principal surface16bof the coil conductor16may be covered with a coil insulating film24.

At the coil conductor16, an average thickness tAof a portion of the coil insulating film24that covers the first principal surface16aof the coil conductor16facing the first principal surface12aand extending in a direction orthogonal to the winding axis O of the coil conductor16and an average thickness tBof a portion of the coil insulating film24that covers the second principal surface16bof the coil conductor16facing the second principal surface12band extending in the direction orthogonal to the winding axis O of the coil conductor16are desirably about 1 μm or greater and about 20 μm or less (i.e., from about 1 μm to about 20 μm). In this case, the average thickness of the insulating film22that covers the substantially rectangular wire20may be a substantially uniform thickness. Therefore, an average thickness tA+ta1of a portion of the insulating film that forms the first principal surface16aof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16and an average thickness tB+tb1of a portion of the insulating film that forms the second principal surface16bof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16are larger than the average thickness of the portions of the insulating film that cover the first side surface16cand the second side surface16dof the coil conductor16(that is, the average thickness tc1of the portions of the insulating film that cover the plate surfaces18aand the plate surfaces18bof the substantially rectangular wire20). The average thickness tA+ta1of the portion of the insulating film that forms the first principal surface16aof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16and the average thickness tB+tb1of the portion of the insulating film that forms the second principal surface16bof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16are about 5 μm or greater and about 40 μm or less (i.e., from about 5 μm to about 40 μm).

Further, as shown inFIG.9, the first principal surface16aand the second principal surface16bof the coil conductor16, and the first side surface16cand the second side surface16dof the coil conductor16may be covered with the coil insulating film24.

The average thickness tAof the portion of the coil insulating film24that covers the first principal surface16aof the coil conductor16facing the first principal surface12aand extending in the direction orthogonal to the winding axis O of the coil conductor16and the average thickness tBof the portion of the coil insulating film24that covers the second principal surface16bof the coil conductor16facing the second principal surface12band extending in the direction orthogonal to the winding axis O of the coil conductor16are desirably larger than the average thickness of a portion of the coil insulating film24that covers the other surface of the coil conductor16, that is, an average thickness tCof the portions of the coil insulating film24that cover the first side surface16cand the second side surface16dof the coil conductor16. In this case, the average thickness of the insulating film22that covers the substantially rectangular wire20may be a substantially uniform thickness. Therefore, the average thickness tA+ta1of the portion of the insulating film that forms the first principal surface16aof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16and the average thickness tB+tb1of the portion of the insulating film that forms the second principal surface16bof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16are larger than an average thickness tC+tc1of the portions of the insulating film that form the first side surface16cand the second side surface16dof the coil conductor16. The average thickness tA+ta1of the portion of the insulating film that forms the first principal surface16aof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16and the average thickness tB+tb1of the portion of the insulating film that forms the second principal surface16bof the coil conductor16extending in the direction orthogonal to the winding axis O of the coil conductor16are about 5 μm or greater and about 40 μm or less (i.e., from about 5 μm to about 40 μm).

The insulating film22may have two or more layers. In particular, the portion of the insulating film22that covers the side end surfaces18cfacing the first principal surface12aand extending in the direction orthogonal to the winding axis O of the coil conductor16desirably has two or more layers.

In addition, at the substantially rectangular wire20, the portion of the insulating film22that covers the side end surfaces18cfacing the first principal surface12aand extending in the direction orthogonal to the winding axis O of the coil conductor16and the portion of the insulating film22that covers the side end surfaces18dfacing the second principal surface12band extending in the direction orthogonal to the winding axis O of the coil conductor16desirably have two or more layers.

This makes it possible to make it less likely for the magnetic-body particles to pierce through the insulating film22. By forming the portions of the insulating film22having two or more layers with different compositions, it is possible to improve the insulating properties of the coil conductor16, increase the mechanical strength of the coil conductor16, and increase the ability to join the portions of the substantially rectangular wire20to each other.

Further, at the insulating film22having two or more layers, an outer layer is desirably covered with a thermal adhesion layer, which is a layer having thermal adhesiveness. Therefore, when the conductive belt body18is wound, the portions of the conductive belt body18are joined to each other, and thus it is possible to increase the joining strength between the portions of the conductive belt body18and to increase the ability to maintain the shape of the coil conductor16.

It is desirable that the insulating film22not be disposed at exposed portions (exposed surfaces) at the end surfaces12eand12fof the body12, where the first exposed portion34aand the second exposed portion34bare respectively disposed at the conductive belt body18of the coil conductor16. Therefore, the coil conductor16and the external electrodes40can be directly electrically connected to each other, and thus it is possible to reduce electrical resistance between the coil conductor16and each external electrode40.

