inductor

Abstract

Provided is an inductor that further improves a coupling coefficient of a plurality of coils that are arranged in a stacking direction. An inductor 1 according to the present disclosure comprises: an element body 10 having a first coil C1 that is configured by stacking a plurality of first conductor layers CD1, and a second coil C2 that is configured by stacking a plurality of second conductor layers CD2; first external electrodes 21a, 21b that are disposed on a mounting surface of the element body 10 and are electrically connected to the first coil C1; and second external electrodes 22a, 22b that are disposed on the mounting surface of the element body 10 and are electrically connected to the second coil C2, wherein at least part of the second coil C2 is disposed between the first conductor layers CD1 of the first coil in the stacking direction of the second conductor layers.

Description

Inductor

[0001] This disclosure relates to an inductor.

[0002] Patent Document 1 discloses a coil component in which two electrically isolated coil conductors are housed in a base, with lead conductors extending from both ends of each coil conductor toward the lower surface of the base, and four external electrodes for surface mounting provided on the lower surface of the base (see Embodiment 2 of Patent Document 1 (particularly Figures 7(a) to (c))).

[0003] Japanese Patent Publication No. 2019-176109

[0004] In the coil component disclosed in Patent Document 1, the two coil conductors are magnetically coupled to each other. However, in a structure where the two coil conductors are simply arranged in a stacking direction, the magnetic coupling between the two coil conductors is insufficient, and there was room for further improvement.

[0005] This disclosure has been made in view of the aforementioned problems. Specifically, the primary purpose of this disclosure is to further improve the coupling coefficient of multiple coils arranged in the stacking direction.

[0006] The inductor of the present disclosure is an inductor comprising: a base body having a first coil formed by stacking a plurality of first conductor layers and a second coil formed by stacking a plurality of second conductor layers; a first external electrode disposed on the mounting surface of the base body and electrically connected to the first coil; and a second external electrode disposed on the mounting surface of the base body and electrically connected to the second coil, wherein at least a portion of the second coil is disposed between the first conductor layers of the first coil in the stacking direction of the second conductor layers.

[0007] The inductor of this disclosure can further improve the coupling coefficient of multiple coils arranged in the stacking direction.

[0008] Figure 1 is a schematic perspective view showing an example of the inductor of the present disclosure. Figure 2 is a schematic perspective view showing an example of the internal structure of the inductor of the present disclosure. Figure 3A is a plan view of one layer structure (layer G1) as the internal structure of the inductor of the present disclosure. Figure 3B is a plan view of one layer structure (layer G2) as the internal structure of the inductor of the present disclosure. Figure 3C is a plan view of one layer structure (layer G3) as the internal structure of the inductor of the present disclosure. Figure 3D is a plan view of one layer structure (layer G4) as the internal structure of the inductor of the present disclosure. Figure 3E is a plan view of one layer structure (layer G5) as the internal structure of the inductor of the present disclosure. Figure 3F is a plan view of one layer structure (layer G6) as the internal structure of the inductor of the present disclosure. Figure 3G is a plan view of one layer structure (layer G7) as the internal structure of the inductor of the present disclosure. Figure 3H is a plan view of one layer structure (layer G8) as the internal structure of the inductor of the present disclosure. Figure 3I is a plan view of one layer structure (layer G9) as the internal structure of the inductor of the present disclosure. Figure 3J is a plan view of one layer structure (layer G10) as the internal structure of the inductor of the present disclosure. Figure 3K is a plan view of one layer structure (layer G11) as the internal structure of the inductor of the present disclosure. Figure 3L is a plan view of one layer structure (layer G12) as the internal structure of the inductor of the present disclosure. Figure 3M is a plan view of one layer structure (layer G13) as the internal structure of the inductor of the present disclosure. Figure 3N is a plan view of one layer structure (layer G14) as the internal structure of the inductor of the present disclosure. Figure 3O is a plan view of one layer structure (layer G15) as the internal structure of the inductor of the present disclosure. Figure 3P is a plan view of one layer structure (layer G16) as the internal structure of the inductor of the present disclosure. Figure 3Q is a plan view of one layer structure (layer G17) as the internal structure of the inductor of the present disclosure. Figure 4 is a schematic exploded perspective view showing an example of the first coil of the present disclosure. Figure 5 is a schematic exploded perspective view showing an example of the second coil of the present disclosure.

[0009] The inductors of this disclosure are described below. However, this disclosure is not limited to the configurations described below and may be modified as appropriate without departing from the gist of this disclosure. Furthermore, combinations of several of the preferred configurations described below also constitute this disclosure.

[0010] The inductor of this disclosure is used, for example, in a DC-DC converter. However, the multilayer inductor of this disclosure may also be applicable to applications other than DC-DC converters.

[0011] In this specification, terms describing relationships between elements (e.g., "parallel," "orthogonal," etc.) and terms describing the shape of elements mean not only strictly defined aspects but also substantially equivalent ranges, such as ranges with differences of a few percent. In this specification, the direction in which the magnetic layer and conductive layer constituting the base material are stacked is referred to as the "stacking direction."

[0012] The drawings shown below are schematic representations, and their dimensions, aspect ratios, and scales may differ from those of the actual product.

[0013] <Inductor> Embodiments of the inductor of this disclosure will be described with reference to Figures 1 to 5. Note that the shape and arrangement of the inductor and its components are not limited to the examples shown.

[0014] The inductor shown in Figure 1 comprises a base body 10, a pair of first external electrodes 21a and 21b provided on the bottom surface of the base body 10, and a pair of second external electrodes 22a and 22b. Each component will be described in detail below.

[0015] -Basic Body- The basic body 10 is, for example, a rectangular prism shape or a roughly rectangular prism shape having six faces. The corners and edges of the basic body 10 may be rounded. The corners are the parts where three faces of the basic body 10 intersect, and the edges are the parts where two faces of the basic body 10 intersect.

[0016] Figure 1 shows the length, width, and height directions of the inductor 1 and the base body 10 as the L, W, and T directions, respectively. The length L, width W, and height T are orthogonal to each other. The mounting surface of the inductor 1 is, for example, a surface parallel to the length L and width W (LW surface).

[0017] The base body 10 shown in Figure 1 has a first main surface 11 and a second main surface 12 facing the height direction T, a first end surface 13 and a second end surface 14 facing the length direction L, and a first side surface 15 and a second side surface 16 facing the width direction W. In the example shown in Figure 1, a pair of first external electrodes 21a, 21b and a pair of second external electrodes 22a, 22b are formed on the first main surface 11 of the base body 10, which corresponds to the mounting surface (bottom surface) of the base body 10.

[0018] The base body 10 is constructed by stacking multiple layers G1 to G17 in the stacking direction. Inside the base body 10 are magnetic material layers ML1 to ML3, a first coil C1 having multiple first conductor layers CD1 (described later), and a second coil C2 having multiple second conductor layers CD2. The second coil C2 is positioned between the first conductor layers CD1 of the first coil C1 in the stacking direction. The boundaries between each layer of the stacked structure of the base body 10 may disappear. Also, layers G1 to G17 may be constructed by stacking multiple identical patterns. Before describing the details of layers G1 to G17, the magnetic material layers ML1 to ML3 used in the inductor 1 of this embodiment will be described.

[0019] The magnetic layers ML1 to ML3 may contain metallic magnetic particles composed of magnetic material. The metallic magnetic particles may contain Fe and / or Si. More specifically, they may be Fe particles or Fe alloy particles. Examples of Fe alloys include Fe-Si alloys, Fe-Si-Cr alloys, Fe-Si-Al alloys, Fe-Si-B-P-Cu-C alloys, Fe-Si-B-Nb-Cu alloys, etc. The metallic magnetic particles may also contain impurities such as Cr, Mn, Cu, Ni, P, S, or Co that are not intended during manufacturing.

[0020] The surface of the aforementioned metallic magnetic particles may be covered with an insulating film. Covering the surface of the metallic magnetic particles with an insulating film can increase the insulation between the metallic magnetic particles. Methods for forming the insulating film on the surface of the metallic magnetic particles include the sol-gel method and the mechanochemical method. The materials constituting the insulating film may be oxides of P, Si, etc., zinc phosphate, or manganese phosphate. The insulating film may also be an oxide film formed by the oxidation of the surface of the metallic magnetic particles. The thickness of the insulating film is preferably 1 nm to 50 nm, more preferably 1 nm to 30 nm, and even more preferably 1 nm to 20 nm. For example, a cross-section obtained by polishing an inductor sample can be photographed with a scanning electron microscope (SEM), and the thickness of the insulating film covering the surface of the metallic magnetic particles can be measured from the obtained SEM image.

[0021] The average particle size of the metallic magnetic particles in the magnetic layers ML1 to ML3 may be selectively used depending on the characteristics, and may include small particles with a relatively small average particle size, large particles with a relatively large average particle size, and medium particles with an average particle size between the small and large particles.

