Inductor component

Abstract

The inductor component is provided with: a green body; the coil is arranged in the blank body; and a first external electrode and a second external electrode provided on the body and electrically connected to the coil, the coil having a winding portion wound in a spiral shape in the direction of the axis, the coil having: the winding portion; and a first lead-out wire and a second lead-out wire connecting one end and the other end of the winding portion to the first external electrode and the second external electrode, at least one of the first external electrode and the second external electrode having an embedded portion embedded in the green body. At least one of the first lead-out wiring and the second lead-out wiring has: a connection portion connected to the winding portion; a bent portion bent from the connection portion toward the embedded portion has a concave shape when viewed from the direction of the axis, a length L1 of the bent portion on a contact surface between the embedded portion and the lead-out wiring is greater than a wiring width W1 of the connection portion, and the length L1 is greater than a height D1 of the embedded portion in a direction perpendicular to the contact surface.

Description

Technical Field

[0001] The present invention relates to inductor components. Background Art

[0002] Conventionally, as an inductor component, there is an inductor component described in Japanese Patent Application Publication No. 2017-11044 (Patent Document 1). The inductor component includes: a body; a coil provided in the body; and a first external electrode and a second external electrode provided in the body and electrically connected to the coil, and the coil includes: a winding portion; and a first lead wiring and a second lead wiring, and one end and the other end of the winding portion are connected to the first external electrode and the second external electrode.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2017-011044

[0004] In conventional inductor components, as a countermeasure against cracks, the firing residual stress generated at the interface between the external electrode and the green body is reduced. In order to reduce the firing residual stress, in conventional inductor components, the volume of the external electrode is reduced and the wiring width of the lead wiring is reduced. However, in conventional inductor components, current sometimes concentrates on the contact surface between the lead wiring and the external electrode, causing the contact surface to heat up. Summary of the invention

[0005] The present disclosure provides an inductor component that suppresses heat generation in a contact surface between a coil and an external electrode.

[0006] In order to solve the above-mentioned problems, an inductor component according to one embodiment of the present disclosure includes:

[0007] green body;

[0008] A coil is disposed in the blank; and

[0009] The first external electrode and the second external electrode are provided on the above-mentioned body and are electrically connected to the above-mentioned coil.

[0010] The coil has a winding portion wound in a spiral shape along an axial direction.

[0011] The coil comprises: the winding portion; and a first lead wiring and a second lead wiring connecting one end and the other end of the winding portion to the first external electrode and the second external electrode,

[0012] At least one of the first external electrode and the second external electrode has an embedded portion embedded in the body.

[0013] At least one of the first lead wiring and the second lead wiring has: a connection portion connected to the winding portion; and a bent portion bent from the connection portion toward the embedded portion.

[0014] When viewed from the direction of the above axis,

[0015] The bent portion has a concave shape, and a length dimension L1 of the bent portion on a contact surface between the embedded portion and the lead wiring is larger than a wiring width W1 of the connecting portion.

[0016] The length dimension L1 is larger than a height dimension D1 of the embedded portion in a direction perpendicular to the contact surface.

[0017] By making the length dimension L1 of the contact surface between the bent portion and the embedded portion larger than the wiring width W1 of the connection portion, the contact surface between the bent portion and the embedded portion becomes larger, and the amount of current flowing per unit area can be reduced. As a result, the heat generated in the contact surface between the bent portion and the embedded portion can be diffused, and the temperature rise in the contact surface can be suppressed.

[0018] According to the inductor component of one embodiment of the present disclosure, it is possible to suppress heat generation at the contact surface between the coil and the external electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a perspective view showing a first embodiment of the inductor component.

[0020] Figure 2 This is a perspective front view seen from the first side surface of the first embodiment.

[0021] Figure 3 This is an exploded view of the first embodiment.

[0022] Figure 4 This is a perspective front view seen from the first side surface of the second embodiment.

[0023] Figure 5 It is an exploded view of the second embodiment.

[0024] Figure 6 This is a perspective front view seen from the first side surface of the third embodiment.

[0025] Figure 7 It is an exploded view of the third embodiment.

[0026] Figure 8 This is a perspective front view seen from the top surface side in the fourth embodiment.

[0027] Fig.9A It is an exploded view of the fourth embodiment.

[0028] Fig. 9B It is an exploded view of the fourth embodiment.

[0029] Fig. 9C It is an exploded view of the fourth embodiment.

[0030] Explanation of reference numerals: 1, 1A, 1B, 1C…inductor component; 10…blank; 11…insulating layer; 13…first side surface; 14…second side surface; 15…first end surface; 16…second end surface; 17…bottom surface; 18…top surface; 20, 20A, 20B, 20C…coil; 20a, 20b, 20aB, 20bB, 20aC, 20bC…outer peripheral surface; 201-204, 201A, 202A, 201B-204B, 201C-212C…coil wiring; 21, 22, 21A, 22A, 21B, 22B, 21C, 22C…lead-out wiring; 211, 211A, 211B, 211C…connecting portion ; 212, 212A, 212B, 212C…bending portion; 23, 23A, 23B, 23C…winding portion; 24…pad portion; 30, 30A, 30B, 30C…first external electrode; 40, 40A, 40B, 40C…second external electrode; 31, 32, 41, 42, 31B, 41B, 31C, 41C…buried portion; 33, 43…plating; 601~603, 601A, 601B~603B, 601C~611C…via wiring; D1, D2, D3, D4…height dimension; L, L1, L2, L3…length dimension; W1…wiring width of the connecting portion; a1, a2, a3…contact point. DETAILED DESCRIPTION

[0031] Hereinafter, an inductor unit as one embodiment of the present disclosure will be described in detail by way of the illustrated embodiment. Note that the drawings are partially schematic and may not reflect actual dimensions or ratios.

[0032] <First embodiment>

[0033] Figure 1 It is a perspective view showing a first embodiment of the inductor component. Figure 2 This is a perspective front view of the inductor component as seen from the first side surface. Figure 3 is an exploded view of the inductor components.

[0034] like Figures 1 to 3 As shown, the inductor component 1 comprises: a body 10; a coil 20 provided on the body 10; and a first external electrode 30 and a second external electrode 40 provided on the body 10 and electrically connected to the coil 20. Figure 2In the figure, the body and the coil are depicted transparently to make the structure easy to understand, but they may be semi-transparent or opaque.

[0035] The inductor component 1 is electrically connected to wiring of a circuit substrate (not shown) via the first and second external electrodes 30 and 40. The inductor component 1 is used, for example, as an impedance matching coil (matching coil) for a high-frequency circuit, and is used in electronic devices such as personal computers, DVD players, digital cameras, TVs, mobile phones, automotive electronics, and medical / industrial machinery. However, the use of the inductor component 1 is not limited to this, and for example, it can also be used in a tuning circuit, a filter circuit, a rectifier smoothing circuit, etc.

[0036] The blank 10 is formed in a substantially rectangular parallelepiped shape. The blank 10 includes: a first side surface 13 and a second side surface 14 facing each other; a first end surface 15 and a second end surface 16 facing each other; a bottom surface 17 connected between the first side surface 13 and the second side surface 14 and between the first end surface 15 and the second end surface 16; and a top surface 18 facing the bottom surface 17. That is, the outer surface of the blank 10 is composed of the first side surface 13, the second side surface 14, the first end surface 15, the second end surface 16, the bottom surface 17, and the top surface 18.

[0037] In addition, if Figure 1 As shown, the X direction is a direction orthogonal to the first end face 15 and the second end face 16 and from the first end face 15 to the second end face 16. The Y direction is a direction orthogonal to the first side face 13 and the second side face 14 and from the second side face 14 to the first side face 13. The Z direction is a direction orthogonal to the bottom face 17 and the top face 18 and from the bottom face 17 to the top face 18. The X direction is also referred to as the length direction of the blank 10, the Y direction is also referred to as the width direction of the blank 10, and the Z direction is also referred to as the height direction of the blank 10. The X direction, the Y direction, and the Z direction are mutually orthogonal directions, and when arranged in the order of X, Y, and Z, they form a left-hand system.

[0038] like Figure 3 As shown, a plurality of insulating layers 11 are stacked to form the body 10. Specifically, a plurality of insulating layers 11 are stacked from the second side surface 14 toward the first side surface 13 to form the body 10. In addition, the number of insulating layers 11 is not limited to Figure 3 In addition, in the present application, stacking is not limited to the stacking direction during manufacturing, but also includes the opposite direction. Figure 3 In the figure, the layers are stacked from the upper left to the lower right. The layers are stacked in the same way in other exploded views.

[0039] The insulating layer 11 is made of a magnetic material or a non-magnetic material. As a magnetic material, there are ferrites, etc., and as a non-magnetic material, there are glasses such as borosilicate glass, aluminum oxide, resins, etc. A plurality of insulating layers 11 are stacked in the Y direction. The insulating layer 11 is a layer extending in the XZ plane orthogonal to the stacking direction in the Y direction. The thickness of the insulating layer 11 is not particularly limited, and for example, the thickness is the same. In addition, the interfaces between two adjacent insulating layers 11 are sometimes unclear due to firing, etc. of the plurality of insulating layers 11. In addition, the thickness of the insulating layer 11 may also be different. For example, the insulating layer 11 corresponding to the second side 14 and the insulating layer 11 corresponding to the first side 13 may be thicker than the other insulating layers 11, or thinner than the other insulating layers 11.

