Coil component

Abstract

To provide a coil component with which it is possible to reduce losses.SOLUTION: A coil component 1 comprises an element body 2 and a coil 8, with each of a plurality of coil conductors CC having a rectangular shape in a cross section orthogonal to the extending direction of the coil conductors CC and including corners C1, C2, C2, C4. At least some of the plurality of coil conductors CC are arranged facing each other in a first direction D1. The element body 2 is located between mutually adjacent coil conductors CC in the first direction D1 as seen from the extending direction of the coil conductors, and includes a first section A1 covering at least some of the corners C1, C2, C2, C4 of the coil conductors CC and a second section A2 surrounding the coil conductors CC. The average grain diameter of a metal magnetic particle P1 located in the first section A1 is smaller than the average grain diameter of a metal magnetic particle P2 located in the second section A2.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] A known coil component includes an element body formed to contain a plurality of metal magnetic particles of a soft magnetic material, and a coil disposed within the element body and composed of a plurality of coil conductors (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-139981 Summary of the Invention [Problem to be solved by the invention]

[0004] In coil components, it is desirable to reduce the resistance of the coil conductor from the viewpoint of improving the Q value. To reduce the resistance of the coil conductor, a configuration is used in which the cross-sectional shape of the coil conductor is made rectangular and the cross-sectional area of ​​the coil conductor is increased. However, in a configuration in which coil conductors are adjacent to each other, magnetic saturation occurs due to magnetic flux concentration at the corners of the coil conductor, which reduces the DC superposition characteristics and causes losses.

[0005] An object of one aspect of the present invention is to provide a coil component that can reduce loss. [Means for solving the problem]

[0006] (1) A coil component according to one aspect of the present invention comprises a base body formed by stacking a plurality of magnetic layers each containing a plurality of metal magnetic particles of a soft magnetic material, and a coil disposed within the base body and composed of a plurality of coil conductors, each of which has a rectangular shape and corners in a cross section perpendicular to the extension direction of the coil conductor, and at least some of the coil conductors are disposed opposite each other in the stacking direction of the magnetic layers, and the base body includes, as viewed from the extension direction of the coil conductors, a first portion disposed between adjacent coil conductors in the stacking direction and covering the corners of at least some of the coil conductors, and a second portion surrounding the coil conductor, and the average particle size of the metal magnetic particles located in the first portion is smaller than the average particle size of the metal magnetic particles located in the second portion.

[0007] In a coil component according to one aspect of the present invention, the average particle size of the metal magnetic particles located in the first portion is smaller than the average particle size of the metal magnetic particles located in the second portion. This reduces the magnetic permeability around the corners of the coil conductor in the coil component. Therefore, the coil component has high magnetic resistance around the corners of the coil conductor, thereby preventing magnetic flux from concentrating at the corners of the coil conductor and preventing magnetic saturation at the corners. This improves the DC bias characteristics of the coil component. As a result, the coil component reduces loss.

[0008] (2) In the coil component of (1) above, the element body includes a third portion, which, when viewed from the extension direction of the coil conductor, is located opposite the first portion so as to sandwich the coil conductor between the first portion and the third portion in the stacking direction, and the average particle size of the metal magnetic particles located in the third portion may be smaller than the average particle size of the metal magnetic particles located in the second portion. In this configuration, the coil conductor is located between the first portion and the third portion. This reduces the magnetic permeability around the coil conductor in the coil component. Therefore, in the coil component, magnetic resistance is increased around the coil conductor, thereby suppressing magnetic flux concentration in the coil conductor and preventing magnetic saturation. Therefore, the coil component can improve DC bias characteristics, thereby further reducing loss.

[0009] (3) In the coil component of (1) or (2), the coil conductor may have four side surfaces, and the first portion may be disposed so as not to cover at least a portion of each of the four side surfaces. In this configuration, at least a portion of the area surrounding the coil conductor is covered with a metallic magnetic material having a large average particle size, thereby ensuring magnetic permeability. Therefore, the coil component can ensure inductance, thereby ensuring coil characteristics.