[0022] In this specification, "small metallic magnetic particles" refers to metallic magnetic particles with an average particle size of 1 μm or more and less than 3 μm, "medium metallic magnetic particles" refers to metallic magnetic particles with an average particle size of 3 μm or more and less than 7 μm, and "large metallic magnetic particles" refers to metallic magnetic particles with an average particle size of 7 μm or more.

[0023] The average particle size of the metallic magnetic particles in the magnetic material layer can be measured using the procedure described below. A sample of the inductor is cut to obtain a sample cross-section. Specifically, the sample cross-section is obtained by cutting the sample perpendicular to the mounting surface of the material using a virtual line extending in the width direction of the material through the coil winding axis when viewed from the top surface of the material, and a virtual diagonal line connecting two corners on the top surface through the coil winding axis. For the obtained cross-section, multiple regions (e.g., 5 locations) along the width direction of the material between multiple conductor layers (e.g., 130 μm × 100 μm) and multiple regions (e.g., 5 locations) between the conductor layer and the lead conductor described later (e.g., 130 μm × 100 μm) are photographed with an SEM, and the obtained SEM images are analyzed using image analysis software (e.g., image analysis software WinROOF2021 (manufactured by Mitani Corporation)) to determine the equivalent circle diameter of the metallic magnetic particles. The average value of the obtained equivalent circle diameters is taken as the average particle size of the metallic magnetic particles.

[0024] Here, regarding the insulating properties, when small metallic magnetic particles are used in the magnetic layer, the insulating properties of the magnetic layer are higher than when large metallic magnetic particles are used. This is because, assuming that the thickness of the insulating film covering small metallic magnetic particles is the same as the thickness of the insulating film covering large metallic magnetic particles, when comparing the ratio of insulating film per unit area when small particles are used with the ratio of insulating film per unit area when large particles are used, the ratio of insulating film per unit area is higher when small particles are used.

[0025] On the other hand, regarding magnetic properties (permeability), when small metallic magnetic particles are used in the magnetic layer, the magnetic properties are lower than when large metallic magnetic particles are used. This is because the proportion of magnetic material (e.g., Fe and / or Si) per unit area is higher when large particles are used than when small particles are used.

[0026] Considering the above insulating and magnetic properties, the inductor 1 base body 10 of this embodiment may comprise magnetic layers ML1 to ML3, including a first magnetic layer ML1 containing small metallic magnetic particles, a second magnetic layer ML2 containing medium metallic magnetic particles, and a third magnetic layer ML3 containing large metallic magnetic particles. Furthermore, the inductor base body of this embodiment may optionally include non-magnetic layers. The layers G1 to G17 constituting the base body 10 shown in Figures 3A to 3Q will be described in detail below.

[0027] - Layer G1 (see Figure 3A) Layer G1 is formed using a third magnetic material layer ML3 containing large metallic magnetic particles. Layer G1 may constitute the second main surface 12 of the base body 10. As a result, the permeability of the inductor 1 can be improved because the third magnetic material layer ML3 contains large metallic magnetic particles.

[0028] Layer G2 (see Figure 3B) Layer G2 has a first magnetic layer ML1 and a third magnetic layer ML3.

[0029] The first magnetic layer ML1 of layer G2 is provided to provide insulation in the stacking direction from the first conductor layer CD1 of layer G3, which will be described later. For this reason, a highly insulating magnetic layer is used for the first magnetic layer ML1 of layer G2. In other words, the first magnetic layer ML1 containing small metallic magnetic particles is used. Therefore, the first magnetic layer ML1 of layer G2 corresponds to the outermost insulating layer, which is provided outside the first coil C1 in the stacking direction.

[0030] The first magnetic layer ML1 of layer G2 may be provided along the winding of the first conductive layer CD1 of layer G3 in a plan view. That is, it may be wound along three sides of the outer edge of the element 10. The corner positions (bends) of the first magnetic layer ML1 may be notched.

[0031] In a plan view, the planar area of ​​the first magnetic layer ML1 of layer G2 may be larger than the planar area of ​​the first conductor layer CD1 of layer G3 in order to provide insulation from the first conductor layer CD1 of layer G3. Furthermore, in a plan view, the first magnetic layer ML1 of layer G2 may overlap with the first conductor layer CD1 of layer G3. This allows the first magnetic layer ML1 of layer G2 to cover the first conductor layer CD1 of layer G3, thereby preventing unintended short circuits.

[0032] The third magnetic layer ML3 of layer G2 is arranged around the first magnetic layer ML1 in a plan view. In other words, the third magnetic layer ML3 of layer G2 may be arranged both outside and inside the first magnetic layer ML1 in a plan view. By arranging the third magnetic layer ML3, which contains large metallic magnetic particles, at the location where magnetic flux is generated by the first and second coils, the permeability of the inductor can be improved.

[0033] Layer G3 (see Figure 3C) Layer G3 has a first conductive layer CD1 and a third magnetic layer ML3.

[0034] The first conductor layer CD1 of layer G3 is wound from a position overlapping with the first lead conductor DM1a of layer G4 (described later) in a plan view to a position overlapping with the first connecting conductor CM1 of layer G4. In other words, it may be wound along three sides of the outer edge of the element 10.

[0035] Here, in the first conductor layer CD1 of layer G3, avoidance sections AP may be provided at the corner positions (bends) corresponding to the first external electrode 21b and the corner positions corresponding to the second external electrode 22a in a plan view. The avoidance sections AP may be configured by cutting out the corner positions in the first conductor layer CD1. By providing avoidance sections AP in the first conductor layer CD1 in this way, for example, as will be explained in layer G4 and later, lead conductors or connecting conductors can be placed in the cut-out space. Therefore, by utilizing the cut-out space, the coil diameter can be made as large as possible in a plan view.

[0036] The third magnetic layer ML3 of layer G3 is arranged around the first conductor layer CD1 (i.e., inside and outside the first conductor layer CD1). Furthermore, since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0037] ・Layer G4 (see FIG. 3D) Layer G4 includes a first magnetic layer ML1, a second magnetic layer ML2, a third magnetic layer ML3, a first connection conductor CM1, and a first lead-out conductor DM1a.

[0038] The first magnetic layer ML1 of layer G4 is provided to achieve insulation in the lamination direction with respect to the first conductor layer CD1 of layer G3 and the first conductor layer CD1 of layer G5 described later. Therefore, a magnetic layer with high insulation is used as the first magnetic layer ML1 of layer G4. That is, the first magnetic layer ML1 containing small-sized metal magnetic particles is used. Therefore, the first magnetic layer ML1 of layer G4 corresponds to an interlayer insulating layer between adjacent first conductor layers CD1 in the lamination direction.

[0039] The first magnetic layer ML1 of layer G4 may be wound along four sides of the outer edge of the element body 10 in a plan view. Here, the notches at the corner positions of the first magnetic layer ML1 of layer G4 may be provided corresponding to the notch positions of the first conductor layer CD1 of layer G3 and the notch positions of the first conductor layer CD1 of layer G5 described later. That is, there may be three notches at the corner positions of the first magnetic layer ML1 of layer G4. By adopting such a notch configuration, insulation between the first conductor layer CD1 of layer G3 and the first conductor layer CD1 of layer G5 can be achieved.

[0040] The plane area of the first magnetic layer ML1 of layer G4 in a plan view may be larger than the plane area of the first conductor layer CD1 of layer G3 and the plane area of the first conductor layer CD1 of layer G5, so as to insulate between the first conductor layer CD1 of layer G3 and the first conductor layer CD1 of layer G5. In addition, in a plan view, the first magnetic layer ML1 of layer G4 may overlap the first conductor layer CD1 of layer G3 and the first conductor layer CD1 of layer G5. Such a first magnetic layer ML1 can appropriately function as an interlayer insulating layer between adjacent first conductor layers CD1 in the lamination direction.

[0041] The second magnetic layer ML2 of layer G4 is provided between the first lead conductor DM1a and the first magnetic layer ML1, and is provided at a corner position corresponding to the first external electrode 21a in a plan view. From the viewpoint of improving the magnetic permeability of the inductor while maintaining insulation with the lead conductor, the second magnetic layer ML2 containing medium-sized metal magnetic particles is used at this position. That is, according to the second magnetic layer ML2 of layer G4, both improvement in insulation with the lead conductor and improvement in magnetic permeability of the inductor can be achieved.

[0042] The third magnetic layer ML3 of layer G4 is arranged around the first magnetic layer ML1 (that is, inside and outside the first magnetic layer ML1). Since the third magnetic layer ML3 contains large-sized metal magnetic particles, the magnetic permeability of the inductor 1 can be improved.