[0040] The first external electrode 30 is formed in an L shape from the first end surface 15 to the bottom surface 17. The first external electrode 30 includes: a first embedded portion 31 provided in the body 10 and extending along the first end surface 15; a second embedded portion 32 provided in the body 10 and connected to the first embedded portion 31 and extending along the bottom surface 17; and a first plating layer 33 located on the surface of the body 10 and formed on the surfaces of the first and second embedded portions 31 and 32.

[0041] The first and second embedded portions 31 and 32 may be made of, for example, a conductive material such as Ag, Cu, Au, or glass particles, or may be formed of the same material as the coil 20 .

[0042] The first plating layer 33 is provided on the first and second embedded portions 31 and 32 and has an L shape. The first plating layer 33 rises from the surface of the body 10. In addition, the first plating layer 33 may be partially or entirely embedded in the body 10.

[0043] The first plating layer 33 is formed by plating Ni, Sn, Au, Cu, etc. For example, the first and second embedded parts 31 and 32 have Ni plating layers, and the Ni plating layers have Sn plating layers. Figure 1 as well as Figure 2 As shown, in the first end surface 15, the height of the first plating layer 33 in the Z-axis direction is greater than the height of the first embedded portion 31 in the Z-axis direction. In the bottom surface 17, the length of the first plating layer 33 in the X-axis direction is greater than the length of the second embedded portion 32 in the X-axis direction. In addition, the height of the first plating layer 33 in the Z-axis direction may be smaller than the height of the first embedded portion 31 in the Z-axis direction, or they may be the same height. The length of the first plating layer 33 in the X-axis direction may be smaller than the length of the second embedded portion 32 in the X-axis direction, or they may be the same length.

[0044] The second external electrode 40 is formed in an L shape from the second end surface 16 to the bottom surface 17. The second external electrode 40 includes: a first embedded portion 41 provided in the body 10 and extending along the second end surface 16; a second embedded portion 42 provided in the body 10 and connected to the first embedded portion 41 and extending along the bottom surface 17; and a second plating layer 43 located on the surface of the body 10 and formed on the surfaces of the first and second embedded portions 41 and 42.

[0045] The first and second embedded portions 41 and 42 may be made of, for example, a conductive material such as Ag, Cu, Au, or glass particles, or may be formed of the same material as the coil 20 .

[0046] The first plating layer 43 is provided on the first and second embedded portions 41 and 42 and is L-shaped. The first plating layer 43 protrudes from the surface of the blank 10. In addition, the first plating layer 43 may be partially embedded in the interior of the blank 10, or may be fully embedded in the interior of the blank 10. In addition, the plating layer refers to a layer including a plating film.

[0047] The first plating layer 43 is formed by plating Ni, Sn, Au, Cu, etc. For example, the first and second embedded parts 41 and 42 have Ni plating layers, and the Ni plating layers have Sn plating layers. Figure 1 as well as Figure 2 As shown, in the second end surface 16, the height of the second plating layer 43 in the Z-axis direction is greater than the height of the first embedded portion 41 in the Z-axis direction. In the bottom surface 17, the length of the second plating layer 43 in the X-axis direction is greater than the length of the second embedded portion 42 in the X-axis direction. In addition, the height of the second plating layer 43 in the Z-axis direction may be smaller than the height of the first embedded portion 41 in the Z-axis direction, or they may be the same height. The length of the second plating layer 43 in the X-axis direction may be smaller than the length of the second embedded portion 42 in the X-axis direction, or they may be the same length.

[0048] like Figure 3As shown, the first and second embedded portions 31, 32 have a structure in which a plurality of first external electrode conductor layers 35 embedded in the base body 10 are stacked in surface contact. The first and second embedded portions 41, 42 have a structure in which a plurality of second external electrode conductor layers 45 embedded in the base body 10 are stacked in surface contact. The first external electrode conductor layer 35 extends along the first end surface 15 and the bottom surface 17, and the second external electrode conductor layer 45 extends along the second end surface 16 and the bottom surface 17. By providing the embedded portions 31, 32, 41, 42 in the base body 10, the inductor component 1 can be miniaturized. In addition, the coil 20 and the embedded portions 31, 32, 41, 42 can be formed by the same process, and the variation in the positional relationship between the coil 20 and the first and second external electrodes 30, 40 can be reduced, thereby reducing the variation in the electrical characteristics of the inductor component 1. In addition, a part of the external electrode conductor layers 35 and 45 may be embedded in the green body 10, and the other part may be formed on the outer surface of the green body 10, or the entire external electrode conductor layers 35 and 45 may be formed on the outer surface of the green body 10. Figure 3 In the figure, the first and second plating layers 33 and 43 are not described.

[0049] The coil 20 has an outer peripheral surface 20a on the side of the axis AX, i.e., the inner diameter side, and an outer peripheral surface 20b on the outer diameter side opposite to the inner diameter. The coil 20 has a spiral structure in which the axis AX is parallel to the bottom surface 17 of the blank 10 and is wound along the axis while crossing the first side surface 13 and the second side surface 14 of the blank 10. The axis of the coil is parallel to the Y direction. The coil 20 contains Ag. In addition, the coil 20 may also contain a conductive material other than Ag (for example, Cu, Au, etc.) or glass.

[0050] The coil 20 is formed into a roughly rectangular shape when viewed from the direction of the axis AX, but is not limited to this shape. The shape of the coil 20 may also be, for example, circular, elliptical, rectangular, or other polygonal shapes. The direction of the axis of the coil 20 refers to a direction parallel to the central axis of the spiral around which the coil 20 is wound. The direction of the axis of the coil 20 is the same direction as the stacking direction of the insulating layer 11. The "parallel" in this application is not limited to a strict parallel relationship, but also includes a substantial parallel relationship taking into account the range of realistic deviations.

[0051] The coil 20 includes a winding portion 23, a first lead wiring 21 located between a first end of the winding portion 23 and a first external electrode 30, and a second lead wiring 22 located between a second end of the winding portion 23 and a second external electrode 40. In the present embodiment, the winding portion 23 is integrated with the first and second lead wirings 21 and 22, and there is no clear boundary, but the present invention is not limited thereto, and the winding portion and the lead wiring may be formed by different types of materials and different types of methods, so that there is a boundary.

[0052] The winding portion 23 is wound into a spiral shape along the axis AX. That is, the winding portion 23 refers to the portion of the spiral shape in which the coil 20 overlaps each other when viewed from a direction parallel to the axis AX. The first and second lead-out wirings 21 and 22 refer to the portions that deviate from the overlapping portions. The winding portion 23 is formed into a substantially rectangular shape when viewed from the direction of the axis AX, but is not limited to this shape. The shape of the winding portion 23 may also be, for example, circular, elliptical, or other polygonal shapes.

[0053] like Figure 2 as well as Figure 3 As shown, the winding section 23 includes: a plurality of coil wiring layers 201, 202, 203, 204 each wound along a plane; and via wirings 601, 602, 603 connecting the plurality of coil wiring layers 201, 202, 203, 204. The number of coil wiring layers and the number of via wirings are not limited to the above numbers.

[0054] The first to fourth coil wiring layers 201, 202, 203, and 204 are respectively sandwiched by the insulating layers 11 and are sequentially stacked along the direction of the axis AX (direction Y). That is, the stacking direction of the insulating layers 11 is the same direction as the direction of the axis AX.

[0055] The first to fourth coil wiring layers 201, 202, 203, 204 are wound on the main surface (XZ plane) of the insulating layer 11 orthogonal to the direction of the axis AX. The number of windings of the coil wiring layers 201, 202, 203, 204 is less than one turn, but may be one turn or more.

[0056] The pad portion 24 connected to the via wiring is provided at one end of the first and fourth coil wiring layers 201, 204 and at both ends of the second and third coil wiring layers 202, 203. When viewed from the direction of the axis AX, the pad portion 24 protrudes further to the inside of the coil 20 than the first to fourth coil wiring layers 201, 202, 203, 204. Figure 3 As shown, when viewed from the direction of the axis AX, a portion of the pad portion 24 does not protrude further to the outside of the coil 20 than the first to fourth coil wiring layers 201, 202, 203, 204, and the pad portion 24 and the first to fourth coil wiring layers 201, 202, 203, 204 are substantially on the same surface with respect to the front end of the outer side of the coil 20. In addition, the pad portion 24 may protrude to the outside, or may protrude to both the inside and the outside.

[0057] The pad portion 24 is circular. The diameter of the pad portion 24 is larger than the wiring width of the first to fourth coil wiring layers 201, 202, 203, 204. The wiring width of the first to fourth coil wiring layers 201, 202, 203, 204 is the dimension in the width direction orthogonal to the extension direction of the first to fourth coil wiring layers 201, 202, 203, 204 when viewed from the direction of the axis AX. The above wiring width is the average value of the wiring width of the coil 20.

