Inductor components

Abstract

The present invention provides an inductor component that suppresses cracking and other damage while also suppressing a decrease in Q characteristics. [Solution] The inductor component 1A comprises a base body 10, a coil 20 wound spirally inside the base body along the coil axis direction parallel to the width direction W, and first and second external electrodes 30a and 30b exposed on the surface of the base body. The surface of the base body includes a bottom surface 12b parallel to the coil axis direction and a top surface 12a opposite the bottom surface in the height direction perpendicular to the coil axis direction. The coil consists of a plurality of coil wirings 21 extending in a direction perpendicular to the coil axis direction and arranged at different positions in the coil axis direction, and electrically connected. When viewed from the coil axis direction, the plurality of coil wirings have a straight section 23 and a curved section 24, and at least one curved section has a notch 51 in part in the coil axis direction, and the wiring thickness in the notch in the coil axis direction is smaller than the wiring thickness in the straight section in the coil axis direction.

Description

Technical Field

[0001] The present invention relates to an inductor component.

Background Art

[0002] Patent Document 1 discloses a method for manufacturing an inductor component, including steps of preparing a photosensitive insulating paste and a conductive paste containing a filler material made of quartz, a glass material, and a resin material; applying the insulating paste to form a first insulating layer; exposing the first insulating layer with a first portion of the first insulating layer shielded by a mask; removing the first portion of the first insulating layer to form a groove having a groove depth greater than the groove width at a position corresponding to the first portion; applying the conductive paste into the groove to form a coil conductor layer in the groove; and applying the insulating paste on the first insulating layer and on the coil conductor layer to form a second insulating layer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the method for manufacturing an inductor component described in Patent Document 1, the aspect ratio and the cross-sectional area of the coil conductor layer can be increased, so that the coil characteristics can be improved.

[0005] Multilayer inductors are often manufactured by sintering a laminate made of metal paste and insulating paste. However, the coefficient of thermal expansion differs between the wiring material, which is mainly composed of metal, and the insulating material, which is mainly composed of ceramic or magnetic material. As the wiring thickness in the lamination direction increases, as in the inductor component manufactured by the manufacturing method described in Patent Document 1, the wiring volume occupied by the insulating layer in any given space increases, so the residual stress generated during the cooling process after sintering increases, and the resistance to external impact decreases. This decrease in resistance to external impact leads to the problem that cracks, chips, and other defects (hereinafter also referred to as cracks, etc.) may occur in the product.

[0006] Furthermore, reducing integrated stress is effective in suppressing the decrease in resistance to external shocks. This can be achieved by reducing the volume of a portion of the coil wiring, but this presents the problem of a decrease in Q characteristics (Q value) due to the reduction in the cross-sectional area of ​​the coil wiring.

[0007] This invention was made to solve the above-mentioned problems, and aims to provide an inductor component that can suppress the occurrence of cracks and other damage while suppressing a decrease in Q characteristics. [Means for solving the problem]