Further, at the metal magnetic-body particles that are in contact with the external electrodes40, the average thickness of the insulating film that is in contact with the external electrodes40is desirably smaller than the average thickness of the insulating film that is not in contact with the external electrodes40. Therefore, when the external electrodes40are formed by plating, it is possible to pass current in a concentrated manner through the metal magnetic-body particles that are positioned near the first extended portion32aand the second extended portion32bof the coil conductor16, which are respectively exposed at the first end surface12eand the second end surface12fof the body12, and to further perform the film plating.

The external electrodes40are each disposed on a corresponding one of a side of the first end surface12eand a side of the second end surface12fof the body12. The external electrodes40include a first external electrode40aand a second external electrode40b.

The first external electrode40ais disposed on the first end surface12eof the body12. Note that the first external electrode40amay be formed so as to extend from the first end surface12eand cover a part of the first principal surface12a, a part of the second principal surface12b, a part of the first side surface12c, and a part of the second side surface12d, or may be formed so as to extend from the first end surface12eto the second principal surface12band cover a part of the first end surface12eand a part of the second principal surface12b. In this case, the first external electrode40ais electrically connected to the first extended portion32aof the coil conductor16.

The second external electrode40bis disposed on the second end surface12fof the body12. Note that the second external electrode40bmay be formed so as to extend from the second end surface12fand cover a part of the first principal surface12a, a part of the second principal surface12b, a part of the first side surface12c, and a part of the second side surface12d, or may be formed so as to extend from the second end surface12fto the second principal surface12band cover a part of the second end surface12fand a part of the second principal surface12b. In this case, the second external electrode40bis electrically connected to the second extended portion32bof the coil conductor16.

Although the thickness of the first external electrode40aand the thickness of the second external electrode40bare not particularly limited to certain thicknesses, the thickness of the first external electrode40aand the thickness of the second external electrode40bmay be, for example, about 1 μm or greater and about 50 μm or less (i.e., from about 1 μm to about 50 μm) and desirably about 5 μm or greater and about 20 μm or less (i.e., from about 5 μm to about 20 μm).

The first external electrode40aincludes a first underlying electrode layer42aand a first plating layer44athat is disposed on a surface of the first underlying electrode layer42a. Similarly, the second external electrode40bincludes a second underlying electrode layer42band a second plating layer44bthat is disposed on a surface of the second underlying electrode layer42b.

The first underlying electrode layer42ais disposed on the first end surface12eof the body12. Therefore, the first underlying electrode layer42ais directly in contact with the first exposed portion34aof the coil conductor16. Note that the first underlying electrode layer42amay be formed so as to extend from the first end surface12eand cover a part of the first principal surface12a, a part of the second principal surface12b, a part of the first side surface12c, and a part of the second side surface12d, or may be formed so as to extend from the first end surface12eand cover a part of the first end surface12eand a part of the second principal surface12b.

The second underlying electrode layer42bis disposed on the second end surface12fof the body12. Therefore, the second underlying electrode layer42bis directly in contact with the second exposed portion34bof the coil conductor16. Note that the second underlying electrode layer42bmay be formed so as to extend from the second end surface12fand cover a part of the first principal surface12a, a part of the second principal surface12b, a part of the first side surface12c, and a part of the second side surface12d, or may be formed so as to extend from the second end surface12fand cover a part of the second end surface12fand a part of the second principal surface12b.

The first underlying electrode layer42aand the second underlying electrode layer42bare made of a conductive material, desirably, one or more types of metal materials selected from Au, Ag, Pd, Ni, and Cu. The first underlying electrode layer42aand the second underlying electrode layer42bare each formed as a plating electrode. The first underlying electrode layer42aand the second underlying electrode layer42bmay be formed by electrolytic plating or electroless plating.

The compositions of the main components of the metal materials constituting the first underlying electrode layer42aand the second underlying electrode layer42bare desirably the same as the composition of the main components of the metal material constituting the coil conductor16.

The average thickness of the first underlying electrode layer42aand the average thickness of the second underlying electrode layer42bare, for example, about 10 μm.