[0010] (4) In any one of the coil components (1) to (3) above, the first portion may be provided in a layered shape having a thickness in the stacking direction, and the thickness of the first portion in the stacking direction may be smaller than the thickness of the coil conductor in the stacking direction. In this configuration, since the first portion is layered, the first portion is reliably provided between adjacent coil conductors. Furthermore, since the thickness of the first portion in the stacking direction is smaller than the thickness of the coil conductor in the stacking direction, magnetic saturation at the corners of the coil conductor can be suppressed while ensuring magnetic permeability. Therefore, the coil component can ensure inductance and therefore coil characteristics.

[0011] (5) In any one of the coil components (1) to (4) above, the first portions may be provided between all of the coil conductors that are adjacent to each other in the stacking direction. With this configuration, since the first portions are provided between all of the coil conductors that are adjacent to each other, it is possible to prevent magnetic flux from concentrating at the corners of all of the coil conductors, thereby preventing magnetic saturation from occurring at the corners. Therefore, the DC bias characteristics of the coil component can be further improved.

[0012] (6) In the coil component of any one of (1) to (5), the first portion may be provided along a corner of the coil conductor, and at least some of the metal magnetic particles located in the first portion may be in contact with the coil conductor. With this configuration, no other member is provided between the first portion and the corner of the coil conductor, so that concentration of magnetic flux at the corner of the coil conductor can be more reliably suppressed. [Effects of the Invention]

[0013] According to one aspect of the present invention, loss can be reduced. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view of a coil component according to one embodiment. [Figure 2] FIG. 2 is a diagram showing a cross-sectional configuration of the coil component shown in FIG. [Figure 3] FIG. 3 is a perspective view showing the configuration of the coil. [Figure 4] FIG. 4 is a schematic diagram showing an enlarged cross-sectional configuration between coil conductors in the element body. [Figure 5] FIG. 5 is a schematic diagram showing an enlarged cross-sectional configuration of a coil conductor in the element body. [Figure 6] FIG. 6 is a diagram showing a cross-sectional configuration of a coil component according to another embodiment. [Figure 7] FIG. 7 is a diagram showing a cross-sectional configuration of a coil component according to another embodiment. [Figure 8]FIG. 8 is a diagram showing a cross-sectional configuration of a coil component according to another embodiment. [Figure 9] FIG. 9 is a diagram showing a cross-sectional configuration of a coil component according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or corresponding elements are designated by the same reference numerals, and redundant description will be omitted.

[0016] As shown in FIGS. 1 and 2, the coil component 1 includes an element body 2, and a terminal electrode 4 and a terminal electrode 5 disposed on both ends of the element body 2, respectively.

[0017] The element body 2 has a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape with chamfered corners and ridges, and a rectangular parallelepiped shape with rounded corners and ridges. The element body 2 has, as its outer surfaces, a pair of end faces 2a, 2b facing each other, a pair of main faces 2c, 2d facing each other, and a pair of side faces 2e, 2f facing each other. The facing direction in which the pair of main faces 2c, 2d face each other is the first direction D1. The facing direction in which the pair of end faces 2a, 2b face each other is the second direction D2. The facing direction in which the pair of side faces 2e, 2f face each other is the third direction D3. In this embodiment, the first direction D1 is the height direction of the element body 2. The second direction D2 is the longitudinal direction of the element body 2 and is perpendicular to the first direction D1. The third direction D3 is the width direction of the element body 2 and is perpendicular to the first direction D1 and the second direction D2.