[0058] The first to third via wirings 601, 602, 603 penetrate the insulating layer 11 in the thickness direction (Y direction). Moreover, the coil wiring layers adjacent to each other in the stacking direction are electrically connected in series via the via wirings. Specifically, the first coil wiring layer 201 is electrically connected to the second coil wiring layer 202 via the first via wiring 601. The second coil wiring layer 202 is electrically connected to the third coil wiring layer 203 via the second via wiring 602. The third coil wiring layer 203 is electrically connected to the fourth coil wiring layer 204 via the third via wiring 603.

[0059] In this way, the plurality of coil wiring layers 201, 202, 203, and 204 form a spiral while being electrically connected in series. However, all coil wiring layers do not need to be electrically connected in series, and some or all of the coil wiring layers may be electrically connected in parallel.

[0060] The first lead wiring 21 is connected to the first coil wiring layer 201 at one end and to the first external electrode 30 at the other end. The second lead wiring 22 is connected to the fourth coil wiring layer 204 at one end and to the second external electrode 40 at the other end.

[0061] The first lead wiring 21 includes: a first connection portion 211 connected to the winding portion 23; and a first curved portion 212 including a curved surface curved from the first connection portion 211 toward the first embedded portion 31 side. The curved surface of the first curved portion 212 has a concave shape, and the length dimension L1 of the first curved portion 212 on the first contact surface between the first embedded portion 31 and the first lead wiring 21 is larger than the wiring width W1 of the first connection portion 211. In a cross section that is orthogonal to the first end surface 15 and the top surface 18 and crosses the first curved portion 212, the length dimension L1 is larger than the height dimension D1 of the first embedded portion 31 in a direction perpendicular to the first contact surface. In addition, the concave shape is a shape that is concave toward the first curved portion 212 side, for example, a shape having rounded corners or a part of an ellipse. In other words, the first curved portion 212 is concave from the first curved portion 212 toward the base body 10 side. In addition, the wiring width W1 of the first connection portion 211 is the same as the wiring width of the winding portion 23. In addition, in the present embodiment, the length dimension refers to the maximum value of the dimension in the lateral direction (Z direction) of the first bonding surface between the first embedded portion 31 and the first curved portion 212. The wiring width W1 of the connection portion refers to the width between the wirings in the first connection portion 211. In addition, in the present specification, the portion of the first lead wiring 21 that contacts the first embedded portion 31 and has a concave curved surface is set as the first curved portion 212, and the portion that connects the first curved portion to the winding portion 23 and has a certain wiring width W1 is set as the first connection portion 211. In addition, the length of the first connection portion 211 along the extension direction is not particularly specified, and may be shorter than the wiring width W1 or longer than the wiring width W1.

[0062] In existing inductor components, attempts are made to reduce the wiring width of the lead-out wiring and reduce the height dimension of the external electrode. However, in the above structure, there is a situation where the current density per unit area of ​​the plating becomes higher. In such a case, if the plating has, for example, a Ni plating and a Sn plating, electromigration occurs in the plating, and Ni diffuses into the Sn plating. As a result, the Ni plating disappears, the Sn plating contacts the buried portion, and the atoms (for example, Ag) contained in the buried portion diffuse into the Sn plating (Ag corrosion caused by Sn). In such a case, the current is less likely to flow, and the DC resistance (Rdc) increases, resulting in heat generation and a greater risk of disconnection.

[0063] In contrast, in the present disclosure, the length dimension L1 of the first contact surface between the first curved portion 212 and the first embedded portion 31 is larger than the wiring width W1 of the first connecting portion 211, and the length dimension L1 is larger than the height dimension D1 of the first embedded portion 31. Therefore, even if the height dimension D1 of the first embedded portion 31 is small, the amount of current flowing through each unit area can be reduced by increasing the area of ​​the first contact surface between the first curved portion 212 and the first embedded portion 31, and heat can be diffused in the first lead-out wiring 21. As a result, the temperature rise in the first contact surface can be suppressed, and electromigration can be suppressed. For example, in the case where the first plating layer 33 includes a Ni plating layer and a Sn plating layer, even if the height dimension D1 of the first embedded portion 31 is reduced, the disappearance of the Ni plating layer can be suppressed. As a result, the Sn plating layer can be prevented from contacting the first embedded portion 31, and the diffusion of atoms contained in the first embedded portion 31 can be reduced.

[0064] In addition, by reducing the wiring width W1, when viewed from the extension direction of the axis AX, the overlapping portion of the first lead wiring 21 and the winding portion 23 can be reduced, and the magnetic flux is not blocked, so the inductance can be obtained efficiently. In addition, by reducing the wiring width W1 and increasing the length dimension L1, the residual stress generated in the first lead wiring 21 can be suppressed to an extremely low level, thereby suppressing cracks. In addition, in the present embodiment, the height dimension refers to the dimension in the direction (height direction) perpendicular to the first bonding surface when viewed from the first bonding surface between the first embedded portion 31 and the first curved portion 212. In addition, when the first bonding surface is unclear, the portion where multiple external electrode conductor layers 35 overlap each other when viewed from a direction parallel to the axis AX can also be set as the first embedded portion 31, and the boundary between the first embedded portion 31 and the first curved portion 212 can be set as the first bonding surface.

[0065] Preferably, the surface of the first curved portion 212 is smoothly curved. That is, the first curved portion 212 has no corners. If there are corners in the first curved portion 212, the current is concentrated at the corners, and the high-frequency Q value cannot be obtained. In contrast, by having a curved shape, there is no corner where the current is concentrated, and a high-frequency Q value can be obtained.

[0066] Preferably, in the first lead wiring 21, when projected onto the second side surface 14 along the direction of the axis AX, the maximum height dimension D2 of the first bent portion 212 in a direction parallel to the height dimension D1 of the embedded portion is larger than the height dimension D1 of the first embedded portion 31. With the above structure, the surface area of ​​the first lead wiring 21 is increased, and heat can be further diffused in the first lead wiring 21.

[0067] Preferably, in a cross section orthogonal to the first end surface 15 and the top surface 18, the rate of increase of the wiring width of the first curved portion 212 increases from the contact surface between the first connecting portion 211 and the first curved portion 212 toward the contact surface between the first embedded portion 31 and the first curved portion 212. That is, the wiring width of the first curved portion 212 is larger than the wiring width W1 of the first connecting portion 211, and has the largest length dimension L1 in the first contact surface between the first curved portion 212 and the first embedded portion 31. By having the above structure, the area of ​​the first contact surface between the first curved portion 212 and the first embedded portion 31 becomes larger, and the amount of current flowing per unit area can be reduced. In addition, the rate of increase means that the increase in the wiring width per unit length along the extension direction of the first curved portion 212 increases as it approaches the first embedded portion 31. In addition, when measuring the wiring width of the first curved portion 212, when a part of the wiring width overlaps with the first embedded portion 31, it is assumed that the part is not included in the wiring width.

[0068] Preferably, when projected onto the second side surface 14 along the direction of the axis AX, the first contact surface between the first embedded portion 31 and the first curved portion 212 has, in order, a first contact point a1 having a maximum height dimension D2 of the first curved portion 212, a second contact point a2 having a height dimension D3 which is half of the height dimension D2 which is the maximum value of the height dimension of the first curved portion 212, and a third contact point a3 where the surface of the first curved portion 212 contacts the first embedded portion 31. That is, the first contact point a1, the second contact point a2, and the third contact point a3 are arranged in the reverse Z direction. At this time, the length dimension L3 along the contact surface between the first embedded portion 31 and the first curved portion 212 from the second contact point a2 to the third contact point a3 is larger than the length dimension L2 along the contact surface between the first embedded portion 31 and the first curved portion 212 from the first contact point a1 to the second contact point a2. With the above structure, the area of ​​the first contact surface becomes larger, the amount of current flowing per unit area can be reduced, and the temperature rise in the first contact surface can be suppressed. In addition, the first contact point a1, the second contact point a2, and the third contact point a3 may also be arranged along the Z direction.

[0069] Preferably, the length dimension L1 of the first contact surface between the first curved portion 212 and the first embedded portion 31 is greater than 10 μm. By having the above structure, the area of ​​the first contact surface becomes larger, and the amount of current flowing through each unit area can be reduced. In addition, the surface area of ​​the first curved portion 212 becomes larger, and the heat generated in the first curved portion 212 can be diffused. The upper limit value of the length dimension L1 is not particularly limited, for example, it can also be 80 μm when the length dimension L of the first embedded portion 31 is 121 μm. In addition, the upper limit value of the length dimension L1 is not particularly limited, for example, it can also be less than 2 / 3 of the length dimension L of the first embedded portion 31.