The first plating layer44ais disposed so as to cover the first underlying electrode layer42a. Specifically, the first plating layer44amay be disposed so as to cover the first underlying electrode layer42athat is disposed on the first end surface12eand may further be disposed so as to extend from the first end surface12eand cover a surface of the first underlying electrode layer42a, at which the first principal surface12a, the second principal surface12b, the first side surface12c, and the second side surface12dare disposed, or may be disposed so as to cover the first underlying electrode layer42athat is disposed so as to extend from the first end surface12eand cover a part of the first end surface12eand a part of the second principal surface12b.

The second plating layer44bis disposed so as to cover the second underlying electrode layer42b. Specifically, the second plating layer44bmay be disposed so as to cover the second underlying electrode layer42bthat is disposed on the second end surface12fand may further be disposed so as to extend from the second end surface12fand cover a surface of the second underlying electrode layer42b, at which the first principal surface12a, the second principal surface12b, the first side surface12c, and the second side surface12dare disposed, or may further be disposed so as to cover the second underlying electrode layer42bthat is disposed so as to extend from the second end surface12fand cover a part of the second end surface12fand a part of the second principal surface12b.

As metal materials of the first plating layer44aand the second plating layer44b, for example, at least one substance is selected from Cu, Ni, Ag, Sn, Pd, a Ag—Pd alloy, and Au.

The first plating layer44aand the second plating layer44bmay each have a plurality of layers.

The first plating layer44ahas a two-layer structure including a first Ni plating layer46aand a first Sn plating layer48athat is formed on a surface of the first Ni plating layer46a. The second plating layer44bhas a two-layer structure including a second Ni plating layer46band a second Sn plating layer48bthat is formed on a surface of the second Ni plating layer46b.

The average thickness of the first Ni plating layer46aand the average thickness of the second Ni plating layer46bare, for example, about 5 μm.

The average thickness of the first Sn plating layer48aand the average thickness of the second Sn plating layer48bare, for example, about 10 μm.

Note that the first external electrode40aand the second external electrode40bmay be provided with a structure such as that described below.

For example, the first underlying electrode layer42aand the second underlying electrode layer42bmay each be a resin electrode containing Ag, and may include an Ag sputter layer, a Cu sputter layer, or a Ti sputter layer, which are formed by sputtering. Note that when the first underlying electrode layer42aand the second underlying electrode layer42bare each a resin electrode containing Ag, they may each contain a glass frit. When the first underlying electrode layer42aand the second underlying electrode layer42bare formed by sputtering, the Cu sputter layer may be formed on the Ti sputter layer.

The first plating layer44aand the second plating layer44bmay be such that their outermost layers are constituted by only the Sn plating layer48aand the Sn plating layer48b, respectively.

Further, an Ag plating layer or a Ni plating layer may be formed on the body12without forming the first underlying electrode layer42aand the second underlying electrode layer42b.

In the embodiment, a protective layer50is provided on a surface of the body12excluding a portion where the first exposed portion34ais exposed at the first end surface12eof the body12and a portion where the second exposed portion34bis exposed at the second end surface12fof the body12. The protective layer50is made of, for example, a resin material having a high electrical insulation performance, such as acrylic resin, epoxy resin, phenol resin, or polyimide resin. Note that, although in the present disclosure, the protective layer50is provided, the protective layer50need not be provided.

When a dimension in the length direction z of the coil component10is a dimension L, the dimension L is desirably about 1.0 mm or greater and about 12.0 mm or less (i.e., from about 1.0 mm to about 12.0 mm). When a dimension in the width direction y of the coil component10is a dimension W, the dimension W is desirably about 0.5 mm or greater and about 12.0 mm or less (i.e., from about 0.5 mm to about 12.0 mm). When a dimension in the pressing direction x of the coil component10is a dimension T, the dimension T is about 0.5 mm or greater and about 6.0 mm or less (i.e., from about 0.5 mm to about 6.0 mm).

At the substantially rectangular wire20, since the average thickness ta1of the portion of the insulating film22that covers the side end surfaces18cfacing the first principal surface12aand extending in the direction orthogonal to the winding axis O of the coil conductor16is larger than the average thicknesses of the portions of the insulating film22that cover the other surfaces of the substantially rectangular wire20, that is, the average thickness tc1of the portions of the insulating film22that covers the plate surfaces18aand the plate surfaces18b, and the average thickness tb1of the portion of the insulating film22that covers the side end surface18d, the coil component10shown inFIG.1has increased impact resistance, and thus is capable of suppressing occurrence of short-circuit defects that occur when magnetic-body particles pierce through the insulating film22. In such a coil component according to the present disclosure, since it is possible to increase the molding pressure in compression molding, it is possible to increase the ability to fill with the magnetic-body particles and to thus improve the efficiency with which inductance is obtained.