[0043] The first connection conductor CM1 of layer G4 is a member for electrically connecting the end of the first conductor layer CD1 of layer G3 and the end of the first conductor layer CD1 of layer G5. The first connection conductor CM1 may use the same metal as that of the first conductor layer CD1. Note that a metal different from that of the first conductor layer CD1 may be used as the metal of the first connection conductor CM1 of layer G4.

[0044] The first connection conductor CM1 of layer G4 may be provided at a position where the end of the first conductor layer CD1 of layer G3 overlaps the end of the first conductor layer CD1 of layer G5 in a plan view. Therefore, the above-mentioned first magnetic layer ML1 may be arranged around the first connection conductor CM1. According to the first connection conductor CM1 of layer G4, the first conductor layer CD1 of layer G3 constituting the first coil C1 and the first conductor layer CD1 of layer G5 can be appropriately electrically connected.

[0045] The first lead conductor DM1a of layer G4 is provided at a position where the end of the first conductor layer CD1 of layer G3 overlaps the first lead conductor DM1a of layer G5 in a plan view. The first lead conductor DM1a of layer G4 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Accordingly, when a voltage is applied to the first external electrodes 21a and 21b, a current flows through the first conductor layer CD1 constituting the first coil C1, and magnetic flux can be generated in the first coil C1.

[0046] Layer G5 (see Figure 3E) Layer G5 has a first conductor layer CD1, a second magnetic material layer ML2, a third magnetic material layer ML3, and a first leaded conductor DM1a.

[0047] The first conductor layer CD1 of layer G5 is wound from a position where it overlaps with the first connecting conductor CM1 of layer G4 in a plan view to a position where it overlaps with the first connecting conductor CM1 of layer G6. In other words, it may be wound along three sides of the outer edge of the element 10.

[0048] In the first conductor layer CD1 of layer G5, a bypass section AP may be provided at the corner position (bend) corresponding to the first lead conductor DM1a in a plan view. By providing the bypass section AP in the first conductor layer CD1 in this way, the first lead conductor DM1a can be placed in the cut-out space. Therefore, by utilizing the cut-out space, the coil diameter can be made as large as possible in a plan view.

[0049] The second magnetic layer ML2 of layer G5 is provided between the first conductor layer CD1 and the first lead conductor DM1a, and is located at a corner position corresponding to the first external electrode 21a in a plan view. At this position, a second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductor. In other words, the second magnetic layer ML2 of layer G5 makes it possible to achieve both improved insulation from the lead conductor and improved permeability of the inductor.

[0050] The third magnetic layer ML3 of layer G5 is arranged around the first conductor layer CD1 (i.e., inside and outside the first conductor layer CD1). Since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0051] The first lead conductor DM1a of layer G5 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G4 and the first lead conductor DM1a of layer G6. The first lead conductor DM1a of layer G5 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0052] Layer G6 (see Figure 3F) Layer G6 comprises a first magnetic layer ML1, a third magnetic layer ML3, a first connecting conductor CM1, and a first leading conductor DM1a.

[0053] The first magnetic layer ML1 of layer G6 is provided to provide insulation in the stacking direction from the first conductor layer CD1 of layer G5 and the second conductor layer CD2 of layer G7, which will be described later. For this reason, a highly insulating magnetic layer is used for the first magnetic layer ML1 of layer G6. In other words, the first magnetic layer ML1 containing small metallic magnetic particles is used. Therefore, the first magnetic layer ML1 of layer G6 corresponds to an inter-coil insulating layer that insulates the first conductor layer CD1 and the second conductor layer CD2 in the stacking direction.

[0054] The third magnetic layer ML3 of layer G6 is positioned in a location corresponding to the inner side of the first conductor layer CD1 (or the second conductor layer CD2). Furthermore, since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0055] The first connecting conductor CM1 of layer G6 is a member for electrically connecting the end of the first conductor layer CD1 of layer G3 to the end of the first conductor layer CD1 of layer G13, which will be described later. Therefore, the first connecting conductor CM1 of layer G6 makes it possible to electrically connect the first conductor layer CD1 located above the second coil C2 in the stacking direction to the first conductor layer CD1 located below the second coil C2.

[0056] The first lead conductor DM1a of layer G6 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G5 and the first lead conductor DM1a of layer G7. The first lead conductor DM1a of layer G6 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0057] Layer G7 (see Figure 3G) Layer G7 includes a second conductor layer CD2, a second magnetic material layer ML2, a third magnetic material layer ML3, a first connecting conductor CM1, and a first leading conductor DM1a.

[0058] The second conductor layer CD2 of layer G7 is wound from a position overlapping with the second lead conductor DM2a of layer G8 (described later) in a plan view to a position overlapping with the second connecting conductor CM2 of layer G8. In other words, it may be wound along three sides of the outer edge of the element 10.

[0059] In the second conductor layer CD2 of layer G7, a relief section AP may be provided at the corner position (bend) corresponding to the first external electrode 21a in a plan view. By providing the relief section AP in the second conductor layer CD2 in this way, the first lead conductor DM1a can be placed in the cut-out space. Therefore, by utilizing the cut-out space, the coil diameter can be made as large as possible in a plan view.

[0060] The second magnetic layer ML2 of layer G7 is provided between the second conductor layer CD2 and the first lead conductor DM1a, and between the second conductor layer CD2 and the first connecting conductor CM1, and is located at corner positions corresponding to the first external electrodes 21a and 21b in a plan view. At these positions, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductor. In other words, the second magnetic layer ML2 of layer G7 makes it possible to achieve both improved insulation from the lead conductor and improved permeability of the inductor.

[0061] The third magnetic layer ML3 of layer G7 is arranged around the second conductor layer CD2 (i.e., inside and outside the second conductor layer CD2). Furthermore, since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0062] The first connecting conductor CM1 of layer G7 is a component for electrically connecting the first connecting conductor CM1 of layer G6 and the first connecting conductor CM1 of layer G8. Therefore, the first connecting conductor CM1 of layer G7 makes it possible to electrically connect the first conductor layer CD1 (layer G5) located above the second coil C2 in the stacking direction with the first conductor layer CD1 (layer G13) located below the second coil C2.

[0063] The first lead conductor DM1a of layer G7 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G6 and the first lead conductor DM1a of layer G8. The first lead conductor DM1a of layer G7 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0064] Layer G8 (see Figure 3H) Layer G8 includes a first magnetic layer ML1, a second magnetic layer ML2, a third magnetic layer ML3, a first connecting conductor CM1, a second connecting conductor CM2, a first leading conductor DM1a, and a second leading conductor DM2a.

[0065] The first magnetic layer ML1 of layer G8 is provided to provide insulation in the stacking direction from the second conductor layer CD2 of layer G7 and the second conductor layer CD2 of layer G9, which will be described later. For this reason, a highly insulating magnetic layer is used for the first magnetic layer ML1 of layer G8. In other words, the first magnetic layer ML1 containing small metallic magnetic particles is used. Therefore, the first magnetic layer ML1 of layer G8 corresponds to an interlayer insulating layer between the second conductor layers CD2 in the stacking direction.

[0066] The first magnetic layer ML1 of layer G8 may be wound along the four sides of the outer edge of the element 10 in a plan view. Here, the notches at the corner positions of the first magnetic layer ML1 of layer G8 may be provided corresponding to the notch positions of the second conductor layer CD2 of layer G7 and the notch positions of the second conductor layer CD2 of layer G9, which will be described later. In other words, there may be three notches at the corner positions of the first magnetic layer ML1 of layer G8. By using this notch configuration, appropriate insulation is achieved between the second conductor layer CD2 of layer G7 and the second conductor layer CD2 of layer G9.

[0067] In a plan view, the planar area of ​​the first magnetic layer ML1 of layer G8 may be larger than the planar area of ​​the second conductor layer CD2 of layer G7 and the second conductor layer CD2 of layer G9, in order to insulate it from the second conductor layer CD2 of layer G7 and the second conductor layer CD2 of layer G9. Furthermore, in a plan view, the first magnetic layer ML1 of layer G8 may overlap with the second conductor layer CD2 of layer G7 and the second conductor layer CD2 of layer G9. Such a first magnetic layer ML1 can appropriately function as an interlayer insulating layer between the second conductor layers CD2 in the stacking direction.

[0068] The second magnetic layer ML2 of layer G8 is provided between the first lead conductor DM1a and the first magnetic layer ML1, between the second lead conductor DM2a and the first magnetic layer ML1, and between the first connecting conductor CM1 and the first magnetic layer ML1, and is provided at corner positions corresponding to the first external electrodes 21a, 21b and the second external electrode 22a in a plan view. At these positions, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductor or connecting conductor. In other words, the second magnetic layer ML2 of layer G8 makes it possible to achieve both improved insulation from the lead conductor or connecting conductor and improved permeability of the inductor.