[0070] Preferably, when projected onto the second side surface 14 along the direction of the axis AX, the ratio of the length dimension L1 of the first contact surface to the length dimension L of the first embedded portion 31 is greater than 1 / 8 and less than 2 / 3. In addition, the length dimension L refers to the length of the portion of the first embedded portion 31 exposed on the surface of the blank 10 when viewed from the direction of the axis AX, and the length dimension L1 refers to the length of the contact surface between the first embedded portion 31 and the first curved portion 212 when viewed from the direction of the axis AX. By making the above ratio greater than 1 / 8, the area of ​​the first contact surface becomes larger, and the amount of current flowing through each unit area can be reduced. By making the above ratio less than 2 / 3, the distance between the winding portion 23 and the first curved portion 212 can be appropriately maintained, and parasitic capacitance can be suppressed. In addition, the first curved portion 212 can be isolated from the winding portion 23, and the risk of short circuit between the first curved portion 212 and the winding portion 23 can be reduced. In addition, the residual stress can be appropriately suppressed, and the generation of cracks generated between the first embedded portion 31 and the first curved portion 212 can be suppressed. If the above ratio is too small, the risk of disconnection caused by migration increases. If the above ratio is too large, the distance between the winding portion 23 and the first lead wiring 21 is close, and the parasitic capacitance increases. In addition, the first curved portion 212 is close to the winding portion 23, and the risk of short circuit increases. In addition, the residual stress increases, so the risk of cracks increases. In addition, exposure refers to appearing on the surface of the blank 10, and it can also be completely exposed to the outside without overlapping with other layers or parts, or it can overlap other layers or parts on the exposed part.

[0071] Preferably, at least one of the first external electrode 30 and the second external electrode 40 further includes a first plating layer 33 covering at least a portion of the portion of the first embedded portion 31 exposed on the surface of the base body 10, and the first plating layer 33 includes metal atoms different from those of the first embedded portion 31 and the first lead wiring 21. Specifically, the first plating layer 33 includes Ni, and the first embedded portion 31 and the first lead wiring 21 do not include Ni. In the case of the above structure, electromigration is not easily caused in the first external electrode 30.

[0072] Preferably, when the blank 10 and the coil 20 are projected onto the second side surface 14 along the direction of the axis AX of the coil 20, the outer peripheral surface 20a on the inner diameter side of the first curved portion 212 has a curved surface. By having the above-mentioned manner, the first curved portion 212 has a smoother surface. When the first curved portion 212 has a corner, the current is easily concentrated at the corner, but by having a smooth surface, the current is not easily concentrated.

[0073] In one embodiment, when the blank 10 and the coil 20 are projected onto the second side surface 14 along the direction of the axis AX of the coil 20, the outer peripheral surface 20a of the inner diameter side of the first curved portion 212 extends from the first connecting portion 211 side of the first curved portion 212 to the first embedded portion 31, depicting a rounded shape, and the rounded corner radius of the rounded corner shape is 10 μm or more. The rounded corner radius is preferably 30 μm or more, and more preferably 100 μm or more. The rounded corner radius is, for example, 300 μm or less. If the rounded corner radius is too large, the distance between the first curved portion 212 and the winding portion 23 becomes smaller, and the first curved portion 212 and the winding portion 23 may contact and short-circuit.

[0074] Preferably, when the base body 10 and the coil 20 are projected onto the second side surface 14 along the direction of the axis AX of the coil 20, the outer peripheral surface 20a on the inner diameter side of the coil 20 in the first bent portion 212 describes a rounded shape. In the present embodiment, in the inductor component 1 having an L-shaped electrode, by providing the rounded shape of the first bent portion 212 on the outer peripheral surface 2a side on the inner diameter side, the adhesion between the first bent portion 212 and the first embedded portion 31 can be improved.

[0075] Preferably, the height dimension D1 of the first embedded portion 31 is less than 20 μm. The lower limit of the height dimension D1 of the first embedded portion 31 is not particularly limited, and is, for example, 10 μm. The value of the height dimension D1 of the first embedded portion 31 is preferably smaller in the enlarged view of the coil configuration area. If the value of the height dimension D1 of the first embedded portion 31 is too small, current concentration becomes severe.

[0076] Preferably, the height dimension D4 of the first plating layer 33 in a direction parallel to the first height dimension D1 is 10 μm or less. By having the above structure, the DC resistance can be reduced and the Q value can be improved. The height dimension D4 of the first plating layer 33 is preferably 8 μm or less. The lower limit of the height dimension D4 is not particularly limited, for example, 1.5 μm. In addition, the height dimension D1 and the height dimension D4 are similar to each other. Figure 2 As shown, they are all sizes in the X-axis direction, and the total of the height dimension D1 and the height dimension D4 is the height dimension of the first embedded portion 31 and the first plating layer 33 .

[0077] Furthermore, in the above description, the first lead wiring 21 and the first external electrode 30 are described, but the second lead wiring 22 and the second external electrode 40 can also have the same structure.

[0078] (Method of Manufacturing Inductor Component 1)

[0079] Next, an example of a method for manufacturing the inductor component 1 will be described. The method for manufacturing the inductor component 1 is not limited to the following method, and other manufacturing methods may be used.

[0080] First, an insulating paste containing borosilicate glass as a main component and a conductive paste containing Ag as a main component are prepared. The insulating paste becomes an insulating layer after firing described later. The conductive paste becomes a coil wiring layer, lead wiring, via wiring, and embedded portion according to the coating position after firing described later.

[0081] Next, an insulating paste is applied by screen printing to form a portion to be an insulating layer.

[0082] A necessary amount of conductive paste is applied on the applied insulating paste by screen printing, and portions to be the coil wiring layer, lead wiring, and embedded portions are formed by a patterning process using photolithography.

[0083] Next, a necessary amount of insulating paste is applied by screen printing on the insulating paste after the conductive paste is applied and patterned, and openings are provided in the insulating paste by a patterning process using photolithography.

[0084] Next, a necessary amount of conductive paste is applied by screen printing on the insulating paste with the opening. At this time, the conductive paste is filled in the opening to form the portion that will become the via wiring and the embedded portion. In addition, similarly to the above, the portion that will become the coil wiring layer, the lead wiring, and the embedded portion is formed by a patterning process based on photolithography.

[0085] Next, the unfired laminate is fired under predetermined conditions to obtain a coil wiring layer, lead wiring, via wiring, and embedded portion from the conductive paste, and an insulating layer from the insulating paste.

[0086] The green body is then subjected to barrel processing, and then, the portion where the embedded portion is exposed from the green body is plated with Ni plating having a thickness of 2 μm to 10 μm and Sn plating having a thickness of 2 μm to 10 μm to form a plating layer. Through the above steps, the inductor component 1 is completed.

[0087] In addition, in the above, the unfired laminate is fired, but instead, the mother laminate may be fired after the through hole is provided, and then the through hole is filled with magnetic paste to form the internal magnetic component. In this case, after the magnetic paste is filled, the laminate is cut into layers by cutting or the like. In this case, the internal magnetic component and the external magnetic component can be formed by thermally curing the magnetic paste.

[0088] <Second embodiment>

[0089] Figure 4 This is a perspective front view of the inductor component 1A according to the second embodiment as seen from the first side surface. Figure 51A is an exploded view of the inductor component 1A of the second embodiment. The inductor component 1A is different from the inductor component 1 of the first embodiment in the shape of the coil 20. This difference is described below. The other structures are the same as those of the first embodiment, and the same reference numerals as those of the first embodiment are marked and their description is omitted.

[0090] The coil 20A includes: a winding portion 23A; a first lead wiring 21A located between a first end of the winding portion 23A and the first external electrode 30; and a second lead wiring 22A located between a second end of the winding portion 23A and the second external electrode 40. Figure 4 as well as Figure 5 The coil 20A is made of the same material as the coil 20 .

[0091] The winding portion 23A is formed into an ellipse when viewed from the direction of the axis AX. The winding portion 23A is elliptical, so that it is not easy to generate firing residual stress and current concentration. In addition, the winding portion 23A may have a shape other than an ellipse.

[0092] The winding portion 23A includes: a plurality of coil wiring layers 201A, 202A each wound along a plane; and a longitudinal via wiring 601A connecting the plurality of coil wiring layers 201A, 202A. By connecting the coil wiring layers via the longitudinal via wiring, the coil 20A can be formed more stably. In addition, the number of coil wiring layers and the number of via wirings are not limited to the above. In addition, the via wiring may also have a shape other than the longitudinal via wiring, and may also be circular or quadrilateral. The end of the coil wiring layer connected to the circular via wiring constitutes a circular pad portion, and the diameter of the circular pad portion is larger than the line width of the middle portion of the coil wiring layer. In addition, via wirings of different shapes may also be provided.

[0093] <Third embodiment>

[0094] Figure 6 This is a perspective front view of the inductor component 1B according to the third embodiment, as seen from the first side surface. Figure 7 This is an exploded view of the inductor component 1B of the third embodiment. The inductor component 1B is different from the inductor component 1 of the first embodiment in terms of the external electrodes 30B, 40B and the coil 20B. The difference is described below. The other structures are the same as those of the first embodiment, and the same reference numerals as those of the first embodiment are marked and their descriptions are omitted.

[0095] like Figure 6 to Figure 7As shown, the inductor component 1B has: a body 10; a coil 20B provided on the body 10; and a first external electrode 30B and a second external electrode 40B provided on the body 10 and electrically connected to the coil 20B. The coil 20B has: a winding portion 23B; a first lead wiring 21B connected between a first end of the winding portion 23B and the first external electrode 30B; and a second lead wiring 22B connected between a second end of the winding portion 23B and the second external electrode 40B. The coil 20B is formed by the same structure as the coil 20. In addition, Figure 6 as well as Figure 7 The plating layer is not described.