Compared with when the insulating film22on the entire substantially rectangular wire20is thick, it is possible to reduce the volume of the magnetic-body section14and to suppress a reduction in magnetic permeability.

Next, a coil component110according to a second embodiment of the present disclosure is described.

FIG.10is an external perspective view schematically illustrating the coil component according to the second embodiment of the present disclosure.FIG.11is a transparent, perspective view of a magnetic-body section having a coil conductor buried therein in the coil component shown inFIG.10.FIG.12is a sectional view along line XII-XII inFIG.10.FIG.13is a sectional view along line XIII-XIII inFIG.10.FIG.14is an enlarged sectional view of a portion e inFIG.13.

A body112includes a magnetic-body section114and a coil conductor116that is buried in the magnetic-body section114. The body112includes a first principal surface112aand a second principal surface112bthat face each other in a height direction x, a first side surface112cand a second side surface112dthat face each other in the width direction y that is orthogonal to the height direction x, and a first end surface112eand a second end surface112fthat face each other in the length direction z that is orthogonal to the height direction x and the width direction y.

The coil conductor116includes a winding portion130that is formed by winding in the form of a coil a conductive belt body118, which is one type of coil wire rod, and a first extended portion132aand a second extended portion132b. The first extended portion132ais extended to one side of the winding portion130and the second extended portion132bis extended to the other side of the winding portion130. The coil conductor116is formed by winding the conductive belt body118into a substantially alpha shape. The conductive belt body118is wound in the form of an edgewise coil.

The first extended portion132ais exposed from the first end surface112eof the body112to dispose a first exposed portion134a, and the second extended portion132bis exposed from the second end surface112fof the body112to dispose a second exposed portion134b.

The conductive belt body118includes plate surfaces118aand plate surfaces118bthat face each other, and side end surfaces118cand side end surfaces118dthat face each other. The conductive belt body118includes a substantially linear rectangular wire120that is substantially rectangular in cross section, and an insulating film122that covers a surface of the substantially rectangular wire120.

In the conductive belt body118of the coil conductor116, the plate surfaces118aface the first principal surface112aof the body112, and the plate surfaces118bface the second principal surface112bof the body112.

As shown inFIG.14, the coil conductor116includes a first principal surface116aof the coil conductor116that is formed from the plate surfaces118a, a second principal surface116bof the coil conductor116that is formed from the plate surfaces118b, a first side surface116cof the coil conductor116that is formed from the plurality of side end surfaces118c, and a second side surface116dof the coil conductor116that is formed from the plurality of side end surfaces118d.

The first principal surface116aof the coil conductor116faces the first principal surface112aof the body112, and the second principal surface116bof the coil conductor116faces the second principal surface112bof the body112.

As shown inFIG.11, the winding portion130of the coil conductor116is wound around a winding axis O as a center. The coil conductor116is wound so that the plate surfaces118aand the plate surfaces118boverlap each other with the plate surfaces118aand the plate surfaces118bof the conductive belt body118being substantially perpendicular to the winding axis O and the side end surfaces118cand the side end surfaces118dof the conductive belt body118being substantially parallel to the winding axis O. Note that, although, inFIG.11, the coil conductor116is wound in a substantially elliptical form, the coil conductor116may be wound in a circular form.

For example, the width of the substantially rectangular wire120at the side end surfaces118cand the side end surfaces118dis about 15 μm or greater and about 200 μm or less (i.e., from about 15 μm to about 200 μm), and the width of the substantially rectangular wire120at the plate surfaces118aand118bis about 50 μm or greater and about 500 μm or less (i.e., from about 50 μm to about 500 μm).

The substantially rectangular wire120of the conductive belt body118is formed from, for example, a metal wire or a wire. Although the conductive material of the substantially rectangular wire120is not particularly limited to certain conductive materials, examples thereof include metal components including Ag, Au, Cu, Ni, Sn, and an alloy thereof. As the conductive material, copper is desirably used. As the conductive material, only one type of such substances above or two or more types of such substances above may be used.

A surface of the substantially rectangular wire120is covered with an insulating substance to form the insulating film122. By covering the substantially rectangular wire120with an insulating substance, it is possible to more reliably insulate portions of the wound conductive belt body118from each other and more reliably insulate the conductive belt body118and the magnetic-body section114from each other.

Note that the insulating film122is not formed at a portion of each of the first exposed portion134aand the second exposed portion134bof the conductive belt body118that forms the coil conductor116. Therefore, external electrodes140are easily formed by plating. In addition, it is possible to further reduce the resistance at an electrical connection between the coil conductor116and the external electrodes140.