[0018] The pair of end faces 2a, 2b extend in a first direction D1 to connect the pair of principal faces 2c, 2d together. The pair of end faces 2a, 2b also extend in a third direction D3 (the direction of the short sides of the pair of principal faces 2c, 2d). The pair of side faces 2e, 2f extend in the first direction D1 to connect the pair of principal faces 2c, 2d together. The pair of side faces 2e, 2f also extend in a second direction D2 (the direction of the long sides of the pair of end faces 2a, 2b). The principal face 2d can be defined as a mounting surface that faces another electronic device (for example, a circuit board or a multilayer electronic component) when the coil device 1 is mounted on the other electronic device.

[0019] As shown in FIG. 3, the element body 2 is constructed by stacking multiple magnetic layers 6. Each magnetic layer 6 is stacked in a first direction D1. That is, the first direction D1 is the stacking direction. The element body 2 has multiple stacked magnetic layers 6. In an actual element body 2, the multiple magnetic layers 6 are integrated to the extent that the boundaries between the layers are not visible.

[0020] The base body 2 (magnetic layer 6) includes a plurality of metal magnetic particles P (see FIG. 4). The metal magnetic particles P are made of a soft magnetic alloy (soft magnetic material). The soft magnetic alloy is, for example, an Fe-Si alloy. When the soft magnetic alloy is an Fe-Si alloy, it may also include P. The soft magnetic alloy may also be, for example, an Fe-Ni-Si-M alloy. "M" includes one or more elements selected from Co, Cr, Mn, P, Ti, Zr, Hf, Nb, Ta, Mo, Mg, Ca, Sr, Ba, Zn, B, Al, and rare earth elements.

[0021] In the element body 2, the metal magnetic particles P, P are bonded to each other. The bond between the metal magnetic particles P, P is realized, for example, by bonding between oxide films formed on the surfaces of the metal magnetic particles P. The thickness of the oxide film is, for example, not less than 5 nm and not more than 60 nm. The oxide film may be composed of one or more layers.

[0022] As shown in FIGS. 1 and 2, the terminal electrode 4 is disposed on the end face 2a side of the element body 2, and the terminal electrode 5 is disposed on the end face 2b side of the element body 2. That is, the terminal electrodes 4 and 5 are positioned apart from each other in the opposing direction of the pair of end faces 2a, 2b. The terminal electrodes 4 and 5 contain a conductive material (such as Ag or Pd). The terminal electrodes 4 and 5 are formed as a sintered body of a conductive paste containing a conductive metal powder (such as Ag powder or Pd powder) and glass frit. The terminal electrodes 4 and 5 are electroplated to form a plating layer on their surfaces. For example, Ni, Sn, etc. are used for the electroplating.

[0023] The terminal electrode 4 is disposed on one end face 2a. The terminal electrode 4 includes five electrode portions: a first electrode portion 4a located on the end face 2a, a second electrode portion 4b located on the principal face 2c, a third electrode portion 4c located on the principal face 2d, a fourth electrode portion 4d located on the side face 2e, and a fifth electrode portion 4e located on the side face 2f. The first electrode portion 4a, the second electrode portion 4b, the third electrode portion 4c, the fourth electrode portion 4d, and the fifth electrode portion 4e are connected at the ridges of the element body 2 and are electrically connected to one another. The terminal electrode 4 is formed on five surfaces: the end face 2a, the pair of principal faces 2c and 2d, and the pair of side faces 2e and 2f. The first electrode portion 4a, the second electrode portion 4b, the third electrode portion 4c, the fourth electrode portion 4d, and the fifth electrode portion 4e are integrally formed.

[0024] In this embodiment, the edges of the second electrode portion 4b and the third electrode portion 4c of the terminal electrode 4 extend along, for example, the third direction D3. The edge of the second electrode portion 4b is formed linearly on the main surface 2c. The edge of the third electrode portion 4c is formed linearly on the main surface 2d. The edges of the fourth electrode portion 4d and the fifth electrode portion 4e of the terminal electrode 4 extend along the first direction D1. The edge of the fourth electrode portion 4d is formed linearly on the side surface 2e. The edge of the fifth electrode portion 4e is formed linearly on the side surface 2f. The edges of the second electrode portion 4b, the third electrode portion 4c, the fourth electrode portion 4d, and the fifth electrode portion 4e may each be curved or uneven.