[0096] The first external electrode 30B is a bottom electrode provided on the bottom surface 17, and has a first embedded portion 31B and a plating layer formed on the surface of the first embedded portion 31B. The second external electrode 40B is a bottom electrode provided on the bottom surface 17, and has a first embedded portion 41B and a plating layer formed on the surface of the first embedded portion 41B. By having the above structure, the parasitic capacitance between the external electrode and the coil is reduced, thereby improving the high-frequency characteristics. In addition, the first external electrode 30B has a structure in which a plurality of first external electrode conductor layers 35B embedded in the body 10 are stacked in surface contact, and the second external electrode 40B has a structure in which a plurality of second external electrode conductor layers 45B embedded in the body 10 are stacked in surface contact. The first external electrode 30B and the second external electrode 40B are formed of the same material as the first embodiment.

[0097] The coil 20B includes a winding portion 23B, a first lead wiring 21B connected between a first end of the winding portion 23B and a first external electrode 30B, and a second lead wiring 22B connected between a second end of the winding portion 23B and a second external electrode 40B. The coil 20B is formed of the same material as the coil 20 .

[0098] The winding section 23B includes: a plurality of coil wiring layers 201B, 202B, 203B, 204B each wound along a plane; and via wirings 601B, 602B, 603B connecting the plurality of coil wiring layers 201B, 202B, 203B, 204B. The number of coil wiring layers and the number of via wirings are not limited to the above.

[0099] The first to fourth coil wiring layers 201B, 202B, 203B, and 204B are made of the same material as the coil wiring layers of the first embodiment, and are provided in the same manner as the first embodiment.

[0100] The first to third via wirings 601B, 602B, and 603B are arranged at a position closer to the bottom surface 17 than the axis AX. Unlike the first embodiment, in the third embodiment, the first to third via wirings 601B, 602B, and 603B are not arranged at the corners of the coil wiring layer. In the case of the first embedded portion 31B and the first embedded portion 41B, by not arranging the via wirings 601B, 602B, and 603B at the corners of the coil wiring layer, the distance from the end face of the blank 10 becomes larger, thereby reducing the risk of disconnection of the via wiring at cracks caused by external forces.

[0101] When viewed from the direction of the axis AX, the land portion 24 protrudes further toward the inner side of the coil 20B than the first to fourth coil wiring layers 201B, 202B, 203B, and 204B. Figure 6 As shown, when the pad portion 24 is viewed from the direction of the axis AX, it does not protrude further to the outside of the coil 20B than the first to fourth coil wiring layers 201B, 202B, 203B, 204B, and the pad portion 24 and the first to fourth coil wiring layers 201B, 202B, 203B, 204B are substantially on the same surface as each other at the front end of the outer side of the coil 20B. By having the above structure, it is possible to suppress the increase of the parasitic capacitance between the via wiring 601B, 602B, 603B and the first external electrode 30B and the second external electrode 40B.

[0102] The first lead wiring 21B is connected to the first coil wiring layer 201B at one end and to the first external electrode 30B at the other end. The first lead wiring 21B has: a first connection portion 211B connected to the winding portion 23B, and a first curved portion 212B including a curved surface that curves from the first connection portion 211B toward the first embedded portion 31B side. The curved surface of the first curved portion 212B has a concave shape, and the length dimension L1 of the first curved portion 212B on the first contact surface between the first embedded portion 31B and the first lead wiring 21 is larger than the wiring width W1 of the first connection portion 211. When projected onto the second side surface 14 along the axis AX, the length dimension L1 is larger than the height dimension D1 of the first embedded portion 31 in the direction perpendicular to the first contact surface. In addition, in the present embodiment, the length dimension refers to the maximum value of the dimension in the lateral direction (X direction) of the first bonding surface between the first embedded portion 31B and the first curved portion 212B.

[0103] The second lead wiring 22B is connected to the fourth coil wiring layer 204B at one end and to the second external electrode 40B at the other end. The second lead wiring 22B has: a connection portion connected to the winding portion 23B, and a curved portion including a curved surface that curves from the connection portion toward the first embedded portion. The curved surface of the curved portion has a concave shape, and a length dimension L1 of the curved portion on the contact surface between the first embedded portion 41B and the lead wiring is larger than the wiring width W1 of the connection portion.

[0104] Preferably, the surface of the first curved portion 212B is smoothly curved. That is, the first curved portion 212B has no corners. By having a curved shape, there is no corner where the generated current is concentrated, and a high frequency Q value can be obtained.

[0105] Preferably, when projected along the axis AX onto the second side surface 14, the maximum height D2 of the first bent portion 212B is greater than the height D1 of the first embedded portion 31B. With the above structure, the surface area of ​​the first lead wiring 21B is increased, and heat can be further diffused in the first lead wiring 21B.

[0106] Preferably, in a cross section orthogonal to the first end surface 15 and the top surface 18, the rate of increase of the wiring width of the first curved portion 212B increases from the contact surface between the first connecting portion 211B and the first curved portion 212B toward the contact surface between the first embedded portion 31B and the first curved portion 212B. That is, the wiring width of the first curved portion 212B is larger than the wiring width W1 of the first connecting portion 211B, and has the largest length dimension L1 in the first contact surface between the first curved portion 212B and the first embedded portion 31B. With the above structure, the area of ​​the first contact surface between the first curved portion 212B and the first embedded portion 31B increases, and the amount of current flowing per unit area can be reduced. In addition, the rate of increase means that the increase in the wiring width per unit length along the extension direction of the first curved portion 212B increases as it approaches the first embedded portion 31B.

[0107] Preferably, the length dimension L1 of the first contact surface between the first curved portion 212B and the first embedded portion 31B is greater than 10 μm. By having the above structure, the area of ​​the first contact surface becomes larger, and the amount of current flowing through each unit area can be reduced. In addition, the surface area of ​​the first curved portion 212B becomes larger, and the heat generated in the first curved portion 212B can be diffused. The upper limit value of the length dimension L1 is not particularly limited, for example, when the length dimension L of the first embedded portion 31 is 121 μm, it is 80 μm. In addition, the upper limit value of the length dimension L1 is not particularly limited, for example, it is less than 2 / 3 relative to the length dimension L of the first embedded portion 31 (i.e., L1 / L).

[0108] Preferably, when projected onto the second side surface 14 along the direction of the axis AX, the ratio of the length dimension L1 of the first contact surface to the length dimension L of the first embedded portion 31B is greater than 1 / 8 and less than 2 / 3. By making the above ratio greater than 1 / 8, the area of ​​the first contact surface becomes larger, and the amount of current flowing through each unit area can be reduced. By making the above ratio less than 2 / 3, the distance between the winding portion 23B and the first curved portion 212B can be appropriately maintained, and the parasitic capacitance can be suppressed. In addition, the first curved portion 212B can be isolated from the winding portion 23B, and the risk of short circuit between the first curved portion 212B and the winding portion 23B can be reduced. Moreover, the residual stress can be appropriately suppressed, and the generation of cracks generated between the first embedded portion 31B and the first curved portion 212B can be suppressed. If the above ratio is too small, the risk of disconnection caused by migration becomes larger. If the above ratio is too large, the distance between the winding portion 23B and the first lead-out wiring 21B is close, and the parasitic capacitance increases. In addition, the first curved portion 212B is close to the winding portion 23B, and the risk of short circuit increases. Also, the risk of cracks increases because the residual stress increases.

[0109] Preferably, at least one of the first external electrode 30B and the second external electrode 40B further includes a first plating layer (not shown) covering at least a portion of the portion of the first embedded portion 31B exposed on the surface of the base body 10, and the first plating layer includes metal atoms different from those of the first embedded portion 31B and the first lead wiring 21B. Specifically, the first plating layer includes Ni, and the first embedded portion 31B and the first lead wiring 21B do not include Ni. In the case of the above structure, electromigration is not easily caused in the first external electrode 30B.

[0110] Preferably, when the blank 10 and the coil 20B are projected onto the second side surface 14 along the direction of the axis AX of the coil 20B, the outer peripheral surface 20aB on the inner diameter side of the first curved portion 212B has a curved surface. By having the above-mentioned manner, the first curved portion 212B has a smoother surface. When the first curved portion 212B has a corner, the current is easily concentrated at the corner, but by having a smooth surface, the current is not easily concentrated.

[0111] In one embodiment, when the blank 10 and the coil 20B are projected onto the second side surface 14 along the direction of the axis AX of the coil 20B, the outer peripheral surface 20aB on the inner diameter side of the first curved portion 212B extends from the first connecting portion 211B side of the first curved portion 212B to the first embedded portion 31B, depicting a rounded shape, and the rounded corner radius of the rounded corner shape is 10 μm or more. The rounded corner radius is preferably 30 μm or more, and more preferably 100 μm or more. The rounded corner radius is, for example, 300 μm or less. If the rounded corner radius is too large, the distance between the first curved portion 212B and the winding portion 23B becomes smaller, and the first curved portion 212B and the winding portion 23B may contact and short-circuit.

[0112] Preferably, the height dimension of the first plating layer in a direction parallel to the height dimension D1 is 10 μm or less. By having the above structure, the DC resistance can be reduced and the Q value can be improved. The height dimension of the first plating layer is preferably 8 μm or less. The lower limit of the height dimension of the first plating layer is not particularly limited, for example, 1.5 μm.