Although the insulating substance of the insulating film122is not particularly limited to certain insulating substances, the insulating substance is at least one type selected from, for example, polyimide resin, polyamide resin, polyurethane resin, polyamide-imide resin, polyester resin, and enamel resin.

As shown inFIG.15, at the substantially rectangular wire120, an average thickness ta2of a portion of the insulating film122that covers the plate surfaces118afacing the first principal surface112aand extending in a direction orthogonal to the winding axis O of the coil conductor116is larger than an average thickness tb2of a portion of the insulating film122that covers the plate surfaces118bfacing the second principal surface112band extending in the direction orthogonal to the winding axis O of the coil conductor116. Here, the relationship between the average thicknesses of the portions of the insulating film122satisfies ta2>tb2≥tc2. The average thickness ta2of the insulating film122is desirably about 4 μm or greater and 20 μm or less (i.e., from about 4 μm to 20 μm), and the average thickness tb2of the insulating film122and the average thickness tc2of the insulating film122are desirably about 1 μm or greater and 10 μm or less (i.e., from about 1 μm to 10 μm). Here, when the particle size of the average particle size D50 of second metal magnetic-body particles is D, the average thickness ta2of the insulating film122desirably satisfy the relationship of D<ta2.

As shown inFIG.16, at the substantially rectangular wire120, the average thickness ta2of the portion of the insulating film122that covers the plate surfaces118afacing the first principal surface112aand extending in the direction orthogonal to the winding axis O of the coil conductor116and the average thickness tb2of the portion of the insulating film122that covers the plate surfaces118bfacing the second principal surface112band extending in the direction orthogonal to the winding axis O of the coil conductor116are desirably larger than the average thickness of portions of the insulating film122that cover the other surfaces of the substantially rectangular wire120, that is, the average thickness tc2of the portions of the insulating film122that cover the side end surfaces118cand the side end surfaces118d. Here, the relationship between the average thicknesses of the portions of the insulating film122desirably satisfies ta2=tb2>tc2. The average thickness ta2of the insulating film122and the average thickness tb2of the insulating film122are desirably about 4 μm or greater and about 20 μm or less (i.e., from about 4 μm to about 20 μm), and the average thickness tc2of the insulating film122is desirably about 1 μm or greater and about 10 μm or less (i.e., from about 1 μm to about 10 μm). When the particle size of the average particle size D50 of the second metal magnetic-body particles is D, it is desirable that the average thickness ta2of the insulating film122and the average thickness tb2of the insulating film122desirably satisfy the relationship of D<ta2and the relationship D<tb2, respectively.

The insulating film122may have two or more layers. In particular, the portion of the insulating film122that covers the plate surfaces118afacing the first principal surface112aand extending in the direction orthogonal to the winding axis O of the coil conductor116desirably has two or more layers.

In addition, at the substantially rectangular wire120, the portion of the insulating film122that covers the plate surfaces118afacing the first principal surface112aand extending in the direction orthogonal to the winding axis O of the coil conductor116and the portion of the insulating film122that covers the plate surfaces118bfacing the second principal surface112band extending in the direction orthogonal to the winding axis O of the coil conductor116desirably have two or more layers.

Further, at the insulating film122having two or more layers, an outer layer is desirably covered with a thermal adhesion layer, which is a layer having thermal adhesiveness. Therefore, when the conductive belt body118is wound, the portions of the conductive belt body118are joined to each other, and thus it is possible to increase the joining strength between the portions of the conductive belt body118and to increase the ability to maintain the shape of the coil conductor116.

When, as shown inFIG.12, the first extended portion132aof the coil conductor116is exposed from the first principal surface112a, a first external electrode140ais formed so as to cover a part of the first principal surface112a. In this case, the first external electrode140ais electrically connected to the first extended portion132aof the coil conductor116.

When, as shown inFIG.12, the second extended portion132bof the coil conductor116is exposed from the first principal surface112a, a second external electrode140bis formed so as to cover a part of the first principal surface112a. In this case, the second external electrode140bis electrically connected to the second extended portion132bof the coil conductor116.

The first external electrode140aincludes a first underlying electrode layer142aand a first plating layer144athat is disposed on a surface of the first underlying electrode layer142a. Similarly, the second external electrode140bincludes a second underlying electrode layer142band a second plating layer144bthat is disposed on a surface of the second underlying electrode layer142b.