[0069] The third magnetic layer ML3 of layer G8 is arranged around the first magnetic layer ML1 (i.e., inside and outside the first magnetic layer ML1). Furthermore, since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0070] The first connecting conductor CM1 of layer G8 is a component for electrically connecting the first connecting conductor CM1 of layer G7 and the first connecting conductor CM1 of layer G9. Therefore, the first connecting conductor CM1 of layer G8 makes it possible to electrically connect the first conductor layer CD1 (layer G5) located above the second coil C2 in the stacking direction with the first conductor layer CD1 (layer G13) located below the second coil C2.

[0071] The second connecting conductor CM2 of layer G8 is a component for electrically connecting the end of the second conductor layer CD2 of layer G7 to the end of the second conductor layer CD2 of layer G9. The second connecting conductor CM2 may be made of the same metal as the second conductor layer CD2. However, the second connecting conductor CM2 of layer G8 may be made of a different metal than that used for the second conductor layer CD2.

[0072] The second connecting conductor CM2 of layer G8 may be provided in a position where, in a plan view, the end of the second conductor layer CD2 of layer G7 and the end of the second conductor layer CD2 of layer G9 overlap. Therefore, the first magnetic material layer ML1 described above may be arranged around the second connecting conductor CM2. The second connecting conductor CM2 of layer G8 allows for the appropriate electrical connection between the second conductor layer CD2 of layer G7, which constitutes the second coil C2, and the second conductor layer CD2 of layer G9.

[0073] The first lead conductor DM1a of layer G8 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G7 and the first lead conductor DM1a of layer G9. The first lead conductor DM1a of layer G8 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrode 21a, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0074] The second lead conductor DM2a of layer G8 is positioned in a plan view where the end of the second conductor layer CD2 of layer G7 and the second lead conductor DM2a of layer G9 overlap. The second lead conductor DM2a of layer G8 electrically connects the second conductor layer CD2 of layer G7 and the second external electrode 22a. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 that constitutes the second coil C2, and a magnetic flux can be generated in the second coil C2.

[0075] Layer G9 (see Figure 3I) Layer G9 includes a second conductor layer CD2, a second magnetic material layer ML2, a third magnetic material layer ML3, a first connecting conductor CM1, a first leading conductor DM1a, and a second leading conductor DM2a.

[0076] The second conductor layer CD2 of layer G9 is wound from a position where it overlaps with the second connecting conductor CM2 of layer G8 in a plan view to a position where it overlaps with the second connecting conductor CM2 of layer G10. In other words, it may be wound along the four sides of the outer edge of the element 10.

[0077] In the second conductor layer CD2 of layer G9, avoidance sections AP may be provided at the corner positions (bends) corresponding to the first external electrodes 21a and 21b and the corner position corresponding to the second external electrode 22a in a plan view. By providing avoidance sections AP in the second conductor layer CD2 in this way, the first lead conductor DM1a, the second lead conductor DM2a, and the first connecting conductor CM1 can be arranged in the cut-out space. Therefore, by utilizing the cut-out space, the coil diameter can be made as large as possible in a plan view.

[0078] The second magnetic layer ML2 of layer G9 is provided between the first lead conductor DM1a and the second conductor layer CD2, between the second lead conductor DM2a and the second conductor layer CD2, and between the first connecting conductor CM1 and the first conductor layer CD1, and is provided at corner positions corresponding to the first external electrodes 21a, 21b and the second external electrode 22a in a plan view. At these positions, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductor or connecting conductor. In other words, the second magnetic layer ML2 of layer G9 makes it possible to achieve both improved insulation from the lead conductor or connecting conductor and improved permeability of the inductor.

[0079] The third magnetic layer ML3 of layer G9 is arranged around the second conductor layer CD2 (i.e., inside and outside the second conductor layer CD2). Since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0080] The first connecting conductor CM1 of layer G9 is a component for electrically connecting the first connecting conductor CM1 of layer G8 and the first connecting conductor CM1 of layer G10. Therefore, the first connecting conductor CM1 of layer G9 allows for the electrical connection of the first conductor layer CD1 located above the second coil C2 in the stacking direction with the first conductor layer CD1 located below the second coil C2.

[0081] The first lead conductor DM1a of layer G9 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G8 and the first lead conductor DM1a of layer G10. The first lead conductor DM1a of layer G9 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0082] The second lead conductor DM2a of layer G9 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G8 and the second lead conductor DM2a of layer G10. The second lead conductor DM2a of layer G8 electrically connects the second conductor layer CD2 of layer G7 to the second external electrode 22a. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 that constitutes the second coil C2, generating a magnetic flux in the second coil C2.

[0083] Layer G10 (see Figure 3J) Layer G10 includes a first magnetic layer ML1, a second magnetic layer ML2, a third magnetic layer ML3, a first connecting conductor CM1, a second connecting conductor CM2, a first leading conductor DM1a, and a second leading conductor DM2a.

[0084] The first magnetic layer ML1 of layer G10 is provided to provide insulation in the stacking direction from the second conductor layer CD2 of layer G9 and the second conductor layer CD2 of layer G11, which will be described later. For this reason, a highly insulating magnetic layer is used for the first magnetic layer ML1 of layer G10. In other words, the first magnetic layer ML1 containing small metallic magnetic particles is used. Therefore, the first magnetic layer ML1 of layer G10 corresponds to an interlayer insulating layer between the second conductor layers CD2 in the stacking direction.

[0085] The first magnetic layer ML1 of layer G10 may be wound along the four sides of the outer edge of the element 10 in a plan view. Here, the notches at the corner positions of the first magnetic layer ML1 of layer G10 may be provided corresponding to the notch positions of the second conductor layer CD2 of layer G9 and the notch positions of the first conductor layer CD1 of layer G11, which will be described later. In other words, there may be three notches at the corner positions of the first magnetic layer ML1 of layer G10. By using this notch configuration, insulation is achieved between the second conductor layer CD2 of layer G9 and the second conductor layer CD2 of layer G11.

[0086] In a plan view, the planar area of ​​the first magnetic layer ML1 of layer G10 may be larger than the planar area of ​​the second conductor layer CD2 of layer G9 and the second conductor layer CD2 of layer G11, in order to insulate it from the second conductor layer CD2 of layer G9 and the second conductor layer CD2 of layer G11. Furthermore, in a plan view, the first magnetic layer ML1 of layer G10 may overlap with the second conductor layer CD2 of layer G9 and the second conductor layer CD2 of layer G11. Such a first magnetic layer ML1 can appropriately function as an interlayer insulating layer between the second conductor layers CD2 in the stacking direction.

[0087] The second magnetic layer ML2 of layer G10 is provided between the first lead conductor DM1a and the first magnetic layer ML1, between the second lead conductor DM2a and the first magnetic layer ML1, and between the first connecting conductor CM1 and the first magnetic layer ML1, and is provided at corner positions corresponding to the first external electrodes 21a, 21b and the second external electrode 22a in a plan view. At these positions, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductor or connecting conductor. In other words, the second magnetic layer ML2 of layer G10 makes it possible to achieve both improved insulation from the lead conductor or connecting conductor and improved permeability of the inductor.

[0088] The third magnetic layer ML3 of layer G10 is arranged around the first magnetic layer ML1 (i.e., inside and outside the first magnetic layer ML1). Since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0089] The first connecting conductor CM1 of layer G10 is a component for electrically connecting the first connecting conductor CM1 of layer G9 and the first connecting conductor CM1 of layer G11. Therefore, the first connecting conductor CM1 of layer G10 makes it possible to electrically connect the first conductor layer CD1 (layer G5) located above the second coil C2 in the stacking direction with the first conductor layer CD1 (layer G13) located below the second coil C2.

[0090] The second connecting conductor CM2 of layer G10 is a component for electrically connecting the end of the second conductor layer CD2 of layer G9 to the end of the second conductor layer CD2 of layer G11. The second connecting conductor CM2 may be made of the same metal as the second conductor layer CD2. However, the second connecting conductor CM2 of layer G10 may be made of a different metal than that used for the second conductor layer CD2.

[0091] The second connecting conductor CM2 of layer G10 may be provided in a position where, in a plan view, the end of the second conductor layer CD2 of layer G9 and the end of the second conductor layer CD2 of layer G11 overlap. Therefore, the first magnetic material layer ML1 described above may be arranged around the second connecting conductor CM2. The second connecting conductor CM2 of layer G10 allows for the electrical connection between the second conductor layer CD2 of layer G9, which constitutes the second coil C2, and the second conductor layer CD2 of layer G11.

[0092] The first lead conductor DM1a of layer G10 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G9 and the first lead conductor DM1a of layer G11. The first lead conductor DM1a of layer G10 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0093] The second lead conductor DM2a of layer G10 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G9 and the second lead conductor DM2a of layer G11. The second lead conductor DM2a of layer G10 electrically connects the second conductor layer CD2 of layer G7 and the second external electrode 22a. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 that constitutes the second coil C2, and a magnetic flux can be generated in the second coil C2.