[0113] Preferably, the coil 20B has an outer peripheral surface 20aB on the inner diameter side and an outer peripheral surface 20bB on the outer diameter side opposite to the inner diameter. When the blank 10 and the coil 20B are projected onto the second side surface 14 along the direction of the axis AX of the coil 20B, the outer peripheral surface 20aB on the inner diameter side of the first curved portion 212B and the outer peripheral surface 20bB on the outer diameter side both have curved surfaces. By having the above-mentioned manner, the first curved portion 212B has a smoother surface. In the case where the first curved portion 212B has a corner, the current is easily concentrated at the corner, but by having a smooth surface, it is not easy to generate current concentration. In addition, it can also be that only the outer peripheral surface 20aB on the inner diameter side has a curved surface, and it can also be that only the outer peripheral surface 20bB on the outer diameter side has a curved surface. In addition, the outer peripheral surface 20aB on the inner diameter side and the outer peripheral surface 20bB on the outer diameter side can also have curved surfaces of different shapes.

[0114] Preferably, the coil 20B has an outer peripheral surface 20aB on the inner diameter side and an outer peripheral surface 20bB on the outer diameter side opposite to the inner diameter, and when the base body 10 and the coil 20B are projected along the direction of the axis AX of the coil 20B onto the second side surface 14, both the outer peripheral surface 20aB on the inner diameter side and the outer peripheral surface 20bB on the outer diameter side of the first bent portion 212B are rounded. In this embodiment, in the inductor component 1B having a bottom electrode, by providing the rounded shape on the outer peripheral surface 20aA side on the inner diameter side and the outer peripheral surface 20aB side on the outer diameter side, the adhesion between the first bent portion 212B and the first embedded portion 31B can be improved.

[0115] Furthermore, in the above description, the first lead wiring 21B and the first external electrode 30B are described, but the second lead wiring 22B and the second external electrode 40B can also have the same structure.

[0116] <Fourth embodiment>

[0117] Figure 8 This is a perspective front view of the inductor component 1C according to the fourth embodiment as seen from the top surface side. 9A to 9C It is an exploded view of the inductor component 1C according to the fourth embodiment. Fig.9A The lower right dotted line and Fig. 9B The upper left dotted line connects Fig. 9B The lower right dotted line and Fig. 9C . In the first embodiment, the axis of the coil is set in a direction perpendicular to the first side surface 13 and the second side surface 14, but in the present embodiment, the axis of the coil is set in a direction perpendicular to the top surface and the bottom surface. In addition, the first external electrode 30 and the second external electrode 40 are L-shaped electrodes in the first embodiment, but in the fourth embodiment, they are end surface electrodes arranged on the first end surface 15 and the second end surface 16. The following describes the difference. The other structures are the same as those in the first embodiment, and are marked with the same figure marks as those in the first embodiment and their descriptions are omitted.

[0118] like Figures 8 to 9C As shown, the inductor component 1C includes: a green body 10; a coil 20C provided on the green body 10; and a first external electrode 30C and a second external electrode 40C provided on the green body 10 and electrically connected to the coil 20C.

[0119] The first external electrode 30C is an end surface electrode provided on the first end surface 15. The first external electrode 30C includes: a first embedded portion 31C provided in the body and extending along the first end surface 15; and a first plating layer located on the surface of the body 10 and formed on the surface of the first embedded portion 31C. The second external electrode 40C is an end surface electrode provided on the second end surface 16. The second external electrode 40C includes: a first embedded portion 41C provided in the body and extending along the second end surface 16; and a first plating layer located on the surface of the body 10 and formed on the surface of the first embedded portion 41C. By having the above-mentioned structure, the influence of magnetic coupling with adjacent components is reduced, and the design freedom of component configuration is improved. The first and second external electrodes 30C, 40C are formed of the same material as the external electrodes of the first embodiment. In addition, the first and second external electrodes 30C, 40C may also have other forms. In addition, in Figure 8 , Fig.9A , Fig. 9B as well as Fig. 9C The plating is not described.

[0120] like Fig.9A , Fig. 9B as well as Fig. 9C As shown, the first embedded portion 31C has a structure in which a plurality of first external electrode conductor layers 35C embedded in the body 10 are stacked in surface contact. The first embedded portion 41C has a structure in which a plurality of second external electrode conductor layers 45C embedded in the body 10 are stacked in surface contact. The first external electrode conductor layers 35C extend along the first end surface 15, and the second external electrode conductor layers 45C extend along the second end surface 16.

[0121] The coil 20C has a winding portion 23C, a first lead wiring 21C connected between a first end of the winding portion 23C and a first external electrode 30C, and a second lead wiring 22C connected between a second end of the winding portion 23C and a second external electrode 40C. The coil 20C has the same structure as the coil 20 .

[0122] like Figure 8 , Fig.9A , Fig. 9B as well as Fig. 9C As shown, the winding portion 23C is wound in a spiral shape along the axis AX1 direction which is parallel to the first end surface 15 and intersects the top surface 18 and the bottom surface 17. That is, the axis AX1 is orthogonal to the top surface 18 and the bottom surface 17.

[0123] The winding portion 23C includes: a plurality of coil wiring layers 201D, 202D, 203D, 204D, 205D, 206D, 207D, 208D, 209D, 210D, 211D, 212D each wound along a plane; and via wirings 601C, 602C, 603C, 604C, 605C, 606C, 607C, 608C, 609C, 610C, 611C connecting the plurality of coil wiring layers. The number of coil wiring layers and the number of via wirings are not limited to the above.

[0124] The first to twelfth coil wiring layers 201D, 202D, 203D, 204D, 205D, 206D, 207D, 208D, 209D, 210D, 211D, and 212D are sandwiched by insulating layers 11 and stacked in sequence along the axis AX1 (Z direction). The first to twelfth coil wiring layers 201D, 202D, 203D, 204D, 205D, 206D, 207D, 208D, 209D, 210D, 211D, and 212D are made of the same material as the coil wiring layers of the first embodiment.

[0125] The first to eleventh via wirings 601C, 602C, 603C, 604C, 605C, 606C, 607C, 608C, 609C, 610C, 611C penetrate the insulating layer 11 in the height direction (Z direction). The coil wiring layers adjacent in the stacking direction are electrically connected in series via the via wirings. Specifically, the first coil wiring layer 201D is electrically connected to the second coil wiring layer 202D via the first via wiring 601C. The second coil wiring layer 202D is electrically connected to the third coil wiring layer 203D via the second via wiring 602C. The third coil wiring layer 203D is electrically connected to the fourth coil wiring layer 204D via the third via wiring 603C. The fourth coil wiring layer 204D is electrically connected to the fifth coil wiring layer 205D via the fourth via wiring 604C. The fifth coil wiring layer 205D is electrically connected to the sixth coil wiring layer 206D via the fifth conductive hole wiring 605C. The sixth coil wiring layer 206D is electrically connected to the seventh coil wiring layer 207D via the sixth conductive hole wiring 606C. The seventh coil wiring layer 207D is electrically connected to the eighth coil wiring layer 208D via the seventh conductive hole wiring 607C. The eighth coil wiring layer 208D is electrically connected to the ninth coil wiring layer 209D via the eighth conductive hole wiring 608C. The ninth coil wiring layer 209D is electrically connected to the tenth coil wiring layer 210D via the ninth conductive hole wiring 609C. The tenth coil wiring layer 210D is electrically connected to the eleventh coil wiring layer 211D via the tenth conductive hole wiring 610C. The eleventh coil wiring layer 211D is electrically connected to the twelfth coil wiring layer 212D via the eleventh conductive hole wiring 611C.

[0126] The first to eleventh via wirings 601C, 602C, 603C, 604C, 605C, 606C, 607C, 608C, 609C, 610C, and 611C are made of the same material as the coil wiring layer of the first embodiment.

[0127] The first lead wiring 21C is connected to the first coil wiring layer 201D at one end and to the first external electrode 30C at the other end. The first lead wiring 21C has: a first connection portion 211C connected to the winding portion 23C; and a first curved portion 212C including a curved surface that curves from the first connection portion 211C toward the first embedded portion 31C side. The curved surface of the first curved portion 212C has a concave shape, and the length dimension L1 of the first curved portion 212C on the first contact surface between the first embedded portion 31C and the first lead wiring 21C is larger than the wiring width W1 of the first connection portion 211C. When projected onto the bottom surface 17 along the axis AX1, the length dimension L1 is larger than the height dimension D1 of the first embedded portion 31C in the direction perpendicular to the first contact surface. In addition, in the present embodiment, the length dimension refers to the dimension from the second side surface 14 to the first side surface 13. That is, the length dimension refers to the size in the Y-axis direction. The height dimension refers to the dimension in the direction from the first end surface 15 to the second end surface 16. That is, the height dimension refers to the size in the X-axis direction.

[0128] The second lead wiring 22C is connected to the twelfth coil wiring layer 212D at one end and to the second external electrode 40C at the other end. The second lead wiring 22C has: a connection portion connected to the winding portion 23C; and a curved portion including a curved surface curved from the connection portion toward the first embedded portion. The curved surface of the curved portion has a concave shape, and a length dimension L1 of the curved portion on the contact surface between the first embedded portion 41C and the lead wiring is larger than the wiring width W1 of the connection portion.