[0025] The terminal electrode 5 is disposed on the other end face 2b side. The terminal electrode 5 includes five electrode portions: a first electrode portion 5a located on the end face 2b, a second electrode portion 5b located on the principal face 2c, a third electrode portion 5c located on the principal face 2d, a fourth electrode portion 5d located on the side face 2e, and a fifth electrode portion 5e located on the side face 2f. The first electrode portion 5a, the second electrode portion 5b, the third electrode portion 5c, the fourth electrode portion 5d, and the fifth electrode portion 5e are connected at the ridges of the element body 2 and are electrically connected to one another. The terminal electrode 5 is formed on five surfaces: the one end face 2b, the pair of principal faces 2c and 2d, and the pair of side faces 2e and 2f. The first electrode portion 5a, the second electrode portion 5b, the third electrode portion 5c, the fourth electrode portion 5d, and the fifth electrode portion 5e are integrally formed.

[0026] In this embodiment, the edges of the second electrode portion 5b and the third electrode portion 5c of the terminal electrode 5 extend along, for example, the third direction D3. The edge of the second electrode portion 5b is formed linearly on the main surface 2c. The edge of the third electrode portion 5c is formed linearly on the main surface 2d. The edges of the fourth electrode portion 5d and the fifth electrode portion 5e of the terminal electrode 5 extend along the first direction D1. The edge of the fourth electrode portion 5d is formed linearly on the side surface 2e. The edge of the fifth electrode portion 5e is formed linearly on the side surface 2f. The edges of the second electrode portion 5b, the third electrode portion 5c, the fourth electrode portion 5d, and the fifth electrode portion 5e may each be curved or uneven.

[0027] As shown in Fig. 2, the coil component 1 includes a coil 8. The coil 8 is disposed within the element body 2. The coil 8 is configured in a spiral shape by electrically connecting a plurality of coil conductors CC to a first connecting conductor 18 and a second connecting conductor 19. In this embodiment, as shown in Fig. 3, the plurality of coil conductors CC include a plurality of coil conductors 10, 11, 12, 13, 14, 15, 16, and 17.

[0028] The coil conductor 10 and the first connecting conductor 18 are integrally formed. The coil conductor 17 and the second connecting conductor 19 are integrally formed. Adjacent coil conductors CC (coil conductors 10 to 17) are electrically connected by through-hole conductors (not shown). The first connecting conductor 18 constitutes one end of the coil 8. The first connecting conductor 18 is exposed at the end surface 2a of the element body 2 and connected to the terminal electrode 4 (first electrode portion 4a). The second connecting conductor 19 constitutes the other end of the coil 8. The second connecting conductor 19 is exposed at the end surface 2b of the element body 2 and connected to the terminal electrode 5 (first electrode portion 5a).

[0029] The coil conductors CC (coil conductors 10-17), the first connecting conductor 18, and the second connecting conductor 19 are made of a conductive material typically used as a coil conductor. Examples of conductive materials that can be used include Ag, Cu, Au, Al, Pd, and Pd / Ag alloys. In this embodiment, the conductive material is Ag. The coil conductors CC (coil conductors 10-17), the first connecting conductor 18, and the second connecting conductor 19 are plated conductors. The coil conductors CC (coil conductors 10-17), the first connecting conductor 18, and the second connecting conductor 19 may be formed as a sintered body of a conductive paste containing the above-mentioned conductive material.