[0094] Layer G11 (see Figure 3K) Layer G11 includes a second conductor layer CD2, a second magnetic material layer ML2, a third magnetic material layer ML3, a first connecting conductor CM1, a first leading conductor DM1a, and a second leading conductor DM2a.

[0095] The second conductor layer CD2 of layer G11 is wound from a position where it overlaps with the second connecting conductor CM2 of layer G10 in a plan view to a position where it overlaps with the second lead conductor DM2b of layer G12. In other words, it may be wound along three sides of the outer edge of the element 10.

[0096] In the second conductor layer CD2 of layer G11, avoidance sections AP may be provided at the corner positions (bends) corresponding to the first external electrode 21b and the corner positions corresponding to the second external electrode 22a in a plan view. By providing avoidance sections AP in the second conductor layer CD2 in this way, the first connecting conductor CM1 and the second leading conductor DM2a can be arranged in the cut-out space. Therefore, by utilizing the cut-out space, the coil diameter can be made as large as possible in a plan view.

[0097] The second magnetic layer ML2 of layer G11 is provided between the first lead conductor DM1a and the second conductor layer CD2, between the second lead conductor DM2a and the second conductor layer CD2, and between the first connecting conductor CM1 and the first conductor layer CD1, and is provided at corner positions corresponding to the first external electrodes 21a, 21b and the second external electrode 22a in a plan view. From the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductor or connecting conductor, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used at these positions. In other words, the second magnetic layer ML2 of layer G11 makes it possible to achieve both improved insulation from the lead conductor or connecting conductor and improved permeability of the inductor.

[0098] The third magnetic layer ML3 of layer G11 is arranged around the second conductor layer CD2 (i.e., inside and outside the second conductor layer CD2). Since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0099] The first connecting conductor CM1 of layer G11 is a member for electrically connecting the first connecting conductor CM1 of layer G10 and the first connecting conductor CM1 of layer G12. Therefore, the first connecting conductor CM1 of layer G11 makes it possible to electrically connect the first conductor layer CD1 (layer G5) located above the second coil C2 in the stacking direction and the first conductor layer CD1 (layer G13) located below the second coil C2.

[0100] The first lead conductor DM1a of layer G11 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G10 and the first lead conductor DM1a of layer G12. The first lead conductor DM1a of layer G11 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0101] The second lead conductor DM2a of layer G11 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G10 and the second lead conductor DM2a of layer G12. The second lead conductor DM2a of layer G10 electrically connects the second conductor layer CD2 of layer G7 to the second external electrode 22a. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 that constitutes the second coil C2, generating a magnetic flux in the second coil C2.

[0102] Layer G12 (see Figure 3L) Layer G12 includes a first magnetic layer ML1, a third magnetic layer ML3, a first connecting conductor CM1, a first leading conductor DM1a, and second leading conductors DM2a and DM2b.

[0103] The first magnetic layer ML1 of layer G12 is provided to provide insulation in the stacking direction from the second conductor layer CD2 of layer G11 and the first conductor layer CD1 of layer G13, which will be described later. For this reason, a highly insulating magnetic layer is used for the first magnetic layer ML1 of layer G11. In other words, the first magnetic layer ML1 containing small metallic magnetic particles is used. Therefore, the first magnetic layer ML1 of layer G12 corresponds to an inter-coil insulating layer that insulates the first conductor layer CD1 and the second conductor layer CD2 in the stacking direction.

[0104] The third magnetic layer ML3 of layer G12 is positioned in a location corresponding to the inner side of the first conductor layer CD1 (or the second conductor layer CD2). Furthermore, since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0105] The first connecting conductor CM1 of layer G12 is a member for electrically connecting the first connecting conductor CM1 of layer G11 and the end of the first conductor layer CD1 of layer G13. Therefore, the first connecting conductor CM1 of layer G12 makes it possible to electrically connect the first conductor layer CD1 (layer G5) located above the second coil C2 in the stacking direction with the first conductor layer CD1 (layer G13) located below the second coil C2.

[0106] The first lead conductor DM1a of layer G12 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G11 and the first lead conductor DM1a of layer G13. The first lead conductor DM1a of layer G12 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0107] The second lead conductor DM2a of layer G12 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G11 and the second lead conductor DM2a of layer G13. The second lead conductor DM2a of layer G12 electrically connects the second conductor layer CD2 of layer G7 and the second external electrode 22a. The second lead conductor DM2b of layer G12 is positioned in a plan view where it overlaps with the end of the second conductor layer CD2 of layer G11 and the second lead conductor DM2b of layer G13. The second lead conductor DM2b of layer G12 electrically connects the second conductor layer CD2 of layer G11 and the second external electrode 22b. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 constituting the second coil C2, generating a magnetic flux in the second coil C2.

[0108] Layer G13 (see Figure 3M) Layer G13 includes a first conductor layer CD1, a second magnetic layer ML2, a third magnetic layer ML3, a first lead conductor DM1a, and second lead conductors DM2a and DM2b.

[0109] The first conductor layer CD1 of layer G13 is wound from a position where it overlaps with the first connecting conductor CM1 of layer G12 in a plan view to a position where it overlaps with the first connecting conductor CM1 of layer G14. In other words, it may be wound along the four sides of the outer edge of the element 10.

[0110] In the first conductor layer CD1 of layer G13, avoidance sections AP may be provided at the corner positions corresponding to the first external electrode 21a and the second external electrodes 22a and 22b in a plan view. By providing avoidance sections AP in the first conductor layer CD1 in this way, the first lead conductor DM1a and the second lead conductors DM2a and DM2b can be arranged in the cut-out space. Therefore, by utilizing the cut-out space, the coil diameter can be made as large as possible in a plan view.

[0111] The second magnetic layer ML2 of layer G13 is provided between the first lead conductor DM1a and the first conductor layer CD1, between the second lead conductor DM2a and the first conductor layer CD1, between the second lead conductor DM2b and the first conductor layer CD1, and between the ends of the first conductor layer CD1. At these locations, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining the insulation between the lead conductors or between the first conductor layers CD1 in a plan view. In other words, the second magnetic layer ML2 of layer G13 makes it possible to achieve both improved insulation between the lead conductors or between the first conductor layers CD1 in a plan view and improved permeability of the inductor.

[0112] The third magnetic layer ML3 of layer G13 may be arranged inside and outside the first conductor layer CD1. Furthermore, since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0113] The first lead conductor DM1a of layer G13 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G12 and the first lead conductor DM1a of layer G14. The first lead conductor DM1a of layer G13 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0114] The second lead conductor DM2a of layer G13 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G12 and the second lead conductor DM2a of layer G14. The second lead conductor DM2a of layer G12 electrically connects the second conductor layer CD2 of layer G7 and the second external electrode 22a. The second lead conductor DM2b of layer G13 is positioned in a plan view where it overlaps with the second lead conductor DM2b of layer G12 and the second lead conductor DM2b of layer G14. The second lead conductor DM2b of layer G13 electrically connects the second conductor layer CD2 of layer G11 and the second external electrode 22b. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 constituting the second coil C2, generating a magnetic flux in the second coil C2.

[0115] Layer G14 (see Figure 3N) Layer G14 includes a first magnetic layer ML1, a second magnetic layer ML2, a third magnetic layer ML3, a first connecting conductor CM1, a first leading conductor DM1a, and second leading conductors DM2a and DM2b.

[0116] The first magnetic layer ML1 of layer G14 is provided to provide insulation in the stacking direction from the first conductor layer CD1 of layer G13 and the first conductor layer CD1 of layer G15, which will be described later. For this reason, a highly insulating magnetic layer is used for the first magnetic layer ML1 of layer G14. In other words, the first magnetic layer ML1 containing small metallic magnetic particles is used. Therefore, the first magnetic layer ML1 of layer G14 corresponds to an interlayer insulating layer between the first conductor layers CD1 in the stacking direction.

[0117] The second magnetic layer ML2 of layer G14 is provided between the first lead conductor DM1a and the first conductor layer CD1, between the second lead conductor DM2a and the first conductor layer CD1, and between the second lead conductor DM2b and the first conductor layer CD1. At these locations, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation between the lead conductors or between the first conductor layers CD1 in a plan view. In other words, the second magnetic layer ML2 of layer G14 makes it possible to achieve both improved insulation between the lead conductors or between the first conductor layers CD1 in a plan view and improved permeability of the inductor.