[0129] Preferably, the surface of the first curved portion 212C is smoothly curved. That is, the first curved portion 212C has no corners. By having a curved shape, there is no corner where the generated current is concentrated, and a high frequency Q value can be obtained.

[0130] Preferably, when projected along the axis AX1 onto the bottom surface 17, the maximum height D2 of the first bent portion 212C is greater than the height D1 of the first embedded portion 31C. With the above structure, the surface area of ​​the first lead wiring 21C is increased, and heat can be further diffused in the first lead wiring 21C.

[0131] Preferably, when projected onto the bottom surface 17 along the axis AX1 direction, the rate of increase of the wiring width of the first curved portion 212C increases from the contact surface between the first connecting portion 211C and the first curved portion 212C toward the contact surface between the first embedded portion 31C and the first curved portion 212C. That is, the wiring width of the first curved portion 212C is larger than the wiring width W1 of the first connecting portion 211C, and has the largest length dimension L1 in the first contact surface between the first curved portion 212C and the first embedded portion 31C. By having the above structure, the area of ​​the first contact surface between the first curved portion 212C and the first embedded portion 31C increases, and the amount of current flowing per unit area can be reduced. In addition, the rate of increase means that the increase in the wiring width per unit length along the extension direction of the first curved portion 212C increases as it approaches the first embedded portion 31C.

[0132] Preferably, the length dimension L1 of the first contact surface between the first curved portion 212C and the first embedded portion 31C is greater than 10 μm. By having the above structure, the area of ​​the first contact surface becomes larger, and the amount of current flowing through each unit area can be reduced. In addition, the surface area of ​​the first curved portion 212C becomes larger, and the heat generated in the first curved portion 212C can be diffused. The upper limit value of the length dimension L1 is not particularly limited, and for example, it can also be 70 μm. In addition, the upper limit value of the length dimension L1 is not particularly limited, and for example, it can also be less than 1 / 2 of the length dimension L of the first embedded portion 31.

[0133] Preferably, when projected onto the bottom surface 17 along the direction of the axis AX, the ratio of the length dimension L1 of the first contact surface to the length dimension L of the first embedded portion 31C is greater than 1 / 8 and less than 2 / 3. By making the above ratio greater than 1 / 8, the area of ​​the first contact surface becomes larger, and the amount of current flowing through each unit area can be reduced. By making the above ratio less than 2 / 3, the distance between the winding portion 23C and the first curved portion 212C can be appropriately maintained, and the parasitic capacitance can be suppressed. In addition, the first curved portion 212C can be isolated from the winding portion 23C, and the risk of short circuit between the first curved portion 212C and the winding portion 23C can be reduced. In addition, the residual stress can be appropriately suppressed, and the generation of cracks generated between the first embedded portion 31C and the first curved portion 212C can be suppressed. If the above ratio is too small, the risk of disconnection caused by migration becomes greater. If the above ratio is too large, the distance between the winding portion 23C and the first lead wiring 21C is close, and the parasitic capacitance increases. In addition, the first bent portion 212C is close to the winding portion 23C, and the risk of short circuit increases. Also, the risk of cracks increases because the residual stress increases.

[0134] Preferably, at least one of the first external electrode 30C and the second external electrode 40C further includes a first plating layer (not shown) covering at least a portion of the portion of the first embedded portion 31C exposed on the surface of the base body 10, and the first plating layer includes metal atoms different from those of the first embedded portion 31C and the first lead wiring 21C. Specifically, the first plating layer includes Ni, and the first embedded portion 31C and the first lead wiring 21C do not include Ni. In the case of the above structure, electromigration is not easily caused in the first external electrode 30C.

[0135] Preferably, when the blank 10 and the coil 20C are projected along the axis AX1 direction onto the bottom surface 17, the outer peripheral surface 20aC on the inner diameter side of the first curved portion 212C has a curved surface. By having the above-mentioned manner, the first curved portion 212C has a smoother surface. When the first curved portion 212C has a corner, the current is easily concentrated at the corner, but by having a smooth surface, the current is not easily concentrated.

[0136] In one embodiment, when the blank 10 and the coil 20C are projected onto the bottom surface 17 along the axis AX1 direction, the outer peripheral surface 20aC on the inner diameter side of the first curved portion 212C extends from the first connecting portion 211C side of the first curved portion 212C to the first embedded portion 31C, and a fillet shape is depicted, and the fillet radius of the fillet shape is 10 μm or more. The fillet radius is preferably 30 μm or more, and more preferably 100 μm or more. The fillet radius is, for example, 300 μm or less. If the fillet radius is too large, the distance between the first curved portion 212C and the winding portion 23C becomes smaller, and the first curved portion 212C and the winding portion 23C may contact and short-circuit.

[0137] Preferably, the height dimension of the first plating layer in a direction parallel to the height dimension D1 is 10 μm or less. By having the above structure, the DC resistance can be reduced and the Q value can be improved. The height dimension of the first plating layer is preferably 8 μm or less. The lower limit of the height dimension of the first plating layer is not particularly limited, for example, 1.5 μm.

[0138] Preferably, the coil 20C has an outer peripheral surface 20aC on the inner diameter side and an outer peripheral surface 20bC on the outer diameter side opposite to the inner diameter. When the blank 10 and the coil 20C are projected onto the bottom surface 17 along the axis AX1 direction, the outer peripheral surface 20aC on the inner diameter side of the first curved portion 212C and the outer peripheral surface 20bC on the outer diameter side both have curved surfaces. By having the above-mentioned manner, the first curved portion 212C has a smoother surface. In the case where the first curved portion 212C has a corner, the current is easily concentrated at the corner, but by having a smooth surface, it is not easy to generate current concentration. In addition, it can also be that only the outer peripheral surface 20aC on the inner diameter side has a curved surface, and it can also be that only the outer peripheral surface 20bC on the outer diameter side has a curved surface. In addition, the outer peripheral surface 20aC on the inner diameter side and the outer peripheral surface 20bC on the outer diameter side can also have curved surfaces of different shapes.

[0139] Preferably, the coil 20C has an outer peripheral surface 20aC on the inner diameter side and an outer peripheral surface 20bC on the outer diameter side opposite to the inner diameter, and when the base body 10 and the coil 20C are projected along the axis AX1 direction onto the bottom surface 17, both the outer peripheral surface 20aC on the inner diameter side and the outer peripheral surface 20bC on the outer diameter side of the first bent portion 212C have rounded shapes. In the present embodiment, in the inductor component 1C having end surface electrodes, by providing rounded shapes on the outer peripheral surface 20aC on the inner diameter side and the outer peripheral surface 20bC on the outer diameter side, it is possible to improve the adhesion between the first bent portion 212C and the first embedded portion 31C.

[0140] Furthermore, in the above description, the first lead wiring 21C and the first external electrode 30C are described, but the second lead wiring 22C and the second external electrode 40C can also have the same structure.

[0141] (Manufacturing Method of Inductor Component 1C)

[0142] Next, an example of a method for manufacturing the inductor component 1C will be described. Note that the method for manufacturing the inductor component 1C is not limited to the following method, and other manufacturing methods may be used.

[0143] The method for manufacturing the inductor component 1C can be performed in the same manner as the method for manufacturing the inductor component 1. However, in the inductor component 1C, the lamination direction of the insulating paste is the Z-axis direction.

[0144] In addition, the present disclosure is not limited to the above-mentioned embodiment, and the design can be changed within the scope that does not deviate from the gist of the present disclosure. For example, various combinations of the characteristic points of each of the first to fourth embodiments are also possible.

[0145] The present disclosure includes the following aspects.

[0146] <1>

[0147] An inductor component, comprising:

[0148] green body;

[0149] A coil is disposed in the blank; and

[0150] The first external electrode and the second external electrode are provided on the above-mentioned body and are electrically connected to the above-mentioned coil.

[0151] The coil has a winding portion wound in a spiral shape along an axial direction.

[0152] The coil comprises: the winding portion; and a first lead wiring and a second lead wiring connecting one end and the other end of the winding portion to the first external electrode and the second external electrode,

[0153] At least one of the first external electrode and the second external electrode has an embedded portion embedded in the body.

[0154] At least one of the first lead wiring and the second lead wiring has: a connection portion connected to the winding portion; and a bent portion bent from the connection portion toward the embedded portion.

[0155] When projecting along the above axis,

[0156] The bent portion has a concave shape, and a length dimension L1 of the bent portion on a contact surface between the embedded portion and the lead wiring is larger than a wiring width W1 of the connecting portion.

[0157] The length dimension L1 is larger than a height dimension D1 of the embedded portion in a direction perpendicular to the contact surface.

[0158] <2>

[0159] The inductor component according to <1>, wherein:

[0160] When projected in the direction along the axis, a maximum height dimension D2 of the curved portion in a direction parallel to a height dimension D1 of the embedded portion is larger than the height dimension D1.

[0161] <3>

[0162] The inductor component according to <2>, wherein:

[0163] An increasing rate of the wiring width of the bent portion increases from a contact surface between the connection portion and the bent portion toward a contact surface between the embedded portion and the bent portion.

[0164] <4>

[0165] The inductor component according to <2> or <3>, wherein:

[0166] When projected along the direction of the axis, the contact surface between the embedded portion and the curved portion has, in order: a first contact point a1 having the maximum height dimension D2, a second contact point a2 having a height dimension D3 which is half of the maximum height dimension D2, and a third contact point a3 where the surface of the curved portion contacts the embedded portion.