[0030] As shown in FIG. 2, the multiple coil conductors CC have portions that face each other in the first direction D1. Specifically, coil conductor 10 and coil conductor 11 have portions that face each other in the first direction D1. Coil conductor 11 and coil conductor 12 have portions that face each other in the first direction D1. Coil conductor 12 and coil conductor 13 have portions that face each other in the first direction D1. Coil conductor 13 and coil conductor 14 have portions that face each other in the first direction D1. Coil conductor 14 and coil conductor 15 have portions that face each other in the first direction D1. Coil conductor 15 and coil conductor 16 have portions that face each other in the first direction D1. Coil conductor 16 and coil conductor 17 have portions that face each other in the first direction D1.

[0031] Each of the multiple coil conductors CC (coil conductors 10 to 17) has a rectangular shape in a cross section perpendicular to the extension direction. A rectangular shape can include not only a shape with right angles but also a shape with curved corners. Each of the multiple coil conductors CC (coil conductors 10 to 17) has corners C1, C2, C3, and C4 (see FIG. 4) in a cross section perpendicular to the extension direction.

[0032] 4 is a schematic diagram showing an enlarged cross-sectional configuration between coil conductors CC in the element body 2. As shown in FIG. 4, the coil conductor CC has four side surfaces S1, S2, S3, and S4. Side surface S1 and side surface S2 face each other in the first direction D1. Side surface S3 and side surface S4 each extend along the first direction D1 between side surface S1 and side surface S2.

[0033] The coil conductor CC has four corners C1, C2, C3, and C4. Corner C1 is formed by side surface S1 and side surface S3. Corner C2 is formed by side surface S1 and side surface S4. Corner C3 is formed by side surface S2 and side surface S3. Corner C4 is formed by side surface S2 and side surface S4.

[0034] 2, 4, or 5, the element body 2 includes a first portion A1, a second portion A2, and a third portion A3. When viewed from the extension direction of the coil conductors CC (third direction D3 in the example shown in FIG. 2), the first portion A1 is provided between adjacent coil conductors CC in the first direction D1, and covers corners C1 and C2 of the coil conductors CC. In the example shown in FIG. 2, the first portion A1 is provided so as to also cover the first connecting conductor 18 and the second connecting conductor 19.

[0035] As shown in FIG. 4, the first portion A1 is provided to cover the side surface S1, the corner C1, and the corner C2. The first portion A1 is provided to cover the side surface S1, a portion of the side surface S3, and a portion of the side surface S4. The first portion A1 is provided to follow the coil conductor CC. At least some of the multiple metal magnetic particles P1 located in the first portion A1 are in contact with the coil conductor CC. In other words, no other members are provided between the coil conductor CC and the first portion A1. Multiple metal magnetic particles P1 are arranged in the first portion A1. The first portion A1 is configured to include multiple metal magnetic particles P1.

[0036] The second portion A2 is a portion surrounding the coil conductor CC (a portion other than the first portion A1 and the third portion A3). A plurality of metal magnetic particles P2 are arranged in the second portion A2. The second portion A2 is configured to include a plurality of metal magnetic particles P2.

[0037] 2 and 5, the third portion A3 is provided at a position sandwiching the coil conductor CC with the first portion A1 in the first direction D1 when viewed from the extension direction of the coil conductor CC. The first portion A1 and the third portion A3 are provided at positions sandwiching the coil conductor CC. In other words, the coil conductor CC is located between the first portion A1 and the third portion A3. A plurality of metal magnetic particles P3 are arranged in the third portion A3. The third portion A3 is configured to include a plurality of metal magnetic particles P3.

[0038] The average particle size of the metal magnetic particles P1 located in the first portion A1 is smaller than the average particle size of the metal magnetic particles P2 located in the second portion A2. The average particle size of the metal magnetic particles P3 located in the third portion A3 is smaller than the average particle size of the metal magnetic particles P2 located in the second portion A2. The average particle size of the metal magnetic particles P3 may be equal to or larger than the average particle size of the metal magnetic particles P1. In this embodiment, the particle size is defined as the circle-equivalent diameter. The circle-equivalent diameters of the metal magnetic particles P1, P2, and P3 can be obtained, for example, as follows.