[0118] The third magnetic layer ML3 of layer G14 is arranged around the first magnetic layer ML1 (i.e., inside and outside the first magnetic layer ML1). Since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0119] The first connecting conductor CM1 of layer G14 is a member for electrically connecting the end of the first conductor layer CD1 of layer G13 to the end of the first conductor layer CD1 of layer G15. The first connecting conductor CM1 may be made of the same metal as the first conductor layer CD1. However, the first connecting conductor CM1 of layer G14 may be made of a different metal than that used for the first conductor layer CD1.

[0120] The first connecting conductor CM1 of layer G14 may be provided at a position where, in a plan view, the end of the first conductor layer CD1 of layer G13 and the end of the first conductor layer CD1 of layer G15 overlap. Therefore, the first magnetic material layer ML1 described above may be arranged around the first connecting conductor CM1. The first connecting conductor CM1 of layer G14 allows for the electrical connection of the first conductor layer CD1 of layer G13, which appropriately constitutes the first coil C1, and the first conductor layer CD1 of layer G15.

[0121] The first lead conductor DM1a of layer G14 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G13 and the first lead conductor DM1a of layer G15. The first lead conductor DM1a of layer G14 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0122] The second lead conductor DM2a of layer G14 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G13 and the second lead conductor DM2a of layer G15. The second lead conductor DM2a of layer G14 electrically connects the second conductor layer CD2 of layer G7 and the second external electrode 22a. The second lead conductor DM2b of layer G14 is positioned in a plan view where it overlaps with the second lead conductor DM2b of layer G13 and the second lead conductor DM2b of layer G15. The second lead conductor DM2b of layer G14 electrically connects the second conductor layer CD2 of layer G11 and the second external electrode 22b. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 constituting the second coil C2, generating a magnetic flux in the second coil C2.

[0123] Layer G15 (see Figure 3O) Layer G15 has a first conductor layer CD1, a second magnetic layer ML2, a third magnetic layer ML3, a first lead conductor DM1a, and second lead conductors DM2a and DM2b.

[0124] The first conductor layer CD1 of layer G15 extends from a position where it overlaps with the first connecting conductor CM1 of layer G14 in a plan view to a position where it overlaps with the first leading conductor DM1b of layer G16.

[0125] The second magnetic layer ML2 of layer G15 is provided at positions corresponding to the first lead conductor DM1a and the second lead conductors DM2a and DM2b. At these positions, the second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductors. In other words, the second magnetic layer ML2 of layer G15 makes it possible to achieve both improved insulation from the lead conductors and improved permeability of the inductor.

[0126] The first lead conductor DM1a of layer G15 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G14 and the first lead conductor DM1a of layer G16. The first lead conductor DM1a of layer G15 electrically connects the first conductor layer CD1 of layer G3 and the first external electrode 21a. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 that constitutes the first coil C1, and a magnetic flux can be generated in the first coil C1.

[0127] The second lead conductor DM2a of layer G15 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G14 and the second lead conductor DM2a of layer G16. The second lead conductor DM2a of layer G15 electrically connects the second conductor layer CD2 of layer G7 and the second external electrode 22a. The second lead conductor DM2b of layer G15 is positioned in a plan view where it overlaps with the second lead conductor DM2b of layer G14 and the second lead conductor DM2b of layer G16. The second lead conductor DM2b of layer G15 electrically connects the second conductor layer CD2 of layer G11 and the second external electrode 22b. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 constituting the second coil C2, generating a magnetic flux in the second coil C2.

[0128] Layer G16 (see Figure 3P) Layer G16 has a first magnetic layer ML1, a second magnetic layer ML2, a third magnetic layer ML3, first lead conductors DM1a and DM1b, and second lead conductors DM2a and DM2b.

[0129] The first magnetic layer ML1 of layer G16 may be provided so as to cover the first conductive layer CD1 of layer G15 when viewed from the bottom. Therefore, the first magnetic layer ML1 of layer G16 is insulated from the first conductive layer CD1 of layer G15 in the stacking direction. Accordingly, a highly insulating magnetic layer is used for the first magnetic layer ML1 of layer G16. In other words, the first magnetic layer ML1 containing small metallic magnetic particles is used.

[0130] The second magnetic layer ML2 of layer G16 is provided at a position that contacts the first lead conductors DM1a and DM1b, and the second lead conductors DM2a and DM2b. At this position, a second magnetic layer ML2 containing medium-sized metallic magnetic particles is used from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductors. In other words, the second magnetic layer ML2 of layer G16 makes it possible to achieve both improved insulation from the lead conductors and improved permeability of the inductor.

[0131] The third magnetic layer ML3 of layer G16 is arranged around the first magnetic layer ML1, the second magnetic layer ML2, the first lead conductors DM1a and DM1b, and the second lead conductors DM2a and DM2b. Since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0132] The first lead conductor DM1a of layer G16 is positioned in a plan view where it overlaps with the first lead conductor DM1a of layer G15 and the first lead conductor DM1a of layer G17. The first lead conductor DM1a of layer G16 electrically connects the first conductor layer CD1 of layer G3 and the first external electrodes 21a and 21b. Similarly, the first lead conductor DM1b of layer G16 is positioned in a plan view where it overlaps with the first conductor layer CD1 of layer G15 and the first lead conductor DM1b of layer G17. The first lead conductor DM1b of layer G16 electrically connects the first conductor layer CD1 of layer G15 and the first external electrode 21b. Therefore, when a voltage is applied to the first external electrodes 21a and 21b, current flows through the first conductor layer CD1 constituting the first coil C1, generating a magnetic flux in the first coil C1.

[0133] The second lead conductor DM2a of layer G16 is positioned in a plan view where it overlaps with the second lead conductor DM2a of layer G15 and the second lead conductor DM2a of layer G17. The second lead conductor DM2a of layer G15 electrically connects the second conductor layer CD2 of layer G7 and the second external electrode 22a. The second lead conductor DM2b of layer G16 is positioned in a plan view where it overlaps with the second lead conductor DM2b of layer G15 and the second lead conductor DM2b of layer G17. The second lead conductor DM2b of layer G16 electrically connects the second conductor layer CD2 of layer G11 and the second external electrode 22b. Therefore, when a voltage is applied to the second external electrodes 22a and 22b, current flows through the second conductor layer CD2 constituting the second coil C2, generating a magnetic flux in the second coil C2.

[0134] Layer G17 (see Figure 3Q) Layer G17 has a second magnetic layer ML2, a third magnetic layer ML3, first lead conductors DM1a and DM1b, and second lead conductors DM2a and DM2b.

[0135] The second magnetic layer ML2 of layer G17 is positioned in a plan view to contact the first lead conductor DM1a and the second lead conductors DM2a and DM2b of layer G16. This position utilizes a second magnetic layer ML2 containing medium-sized metallic magnetic particles, from the viewpoint of improving the permeability of the inductor while maintaining insulation from the lead conductors. In other words, the second magnetic layer ML2 of layer G17 allows for both improved insulation from the lead conductors and improved permeability of the inductor.

[0136] The third magnetic layer ML3 of layer G17 is arranged around the second magnetic layer ML2, the first lead conductors DM1a and DM1b, and the second lead conductors DM2a and DM2b. The third magnetic layer ML3 of layer G17 may constitute the first main surface 11 of the element 10. Furthermore, since the third magnetic layer ML3 contains large metallic magnetic particles, the permeability of the inductor 1 is improved.

[0137] In a plan view, the first lead conductors DM1a and DM1b of layer G17 electrically connect the first lead conductors DM1a and DM1b of layer G16 to the first external electrodes 21a and 21b. The second lead conductors DM2a and DM2b of layer G17 electrically connect the second lead conductor DM2 of layer G16 to the second external electrodes 22a and 22b in a plan view.

[0138] As described above, if the base body 10 has a laminated structure comprising layers G1 to G17, the design freedom of the inductor 1 is increased. For example, when manufacturing an inductor 1 having first external electrodes 21a, 21b and second external electrodes 22a, 22b on the bottom surface (first main surface 11) of the base body 10, it becomes easier to pull out the first coil C1 and the second coil C2 to the bottom surface side.

[0139] When manufacturing the above-described laminated structure, magnetic pastes may be prepared as the first magnetic layer ML1 to the third magnetic layer ML3, and conductive pastes as the first conductor layer CD1, the second conductor layer CD2, the first lead conductors DM1a and DM1b, and the second lead conductors DM2a and DM2b.

[0140] Magnetic paste is prepared by kneading metallic magnetic powder, such as Fe-Si alloy or Fe-Si-Cr alloy, of a desired particle size, with a binder such as cellulose or polyvinyl butyral (PVB) and a solvent such as a mixture of terpineol and butyl diglycol acetate (BCA).

[0141] As a conductive paste, for example, a paste containing Ag as a conductive material is prepared.