As shown inFIG.12, when the coil conductor116is such that the first extended portion132aof the coil conductor116is exposed from the first principal surface112a, the first underlying electrode layer142ais formed on a part of the first principal surface112aso as to cover the first extended portion132aof the coil conductor116.

As shown inFIG.12, when the second extended portion132bof the coil conductor116is exposed from the first principal surface112a, the second underlying electrode layer142bis formed on a part of the first principal surface112aso as to cover the second extended portion132bof the coil conductor116.

Here, the first underlying electrode layer142aand the second underlying electrode layer142bare formed from a plurality of crystal particles. The particle size of the crystal particles of the first underlying electrode layer142aand the second underlying electrode layer142bis desirably about 100 nm or greater and about 2000 nm or less (i.e., from about 100 nm to about 2000 nm).

As shown inFIG.12, when the first extended portion132aof the coil conductor116is exposed from the first principal surface112a, the first plating layer144ais formed so as to cover the first underlying electrode layer142athat is disposed on the first principal surface112a.

As shown inFIG.12, when the second extended portion132bof the coil conductor116is exposed from the first principal surface112a, the second plating layer144bis formed so as to cover the second underlying electrode layer142bthat is disposed on the first principal surface112a.

The first plating layer144aand the second plating layer144bmay each have a plurality of layers.

The first plating layer144ahas a two-layer structure including a first Ni plating layer146aand a first Sn plating layer148athat is formed on a surface of the first Ni plating layer146a. The second plating layer144bhas a two-layer structure including a second Ni plating layer146band a second Sn plating layer148bthat is formed on a surface of the second Ni plating layer146b.

The average thickness of the first Ni plating layer146aand the average thickness of the second Ni plating layer146bare, for example, about 5 μm.

The average thickness of the first Sn plating layer148aand the average thickness of the second Sn plating layer148bare, for example, about 10 μm.

The coil component110shown inFIG.10provides the same effects as those provided by the coil component10shown inFIG.1.

2. Method of Manufacturing Coil Component

Next, a method of manufacturing a coil component is described.

(A) Preparation of Metal Magnetic-Body Particles

First, metal magnetic-body particles are prepared. Here, the metal magnetic-body particles are not particularly limited to certain particles, and may be, for example, a soft-magnetic-material powder based on Fe, such as α-Fe, Fe—Si, Fe—Si—Cr, Fe—Si—Al, Fe—Ni, or Fe—Co. The material form of the metal magnetic-body particles is desirably an amorphous material having good soft magnetic properties, but is not particularly limited to certain material forms, and may be a crystalline material.

Although the average particle size of the metal magnetic-body particles is not particularly limited to certain average particle sizes, it is desirable to use metal magnetic-body particles having two or more different average particle sizes. That is, the metal magnetic-body particles are dispersed in a resin material. Therefore, from the viewpoint of increasing the filling efficiency of the metal magnetic-body particles, it is desirable to use metal magnetic-body particles having different average particle sizes, such as first metal magnetic-body particles having an average particle size of about 10 μm or greater and about 40 μm or less (i.e., from about 10 μm to about 40 μm) and second metal magnetic-body particles having an average particle size of about 1 μm or greater and about 20 μm or less (i.e., from about 1 μm to about 20 μm).

(B) Formation of Insulating Film

Next, the surfaces of the metal magnetic-body particles are covered with an insulating film. Here, when the insulating film is to be formed by a mechanical method, it is possible to put the metal magnetic-body particles and an insulating-material powder into a rotating container, combine the particles by mechano-chemical treatment, and thereby cover the surfaces of magnetic-body powder with the insulating film.

(C) Fabrication of Magnetic-Body Sheet

Next, the resin material is prepared. The resin material is not particularly limited to certain resin materials, and can be, for example, epoxy resin, phenol resin, polyester resin, polyimide resin, or a polyolefin resin.

Next, the metal magnetic-body particles covered with the insulating film and a filler component (a glass material, ceramic powder, ferrite powder, or the like) is mixed with the resin material into the form of a slurry. Next, the slurry is formed by, for example, a doctor blade method and is then dried, to thereby fabricate a magnetic-body sheet having the filler component dispersed in the resin material and having a thickness of about 50 μm or greater and about 300 μm or less (i.e., from about 50 μm to about 300 μm).

(D) Preparation of Coil Conductor

Next, with Cu as a wire conductor, the coil conductor16that is formed by winding into a substantially alpha shape the conductive belt body18including the substantially rectangular wire20covered with the insulating film22is prepared.