[0039] A cross-sectional photograph of the coil component 1 is obtained. The obtained cross-sectional photograph is subjected to image processing using software. The boundaries of the metal magnetic particles P1, P2, and P3 are identified through image processing, and the areas of the metal magnetic particles P1, P2, and P3 are determined. From the determined areas of the metal magnetic particles P1, P2, and P3, the particle diameters converted into circle-equivalent diameters are determined. Here, the particle diameters of 100 or more metal magnetic particles P1, P2, and P3 are calculated, and the particle size distribution of these metal magnetic particles P1, P2, and P3 is determined. The particle diameter (d50) at 50% of the cumulative value in the determined particle size distribution is defined as the "average particle diameter." There are no particular restrictions on the particle shape of the metal magnetic particles P1, P2, and P3.

[0040] As described above, in the coil component 1 according to this embodiment, the average particle size of the metal magnetic particles P1 located in the first portion A1 is smaller than the average particle size of the metal magnetic particles P2 located in the second portion A2. As a result, in the coil component 1, the magnetic permeability around the corners C1 and C2 of the coil conductor CC is low. Therefore, in the coil component 1, the magnetic resistance is high around the corners C1 and C2 of the coil conductor CC, which prevents magnetic flux from concentrating at the corners C1 and C2 of the coil conductor CC and prevents magnetic saturation from occurring at the corners C1 and C2. Therefore, the coil component 1 improves the DC bias characteristics. As a result, the coil component reduces loss.

[0041] In the coil component 1 according to this embodiment, the element body 2 includes a third portion A3 disposed at a position sandwiching the coil conductor CC from the first portion A1 in the first direction D1, as viewed from the extension direction of the coil conductor CC. In the coil component 1, the average particle size of the metal magnetic particles P3 located in the third portion A3 is smaller than the average particle size of the metal magnetic particles P2 located in the second portion A2. In this configuration, the coil conductor CC is located between the first portion A1 and the third portion A3. This reduces the magnetic permeability around the coil conductor CC in the coil component 1. Therefore, in the coil component 1, magnetic resistance is increased around the coil conductor CC, thereby suppressing magnetic flux concentration in the coil conductor CC and preventing magnetic saturation. Therefore, the coil component 1 improves DC bias characteristics, thereby further reducing loss.

[0042] In the coil component 1 according to this embodiment, the first portions A1 are provided between all of the coil conductors CC that are adjacent to each other in the first direction D1. In this configuration, the first portions A1 are provided between all of the coil conductors CC that are adjacent to each other, which prevents magnetic flux from concentrating at the corners C1 and C2 of the corresponding coil conductors CC, thereby preventing magnetic saturation from occurring at the corners C1 and C2. Therefore, the coil component 1 can further improve the DC bias characteristics.

[0043] In the coil component 1 according to this embodiment, the first part A1 is provided along the corner parts C1 and C2 of the coil conductor CC. At least a part of the plurality of metal magnetic particles P1 located in the first part A1 is in contact with the coil conductor CC. In this configuration, since no other member is provided between the first part A1 and the corner parts C1 and C2 of the coil conductor CC, it is possible to more reliably suppress the concentration of magnetic flux at the corner parts C1 and C2 of the coil conductor CC.

[0044] As described above, the embodiments of the present invention have been described. However, the present invention is not necessarily limited to the above-described embodiments, and various modifications can be made without departing from the gist thereof.

[0045] In the above embodiment, an example in which the first part A1 covers the corner parts C1 and C2 and the side surface S1 of the coil conductor CC has been described. However, the first part A1 only needs to cover a part of the corner parts C1 and C2 of the coil conductor CC.

[0046] As shown in FIG. 6, the first part A1 is provided so as to cover the corner parts C1 and C2 of the coil conductor CC. That is, in the example shown in FIG. 5, the first part A1 is not provided so as to cover the side surface S1 of the coil conductor CC.