[0167] A length dimension L3 along a contact surface between the embedded portion and the curved portion from the second contact point a2 to the third contact point a3 is greater than a length dimension L2 along a contact surface between the embedded portion and the curved portion from the first contact point a1 to the second contact point a2.

[0168] <5>

[0169] The inductor component according to any one of <1> to <4>, wherein:

[0170] The length dimension L1 is 10 μm or more.

[0171] <6>

[0172] The inductor component according to any one of <1> to <5>, wherein:

[0173] When projected along the axis, the ratio of the length dimension L1 of the portion facing the contact surface between the embedded portion and the bent portion to the length dimension L of the portion of the embedded portion exposed on the surface of the blank is 1 / 8 or more and 2 / 3 or less.

[0174] <7>

[0175] The inductor component according to any one of <1> to <6>, wherein:

[0176] At least one of the first external electrode and the second external electrode further includes a plating layer covering at least a portion of a portion of the embedded portion exposed on the surface of the body,

[0177] The above-mentioned plating layer contains Ni,

[0178] The first lead wiring and the embedded portion do not contain Ni.

[0179] <8>

[0180] The inductor component according to any one of <1> to <7>, wherein:

[0181] The coil has an outer peripheral surface on the inner diameter side and an outer peripheral surface on the outer diameter side opposite to the inner diameter.

[0182] When projected along the axis, at least one of the outer peripheral surface on the inner diameter side and the outer peripheral surface on the outer diameter side of the curved portion has a rounded shape.

[0183] The rounded shape has a rounded corner radius of 10 μm or more.

[0184] <9>

[0185] The inductor component according to any one of <1> to <8>, wherein:

[0186] The height dimension D1 of the embedded portion is 20 μm or less.

[0187] <10>

[0188] The inductor component according to any one of <1> to <9>, wherein:

[0189] A height dimension D4 of the plated layer in a direction parallel to the height dimension D1 is 10 μm or less.

[0190] <11>

[0191] The inductor component according to any one of <1> to <10>, wherein:

[0192] The blank comprises: a first end face and a second end face opposite to each other; a first side face and a second side face opposite to each other; a bottom face connected between the first end face and the second end face and between the first side face and the second side face; and a top face opposite to the bottom face.

[0193] The axis is orthogonal to the first side surface and the second side surface,

[0194] The first external electrode is formed continuously from the first end surface to the bottom surface,

[0195] The second external electrode is formed continuously from the second end surface to the bottom surface.

[0196] <12>

[0197] The inductor component according to <11>, wherein:

[0198] The coil has an outer peripheral surface on the inner diameter side and an outer peripheral surface on the outer diameter side opposite to the inner diameter.

[0199] When projected in the direction along the axis, the outer peripheral surface of the curved portion on the inner diameter side describes a rounded shape.

[0200] <13>

[0201] The inductor component according to any one of <1> to <10>, wherein:

[0202] The blank comprises: a first end face and a second end face opposite to each other; a first side face and a second side face opposite to each other; a bottom face connected between the first end face and the second end face and between the first side face and the second side face; and a top face opposite to the bottom face.

[0203] The axis is orthogonal to the first side surface and the second side surface,

[0204] The first external electrode and the second external electrode are disposed on the bottom surface.

[0205] <14>

[0206] The inductor component according to <13>, wherein:

[0207] The coil has an outer peripheral surface on the inner diameter side and an outer peripheral surface on the outer diameter side opposite to the inner diameter.

[0208] When projected in the direction of the axis, both the outer peripheral surface on the inner diameter side and the outer peripheral surface on the outer diameter side of the curved portion are rounded.

[0209] <15>

[0210] The inductor component according to any one of <1> to <10>, wherein:

[0211] The blank comprises: a first end face and a second end face opposite to each other; a first side face and a second side face opposite to each other; a bottom face connected between the first end face and the second end face and between the first side face and the second side face; and a top face opposite to the bottom face.

[0212] The axis is perpendicular to the bottom surface and the top surface,

[0213] The first external electrode is disposed on the first end surface.

[0214] The second external electrode is disposed on the second end surface.

Claims

1. An inductor component, wherein: have: green body; A coil is disposed in the blank; and A first external electrode and a second external electrode are disposed on the body and electrically connected to the coil. The coil has a winding portion wound in a spiral shape along an axial direction. The coil includes: the winding portion; and a first lead wiring and a second lead wiring that connect one end and the other end of the winding portion to the first external electrode and the second external electrode, At least one of the first external electrode and the second external electrode has an embedded portion embedded in the body, At least one of the first lead wiring and the second lead wiring has: a connection portion connected to the winding portion; and a bent portion bent from the connection portion toward the embedded portion. When projecting along the axis, The bent portion has a concave shape, and a length dimension L1 of the bent portion on a contact surface between the embedded portion and the lead wiring is larger than a wiring width W1 of the connecting portion. The length dimension L1 is larger than a height dimension D1 of the embedded portion in a direction perpendicular to the contact surface.

2. The inductor component according to claim 1, wherein When projected in the direction along the axis, a maximum height dimension D2 of the curved portion in a direction parallel to a height dimension D1 of the embedded portion is larger than the height dimension D1.

3. The inductor component according to claim 2, wherein: An increasing rate of the wiring width of the bent portion increases from a contact surface between the connection portion and the bent portion toward a contact surface between the embedded portion and the bent portion.

4. The inductor component according to claim 2 or 3, wherein: When projected along the axis, the contact surface between the embedded portion and the curved portion has, in order: a first contact point a1 having the maximum height dimension D2, a second contact point a2 having a height dimension D3 which is half of the maximum height dimension D2, and a third contact point a3 where the surface of the curved portion contacts the embedded portion. A length dimension L3 along a contact surface between the embedded portion and the curved portion from the second contact point a2 to the third contact point a3 is greater than a length dimension L2 along a contact surface between the embedded portion and the curved portion from the first contact point a1 to the second contact point a2.

5. The inductor component according to any one of claims 1 to 4, wherein: The length dimension L1 is greater than or equal to 10 μm.

6. The inductor component according to any one of claims 1 to 5, wherein: When projected along the axis, the ratio of the length dimension L1 of the portion facing the contact surface between the embedded portion and the bent portion to the length dimension L of the portion of the embedded portion exposed on the surface of the blank is 1 / 8 or more and 2 / 3 or less.

7. The inductor component according to any one of claims 1 to 6, wherein: At least one of the first external electrode and the second external electrode further includes a plating layer covering at least a portion of a portion of the embedded portion exposed on the surface of the body, The plating layer comprises Ni, The first lead wiring and the embedded portion do not contain Ni.

8. The inductor component according to any one of claims 1 to 7, wherein: The coil has an outer peripheral surface on the inner diameter side and an outer peripheral surface on the outer diameter side opposite to the inner diameter. When projected along the axis, at least one of the outer peripheral surface on the inner diameter side and the outer peripheral surface on the outer diameter side of the curved portion has a rounded shape. The rounded corner shape has a rounded corner radius of 10 μm or more.

9. The inductor component according to any one of claims 1 to 8, wherein: The height dimension D1 of the embedded portion is 20 μm or less.

10. The inductor component according to any one of claims 1 to 9, wherein: A height dimension D4 of the plating layer in a direction parallel to the height dimension D1 is 10 μm or less.

11. The inductor component according to any one of claims 1 to 10, wherein: The blank comprises: a first end face and a second end face opposite to each other; a first side face and a second side face opposite to each other; a bottom face connected between the first end face and the second end face and between the first side face and the second side face; and a top face opposite to the bottom face. The axis is orthogonal to the first side and the second side, The first external electrode is formed continuously from the first end surface to the bottom surface, The second external electrode is formed continuously from the second end surface to the bottom surface.

12. The inductor component according to claim 11, wherein The coil has an outer peripheral surface on the inner diameter side and an outer peripheral surface on the outer diameter side opposite to the inner diameter. When projected along the axial direction, the outer peripheral surface of the curved portion on the inner diameter side describes a rounded shape.

13. The inductor component according to any one of claims 1 to 10, wherein: The blank comprises: a first end face and a second end face opposite to each other; a first side face and a second side face opposite to each other; a bottom face connected between the first end face and the second end face and between the first side face and the second side face; and a top face opposite to the bottom face. The axis is orthogonal to the first side and the second side, The first external electrode and the second external electrode are disposed on the bottom surface.

14. The inductor component according to claim 13, wherein The coil has an outer peripheral surface on the inner diameter side and an outer peripheral surface on the outer diameter side opposite to the inner diameter. When projected along the axial direction, both the outer peripheral surface on the inner diameter side and the outer peripheral surface on the outer diameter side of the curved portion describe a rounded shape.

15. The inductor component according to any one of claims 1 to 10, wherein: The blank comprises: a first end face and a second end face opposite to each other; a first side face and a second side face opposite to each other; a bottom face connected between the first end face and the second end face and between the first side face and the second side face; and a top face opposite to the bottom face. The axis is orthogonal to the bottom surface and the top surface, The first external electrode is disposed on the first end surface, The second external electrode is disposed on the second end surface.

Images