The conductive belt body18includes the substantially linear rectangular wire20that is substantially rectangular in cross section, and the insulating film22that covers the surface of the substantially rectangular wire20. The conductive belt body18includes the plate surfaces18aand the plate surfaces18bthat face each other, and the side end surfaces18cand the side end surfaces18dthat face each other. In the conductive belt body18of the coil conductor16, the plate surfaces18aand the plate surfaces18bare orthogonal to the side end surfaces18cand the side end surfaces18d. In order to acquire the conductive belt body18, first, the entire surface of the substantially rectangular wire20is substantially uniformly coated with the insulating film22. Next, only the side end surfaces18cof the conductive belt body18are further coated with the insulating film22to acquire the conductive belt body18as that as shown inFIG.6. Note that only both the side end surfaces18cand the side end surfaces18dmay be further coated with the insulating film22. Therefore, the conductive belt body18as that shown inFIG.7is acquired. The substantially rectangular wire20may be coated with the insulating film22by, for example, dipping.

In order to acquire the conductive belt body18, first, the entire surface of the substantially rectangular wire20may be substantially uniformly coated with the insulating film22. Then, the conductive belt body18may be wound into a substantially alpha shape and then the first principal surface16aand the second principal surface16bof the coil conductor16may be coated with the coil insulating film24, as a result of which it is possible to acquire the coil conductor16as that shown inFIG.8A.

Further, in order to acquire the conductive belt body18, first, the entire surface of the substantially rectangular wire20may be substantially uniformly coated with the insulating film22. Then, the conductive belt body18may be wound into a substantially alpha shape and then the first principal surface16aand the second principal surface16bof the coil conductor16and the first side surface16cand the second side surface16dof the coil conductor16may be substantially uniformly coated with the coil insulating film24. Then, only the first principal surface16aand the second principal surface16bof the coil conductor16may be further coated with the coil insulating film24, as a result of which it is possible to acquire the coil conductor16as that shown inFIG.9.

Note that the first side surface16cand the second side surface16dof the coil conductor16are orthogonal to the first principal surface16aand the second principal surface16bof the coil conductor16.

(E) Fabrication of Collective Base

Next, if necessary, the insulating film22at a region that is about 50 μm from an end of the coil conductor16is removed by nipper-like scissors. Therefore, although not shown, an insulating film removal portion, which is a portion that is not covered in a substantially annular shape with the insulating film22with an extension direction of the coil conductor16being a center axis, is formed. Note that the insulating film22can be removed by burning off the region as a result of heating it, or by dissolving the region with a chemical liquid or laser.

Next, the body12having the coil conductor16buried therein is manufactured.

FIGS.17A to17Dis a manufacturing process diagram of an embodiment of manufacturing a first molded body in the method of manufacturing the coil component.FIGS.18A to18Dis a manufacturing process diagram of an embodiment of manufacturing the collective base in the method of manufacturing the coil component.

First, as shown inFIG.17A, a first die60is prepared, and coil conductors16are disposed in a matrix on the first die60.

Next, as shown inFIG.17B, a first magnetic-body sheet70aincluding a mixture of the first metal magnetic-body particles, the second metal magnetic-body particles, and the resin material is superimposed upon the coil conductors16, and, then, as shown in FIG.17C, a second die62is disposed on a side of an upper surface of the first magnetic-body sheet70a. Then, as shown inFIG.17D, the first magnetic-body sheet70ais sandwiched between the coil conductors16on the first die60and the second die62, and is subjected to primary press-molding in a direction of the winding axis O. Due to the primary press-molding, at least a part of the coil conductors16is buried in the sheet, the inside of such coil conductors16is filled with the mixture, as a result of which a first molded body72is fabricated.

Next, as shown inFIG.18A, the first molded body72in which the coil conductors16acquired by the primary press-molding are buried is separated from the second die62, is turned upside down, and is disposed on the first die60. Then, a different second magnetic-body sheet70bis superimposed upon a surface at which the coil conductors16are exposed. Next, as shown inFIG.18B, a third die64is disposed on a side of an upper surface of the second magnetic-body sheet70b. Then, as shown inFIG.18C, the second magnetic-body sheet70bis sandwiched between the first molded body72on the first die60and the third die64to perform a secondary pressing operation in the direction of the winding axis O.

Next, after the secondary pressing operation, as shown inFIG.18D, the third die64is separated, as a result of which the collective base (second molded body)74in which all of the coil conductors16are buried in the first magnetic-body sheet70aand the second magnetic-body sheet70bis fabricated.