[0047] As shown in FIG. 7, the first part A1 may be provided in a layered form having a thickness in the first direction D1. In this configuration, since the first part A1 is layered, the first part A1 is surely provided between the coil conductors CC adjacent to each other. The third part A3 may also be provided in a layered form. The thickness T1 of the first part A1 in the first direction D1 is smaller than the thickness T2 of the coil conductor CC in the first direction D1 (T1 < T2). In this configuration, it is possible to ensure the magnetic permeability while suppressing the occurrence of magnetic saturation at the corner parts C1 and C2 of the coil conductor CC. Therefore, in the coil component 1, since the inductance can be ensured, the coil characteristics can be ensured.

[0048] 8, the layered first portion A1 may be provided in a portion of the coil device 1. As shown in Fig. 9, the first portion A1 covers only a portion of the corners C1 and C2 of the coil conductor CC, and the layered first portion A1 may be provided in a portion of the coil device 1.

[0049] In the above embodiment, the coil conductor CC and the like are made of Ag as a conductive material. However, the coil conductor CC may be a plated conductor.

[0050] In the above embodiment, the terminal electrode 4 has the first electrode portion 4a, the second electrode portion 4b, the third electrode portion 4c, the fourth electrode portion 4d, and the fifth electrode portion 4e, and the terminal electrode 5 has the first electrode portion 5a, the second electrode portion 5b, the third electrode portion 5c, the fourth electrode portion 5d, and the fifth electrode portion 5e. However, the shape of the terminal electrode is not limited to this. For example, the terminal electrode may be disposed only on the main surface 2d (bottom terminal type), or may be disposed across the end surfaces 2a, 2b and the main surface 2d (L-shaped terminal type). [Explanation of symbols]

[0051] 1...coil component, 2...element body, 6...magnetic layer, 8...coil, 10, 11, 12, 13, 14, 15, 16, 17...coil conductor, A1...first portion, A2...second portion, A3...third portion, C1, C2, C3, C4...corner portion, CC...coil conductor, P...metal magnetic particle, P1, P2, P3...metal magnetic particle, S1, S2, S3, S4...side surface.

Claims

1. an element body formed by laminating a plurality of magnetic layers each containing a plurality of metal magnetic particles of a soft magnetic material; a coil disposed within the element body and composed of a plurality of coil conductors; Each of the plurality of coil conductors has a rectangular shape and corners in a cross section perpendicular to the extending direction of the coil conductor, At least some of the coil conductors are arranged opposite to each other in the stacking direction of the magnetic layers, When viewed from the extending direction of the coil conductor, the element body has a first portion provided between the coil conductors adjacent to each other in the stacking direction and covering at least a corner of the coil conductor; a second portion of the periphery of the coil conductor; A coil component, wherein the average particle size of the metal magnetic particles located in the first portion is smaller than the average particle size of the metal magnetic particles located in the second portion.

2. the element body includes a third portion, the third portion is provided at a position facing the first portion so as to sandwich the coil conductor between the first portion and the third portion in the stacking direction, as viewed from the extending direction of the coil conductor, The coil component according to claim 1 , wherein an average particle size of the metal magnetic particles located in the third portion is smaller than an average particle size of the metal magnetic particles located in the second portion.

3. the coil conductor has four sides; The coil component according to claim 1 or 2, wherein the first portion is provided so as not to cover at least a portion of each of the four side surfaces.

4. the first portion is provided in a layer shape having a thickness in the stacking direction, The coil component according to claim 1 , wherein a thickness of the first portion in the stacking direction is smaller than a thickness of the coil conductor in the stacking direction.

5. The coil component according to claim 1 , wherein the first portions are provided between all of the coil conductors that are adjacent to each other in the stacking direction.

6. the first portion is provided along the corner of the coil conductor, The coil component according to claim 1 , wherein at least some of the plurality of metal magnetic particles located in the first portion are in contact with the coil conductor.

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