[0142] After preparing the magnetic paste, conductive paste, and non-magnetic paste described above, the laminated structure comprising the layers G1 to G17 may be formed by stacking them by sequential printing (for example, screen printing) from the second main surface 12 side or the first main surface 11 side of the base body 10. In this case, each of the layers G1 to G17 may be printed repeatedly until the desired thickness is reached. Then, the base body 10 of the inductor 1 of this disclosure is prepared by firing the laminated structure.

[0143] Subsequently, first external electrodes 21a, 21b and second external electrodes 22a, 22b are formed on the mounting surface of the base body 10 by electroplating. The plating material may be Cu plating. Other materials include, but are not limited to, Ni-Sn, Ni-Au, Ni-Cu, and / or Cu-Ni-Au. After the external electrodes are formed, the element can be cut into individual pieces to manufacture the inductor of this disclosure.

[0144] Here, one of the features of the inductor 1 of this disclosure is that the second coil C2 is arranged between the first conductor layers CD1 in the stacking direction. Specifically, the second conductor layers CD2 of layers G7 to G11 that constitute the second coil C2 are arranged between the first conductor layer CD1 of layer G5 and the first conductor layer CD1 of layer G13 in the stacking direction. In other words, unlike the structure of Patent Document 1 in which two coils are simply arranged in the stacking direction, the inductor 1 of this disclosure is magnetically coupled to the first coil C1 on both the upper and lower sides of the second coil C2 in the stacking direction. Therefore, the magnetic coupling can be improved compared to the structure of Patent Document 1. That is, the coupling coefficient of the multiple coils can be further improved.

[0145] One preferred feature of the inductor of this disclosure is that the first conductor layer CD1 and the second conductor layer CD2 may each be provided with avoidance sections AP to avoid the first lead conductors DM1a, DM1b and the second lead conductors DM2a, DM2b. By providing avoidance sections AP in the first conductor layer CD1 and the second conductor layer CD2 in this way, the first lead conductors DM1a, DM1b and the second lead conductors DM2a, DM2b can be arranged in the avoided space. Therefore, the coil diameter can be made as large as possible in plan view while utilizing the space avoided by the avoidance sections AP.

[0146] One preferred feature of the inductor of this disclosure is that, in a plan view, an interconductor insulating layer (a second magnetic layer ML2 consisting of layers G4 to G5, layers G7 to G11, and layers G13 to G17) may be arranged between the first conductor layer CD1 and the first lead conductor DM1a, and / or between the second conductor layer CD2 and the second lead conductor DM2a. Such an interconductor insulating layer can provide electrical insulation between the first conductor layer CD1 and the first lead conductor DM1a, and / or between the second conductor layer CD2 and the second lead conductor DM2a.

[0147] Furthermore, the interconductor insulating layers (the second magnetic material layers ML2 of layers G4 to G5, G7 to G11, and G13 to G17) may be formed of metallic magnetic particles having an average particle size smaller than the average particle size of the metallic magnetic particles constituting the metallic magnetic material (third magnetic material layer ML3) located inside the windings of the first coil C1 or the second coil C2 in the base body 10. Specifically, the average particle size of the metallic magnetic particles contained in the third magnetic material layer ML3 is 7 μm or larger, and the average particle size of the metallic magnetic particles contained in the second magnetic material layer ML2 may be 3 μm or larger and smaller than 7 μm. With this relationship of average particle sizes, appropriate electrical insulation can be achieved between the first conductor layers CD1 and between the second conductor layers CD2. In addition, although the second magnetic material layer ML2 (interconductor insulating layer) of layers G4 to G5, G7 to G11, and G13 to G17 described above uses a magnetic material, the interconductor insulating layer may be a non-magnetic layer as described later.

[0148] The non-magnetic layer may contain, as non-magnetic materials, glass, ceramic materials such as alumina, non-magnetic ferrite materials, and the like. The non-magnetic layer preferably contains a non-magnetic ferrite material as the non-magnetic material. As the non-magnetic ferrite material, Fe is Fe ２ O ３ converted to 40 mol% or more and 49.5 mol% or less based on the entire non-magnetic layer, Cu converted to CuO is 6 mol% or more and 12 mol% or less based on the entire non-magnetic layer, with the balance being ZnO. A non-magnetic ferrite material having the above composition can be used. The non-magnetic material may optionally contain Mn as an additive ３ O ４ , Co ３ O ４ , SnO ２ , Bi ２ O ３ and SiO ２ and the like, and may also contain a trace amount of unavoidable impurities. The non-magnetic layer preferably contains Zn—Cu-based ferrite.

[0149] As one of the preferred features of the inductor of the present disclosure, an inter-coil insulating layer (first magnetic layer ML1 of layer G6 and layer G12) may be provided between the first coil C1 and the second coil C2 in the lamination direction. According to such an inter-coil insulating layer, the first coil C1 and the second coil C2 arranged in the lamination direction can be electrically insulated from each other.

[0150] Furthermore, the inter-coil insulating layer (the first magnetic layer ML1 of layers G6 and G12) may be formed of metallic magnetic particles having an average particle size smaller than the average particle size of the metallic magnetic particles constituting the metallic magnetic material (third magnetic layer ML3) located inside the windings of the first coil C1 or the second coil C2 in the base body 10. Specifically, the average particle size of the metallic magnetic particles contained in the third magnetic layer ML3 is 7 μm or larger, and the average particle size of the metallic magnetic particles contained in the first magnetic layer ML1 may be 1 μm or larger and smaller than 3 μm. With this relationship of average particle sizes, the first coil and the second coil can be magnetically coupled while ensuring insulation between them. Although the first magnetic layer ML1 (inter-coil insulating layer) of layers G6 and G12 described above uses a magnetic material, the inter-conductor insulating layer may be a non-magnetic layer as described above.

[0151] One preferred feature of the inductor of this disclosure is that interlayer insulating layers (first magnetic layers ML1 of layers G4, G8, G10, and G14) may be provided between the first conductor layers CD1 and / or between the second conductor layers CD2, along the windings of the first conductor layers CD1 and / or the windings of the second conductor layers CD2. Such interlayer insulating layers can provide electrical insulation between the first conductor layers CD1, which are the interlayers of the first coil C1, and electrical insulation between the second conductor layers CD2, which are the interlayers of the second coil C2.

[0152] Furthermore, the interlayer insulating layer (the first magnetic layer ML1 of layers G4, G8, G10, and G14) may be formed of metallic magnetic particles having an average particle size smaller than the average particle size of the metallic magnetic particles constituting the metallic magnetic material (third magnetic layer ML3) located inside the windings of the first coil C1 or the second coil C2 in the base body 10. Specifically, the average particle size of the metallic magnetic particles contained in the third magnetic layer ML3 is 7 μm or larger, and the average particle size of the metallic magnetic particles contained in the first magnetic layer ML1 may be 1 μm or larger and smaller than 3 μm. With this relationship of average particle sizes, appropriate electrical insulation can be achieved between the first conductor layers CD1 and between the second conductor layers CD2. Although the above description of the first magnetic layer ML1 (interlayer insulating layer) of layers G4, G8, G10, and G14 describes the use of magnetic materials, the interlayer insulating layer may also be a non-magnetic layer as described above.

[0153] One preferred feature of the inductor of this disclosure is that, in the stacking direction, the outermost insulating layer (the first magnetic layer ML1 of layer G2) may be provided outside the first coil C1. Such an outermost insulating layer prevents the first coil C1 from being exposed from the base body 10 and prevents unintended short circuits to the first coil C1.

[0154] Furthermore, the outermost insulating layer (the first magnetic layer ML1 of layer G2) may be formed of metallic magnetic particles having an average particle size smaller than the average particle size of the metallic magnetic particles constituting the metallic magnetic material (third magnetic layer ML3) located inside the windings of the first coil C1 or the second coil C2 in the base body 10. Specifically, the average particle size of the metallic magnetic particles contained in the third magnetic layer ML3 is 7 μm or larger, and the average particle size of the metallic magnetic particles contained in the first magnetic layer ML1 may be 1 μm or larger and smaller than 3 μm. With this relationship of average particle sizes, unintended short circuits to the first coil C1 can be appropriately prevented. Although the first magnetic layer ML1 (interlayer insulating layer) of layer G2 described above uses a magnetic material, the interlayer insulating layer may be the non-magnetic layer described above.