(F) Fabrication of Body

Next, the first die60and the third die64are separated, and, as shown inFIG.18D, after fabricating the collective base74, a cutting tool, such as a dicer, is used to cut the collective base74along a cutting line into individual pieces, as a result of which the body12in which the coil conductor16is buried therein so that the first exposed portion34aand the second exposed portion34bof the coil conductor16are exposed from the respective end surfaces of the body12is fabricated. The collective base74can divided into each body12with a dicing blade, various laser devices, a dicer, various cutting tools, or a die. In a desirable mode, a cut surface of each body12is subjected to barrel grinding.

Next, the protective layer50is formed on the entire surface of the body acquired above. It is possible to form the protective layer50by, for example, electrodeposition, a spray method, or a dip method.

By irradiating with laser the vicinity of a location at which the first exposed portion34aand the second exposed portion34bof the coil conductor16of the body12covered with the protective layer50acquired above are disposed, a portion of the insulating film22at the vicinity of the location at which the first exposed portion34aand the second exposed portion34bof the coil conductor16are disposed, a portion of the insulating film that covers the metal magnetic-body particles, and the protective layer50are removed, and the metal magnetic-body particles are melted. Note that the method of removing the protective layer50can be, in addition to the laser irradiation method, for example, a blasting method or a grinding method.

(G) Formation of External Electrodes

Next, the first external electrode40ais formed on the first end surface12eof the body12, and the second external electrode40bis formed on the second end surface12f.

First, the body12is subjected to electrolytic barrel plating to plate the body12with Cu, as a result of which the underlying electrode layers are formed. Next, the Ni plating layers are formed by plating the surface of each underlying electrode layer with Ni and the Sn plating layers are further formed by plating with Sn, as a result of which the external electrodes40are formed. Therefore, the first exposed portion34aof the coil conductor16is electrically connected to the first external electrode40a, and the second exposed portion34bof the coil conductor16is electrically connected to the second external electrode40b. Note that the underlying electrode layers formed by the plating with Cu may be formed by electroless plating.

The coil component10is manufactured as described above.

Note that the first molded body72and the collective base74may be manufactured by using granulation powder instead of the first magnetic-body sheet70aand the second magnetic-body sheet70b.

In this case, first, the first die is prepared and the coil conductors16are disposed on the first die.

Next, the granulation powder is disposed on the coil conductors16and is press-molded in the direction of the winding axis O, as a result of which the first molded body72is formed. Next, the first molded body72is separated from the second die, is turned upside down, and is disposed on the first die60. Then, the granulation powder is disposed on the first molded body72and is press-molded in the direction of the winding axis O, as a result of which the collective base (the second molded body)74can be fabricated.

The granulation powder for constituting the magnetic-body section14can be acquired by mixing first metal magnetic powder and second metal magnetic powder with thermosetting epoxy resin at a predetermined proportion and kneading the mixture.

When the coil component110is to be manufactured, the coil conductor116that is formed by winding in the form of an edgewise coil the conductive belt body118that is formed from the substantially rectangular wire120covered with the insulating film122is prepared.

The conductive belt body118includes the substantially linear rectangular wire120that is substantially rectangular in cross section, and the insulating film122that covers the surface of the substantially rectangular wire120. In order to acquire the conductive belt body118, first, the entire surface of the substantially rectangular wire120is substantially uniformly coated with the insulating film122. Next, only the plate surfaces118aof the conductive belt body118are further coated with the insulating film122to acquire the conductive belt body118as that shown inFIG.15. Note that only both the plate surfaces118aand the plate surfaces118bmay be further coated with the insulating film122. Therefore, as shown inFIG.16, the conductive belt body118is acquired. The substantially rectangular wire120may be coated with the insulating film122by, for example, dipping.

According to the method of manufacturing the coil component according to the embodiment, by using the coil conductor16, the insulating film22that is disposed on the side of the first principal surface16aof the coil conductor16facing the first principal surface12aof the body12is thick. Therefore, impact resistance is increased, as a result of which it is possible to provide a coil component that makes it possible to suppress occurrence of short-circuit defects that occur when the magnetic-body particles that constitute the magnetic-body section14pierce through the insulating film22.

Note that, although the embodiments of the present disclosure are disclosed in the description above in this way, the present disclosure is not limited to such embodiments.

That is, various changes can be made to the embodiments described above in terms of the mechanism, the shape, the material, the quantity, the position, and the configuration, without departing from the scope of the technical idea and the object of the present disclosure, and such changes are included in the present disclosure.