[0155] One of the preferred features of the inductor of this disclosure is that the average particle size (7 μm or more) of the metal magnetic particles constituting the metal magnetic material (third magnetic material layer ML3) located inside the windings of the first coil C1 or the second coil C2 in the base body 10 is the average particle size (3 μm or more and less than 7 μm) of the metal magnetic particles constituting the interconductor insulating layer (second magnetic material layer ML2 of layers G4 to G5, layers G7 to G11, and layers G13 to G17), and the metal magnetic particles constituting the intercoil insulating layer (first magnetic material layer ML1 of layers G6 and G12) are the average particle size (3 μm or more and less than 7 μm). The average particle size of the particles (1 μm or more and less than 3 μm), or the average particle size of the metallic magnetic particles constituting the interlayer insulating layer (first magnetic layer ML1 of layers G4, G8, G10, and G14) (1 μm or more and less than 3 μm), or the average particle size of the metallic magnetic particles constituting the outermost insulating layer (first magnetic layer ML1 of layer G2) (1 μm or more and less than 3 μm), may be larger than that of the interconductor insulating layer, the intercoil insulating layer, the interlayer insulating layer, and the outermost insulating layer. In this way, the inductor of this disclosure can improve insulation properties and magnetic properties by selectively using at least three types of metallic magnetic particles, such as small particles, medium particles, and large particles, as magnetic layers according to their characteristics.

[0156] One preferred feature of the inductor of this disclosure is that the number of turns of the first conductor layer CD1 (layers G3 and G5) located above the second coil C2 in the stacking direction may be different from the number of turns of the first conductor layer CD1 (layers G13 and G15) located below the second coil C2 in the stacking direction. In this specification, "number of turns" is defined as "number of turns: 1" when the conductor layer has been turned around once. In this embodiment, the number of turns of the first conductor layer CD1 (layers G3 and G5) located above the second coil C2 in the stacking direction is 1.25, and the number of turns of the first conductor layer CD1 (layers G13 and G15) located below the second coil C2 in the stacking direction is 1.

[0157] Here, the inductor of this disclosure has a mounting surface on the lower side in the stacking direction and is drawn out toward the lower side in the stacking direction by the first lead conductors DM1a and DM1b. Therefore, it is preferable that the number of turns of the first coil C1 is greater than the number of turns of the first conductor layer CD1 (layers G3 and G5) on the upper side in the stacking direction (=1.25) than the number of turns of the first conductor layer CD1 (layers G3 and G5) on the lower side in the stacking direction (=1). However, this embodiment is not limited to this one, and the number of turns of the first conductor layer CD1 (layers G3 and G5) on the lower side in the stacking direction may be greater than the number of turns of the first conductor layer CD1 (layers G3 and G5) on the upper side in the stacking direction.

[0158] Furthermore, regarding the number of turns of the inductor in this disclosure, the total number of turns of the first coil C1 and the total number of turns of the second coil C2 may be substantially equal. For example, in the illustrated example, the total number of turns of the first coil C1 is 2.25, and the total number of turns of the second coil C2 (layers G7, G9, and G11) is also 2.25. In this way, when the total number of turns of the first coil C1 and the total number of turns of the second coil C2 are the same, the mismatch in the DC resistance Rdc between the first coil C1 and the second coil C2 can be reduced.

[0159] One of the preferred features of the inductor of this disclosure is that the winding patterns of the first conductor layer CD1 and the second conductor layer CD2 may be configured along the outer circumference of the element 10. In other words, in layers G1 to G17, there are no layers in which the first conductor layer CD1 and the second conductor layer CD2 coexist. Because of this configuration, the winding pattern of the first conductor layer CD1 or the second conductor layer CD2 can be made as large as possible in plan view.

[0160] The embodiments disclosed herein are illustrative in all respects and do not constitute a limiting interpretation. Therefore, the technical scope of this disclosure is not construed solely by the embodiments described above, but is defined based on the claims. Furthermore, the technical scope of this disclosure includes all modifications within the meaning and scope of equivalence to the claims.

[0161] The inductor of this disclosure can be suitably used as an electronic component that further reduces DC resistance while appropriately maintaining the magnetic coupling of multiple coils.

[0162] 1 Inductor 10 Base C1 First coil C2 Second coil CD1 First conductor layer CD2 Second conductor layer ML1 First magnetic layer ML2 Second magnetic layer ML3 Third magnetic layer CM1 First connecting conductor CM2 Second connecting conductor DCM Lead-out connecting conductor DM1a, DM1b First lead-out conductor DM2a, DM2b Second lead-out conductor AP Avoidance section 21a, 21b First external electrode 22a, 22b Second external electrode G1 to G17 Layers

Claims

1. An inductor comprising: a base body having a first coil formed by stacking multiple first conductor layers and a second coil formed by stacking multiple second conductor layers; a first external electrode disposed on the mounting surface of the base body and electrically connected to the first coil; and a second external electrode disposed on the mounting surface of the base body and electrically connected to the second coil, wherein at least a portion of the second coil is disposed between the first conductor layers of the first coil in the stacking direction of the second conductor layers.

2. The inductor according to claim 1, comprising: a first lead conductor electrically connected to the end of the first coil, extending in the stacking direction and leading out to the mounting surface, and electrically connected to the first external electrode; and a second lead conductor electrically connected to the end of the second coil, extending in the stacking direction and leading out to the mounting surface, and electrically connected to the second external electrode, wherein the plurality of first conductor layers and the plurality of second conductor layers are provided with avoidance portions that avoid the first lead conductor and the second lead conductor.

3. The inductor according to claim 1 or 2, comprising: a first lead conductor electrically connected to the end of the first coil, extending in the stacking direction and leading out to the mounting surface, and electrically connected to the first external electrode; and a second lead conductor electrically connected to the end of the second coil, extending in the stacking direction and leading out to the mounting surface, and electrically connected to the second external electrode, wherein in a plan view, an interconductor insulating layer is disposed between the first conductor layer and the first lead conductor, and / or between the second conductor layer and the second lead conductor.

4. The inductor according to claim 3, wherein the interconductor insulating layer is made of a non-magnetic material, or is made of metallic magnetic particles having an average particle size smaller than the average particle size of metallic magnetic particles constituting a metallic magnetic material located inside the windings of the first coil or the second coil in the substrate.

5. The inductor according to any one of claims 1 to 4, wherein an inter-coil insulating layer is provided between the first coil and the second coil in the stacking direction.

6. The inductor according to claim 5, wherein the inter-coil insulating layer is made of a non-magnetic material, or is made of metallic magnetic particles having an average particle size smaller than the average particle size of metallic magnetic particles constituting a metallic magnetic material located inside the windings of the first coil or the second coil in the substrate.

7. The inductor according to any one of claims 1 to 6, wherein an interlayer insulating layer is provided between the first conductor layers and / or between the second conductor layers in the stacking direction, along the winding of the first conductor layer and / or the winding of the second conductor layer.

8. The inductor according to claim 7, wherein the interlayer insulating layer is made of a non-magnetic material, or is made of metallic magnetic particles having an average particle size smaller than the average particle size of metallic magnetic particles constituting a metallic magnetic material located inside the windings of the first coil or the second coil in the substrate.

9. The inductor according to any one of claims 1 to 8, wherein the outermost insulating layer is provided outside the first coil in the stacking direction.

10. The inductor according to claim 9, wherein the insulating outermost layer is made of a non-magnetic material, or is made of metallic magnetic particles having an average particle size smaller than the average particle size of metallic magnetic particles constituting a metallic magnetic material located inside the windings of the first coil or the second coil in the substrate.

11. A first lead conductor is electrically connected to the end of the first coil, extends in the stacking direction and is drawn out to the mounting surface, and is electrically connected to the first external electrode. A second lead conductor is electrically connected to the end of the second coil, extends in the stacking direction and is drawn out to the mounting surface, and is electrically connected to the second external electrode. In a plan view, an interconductor insulating layer is disposed between the first conductor layer and the first lead conductor, and / or between the second conductor layer and the second lead conductor. In the stacking direction, an intercoil insulating layer is provided between the first conductor layers and / or between the second conductor layers, along the winding of the first conductor layer and / or the winding of the second conductor layer. In the stacking direction, an outermost insulating layer is provided outside the first coil. The inductor according to any one of claims 1 to 10, wherein the average particle size of the metallic magnetic particles constituting the metallic magnetic material located inside the winding of the first coil or the second coil in the substrate is greater than the average particle size of the metallic magnetic particles constituting the interconductor insulating layer, the average particle size of the metallic magnetic particles constituting the intercoil insulating layer, or the average particle size of the metallic magnetic particles constituting the interlayer insulating layer or the average particle size of the metallic magnetic particles constituting the outermost insulating layer, and the average particle size of the metallic magnetic particles constituting the interconductor insulating layer is greater than the average particle size of the metallic magnetic particles constituting the intercoil insulating layer, or the average particle size of the metallic magnetic particles constituting the interlayer insulating layer or the average particle size of the metallic magnetic particles constituting the outermost insulating layer.

12. The inductor according to any one of claims 1 to 11, wherein the number of turns of the first conductor layer above the second coil in the stacking direction and the number of turns of the first conductor layer below the second coil in the stacking direction are different from each other.

13. In plan view, the winding pattern of the first conductor layer and the winding pattern of the second conductor layer are each configured along the outer circumference of the main body, the inductor according to any one of claims 1 to 12.

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