[0008] The inductor component of the present invention comprises a base body, a coil provided inside the base body and wound spirally along the coil axis direction, a first external electrode and a second external electrode exposed on the surface of the base body, a first lead wire provided inside the base body and electrically connecting one end of the coil to the first external electrode, and a second lead wire provided inside the base body and electrically connecting the other end of the coil to the second external electrode, wherein the base body includes an insulator, the surface of the base body includes a mounting surface parallel to the coil axis direction and a top surface opposite to the mounting surface in the height direction perpendicular to the coil axis direction, and the first external electrode and the second external electrode are at least Both are exposed on the mounting surface of the above-mentioned body so as to be separated from each other, and the coil includes a plurality of coil wirings, each of which is electrically connected, and the plurality of coil wirings extend in a direction perpendicular to the coil axis direction and are electrically connected to a plurality of coil wirings that are arranged at different positions in the coil axis direction, and the plurality of coil wirings have a straight portion and a curved portion when viewed from the coil axis direction, and at least one of the curved portions has a notch in part in the coil axis direction, and the wiring thickness in the coil axis direction in the notch is smaller than the wiring thickness in the coil axis direction in the straight portion. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide an inductor component that can suppress the occurrence of cracks and other damage while suppressing a decrease in Q characteristics. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a schematic perspective view showing an example of an inductor component according to Embodiment 1 of the present invention. [Figure 2] Figure 2 is a schematic exploded perspective view showing an example of the inductor component shown in Figure 1. [Figure 3] Figure 3 is a schematic plan view showing an example of the inductor component shown in Figure 1, viewed from the direction of the coil axis. [Figure 4]Figure 4 shows the distribution of residual stress in a typical inductor component after firing. [Figure 5] Figure 5 shows the current density distribution flowing through a coil in a typical inductor component. [Figure 6] Figure 6 is a schematic cross-sectional view showing an example of a cross-section along the line segment a1-a2 of the inductor component shown in Figure 1. [Figure 7] Figure 7 is a schematic perspective view showing another example (modification 1) of the inductor component shown in Figure 1. [Figure 8] Figure 8 is a schematic cross-sectional view showing an example of a cross-section along the line segment b1-b2 of the inductor component shown in Figure 7. [Figure 9] Figure 9 is a schematic perspective view showing another example (modification 2) of the inductor component shown in Figure 1. [Figure 10] Figure 10 is a schematic cross-sectional view showing an example of a cross-section along the line segment c1-c2 of the inductor component shown in Figure 9. [Figure 11] Figure 11 shows the surface density distribution of high-frequency current flowing through a coil in a typical inductor component. [Figure 12] Figure 12 is a schematic perspective view showing another example (modification 3) of the inductor component shown in Figure 1. [Figure 13] Figure 13 is a schematic perspective view showing an example of an inductor component according to Embodiment 2 of the present invention. [Figure 14] Figure 14 is a schematic plan view showing an example of the inductor component shown in Figure 13, viewed from the direction of the coil axis. [Figure 15] Figure 15 is a schematic plan view showing another example (modification 1) of the inductor component shown in Figure 13, viewed from the coil axis direction. [Figure 16] Figure 16 is a schematic plan view showing an example of an inductor component according to Embodiment 3 of the present invention. [Figure 17] Figure 17 is a schematic plan view showing another example (modification example 1) of the inductor component shown in Figure 16. [Figure 18]FIG. 18 is a perspective view schematically showing another example of the inductor component shown in FIG. 1. [Figure 19] FIG. 19 is a perspective view schematically showing another example of the inductor component shown in FIG. 7. [Figure 20] FIG. 20 is a perspective view schematically showing another example of the inductor component shown in FIG. 7.

MODE FOR CARRYING OUT THE INVENTION

[0011] Hereinafter, the inductor component of the present invention will be described. Note that the present invention is not limited to the following configurations, and may be appropriately changed without departing from the gist of the present invention. Also, a combination of a plurality of the individual preferred configurations described below is also the present invention.

[0012] Each of the embodiments shown below is an exemplification, and it is needless to say that partial substitution or combination of the configurations shown in different embodiments is possible. In the following embodiments after the second embodiment, the description of the matters common to the first embodiment will be omitted, and the different points will be mainly described. In particular, the same operational effects due to the same configurations will not be sequentially mentioned for each embodiment.

[0013] In the following description, when not particularly distinguishing each embodiment, it is simply referred to as "the inductor component of the present invention".

[0014] The drawings shown below are schematic diagrams, and their dimensions, scales of aspect ratios of length and width, etc. may be different from those of actual products.

[0015] In this specification, terms indicating the relationship between elements (for example, "parallel", "perpendicular", "orthogonal", etc.) and terms indicating the shape of elements do not only mean the exact strict aspect, but also mean a substantially equivalent range, for example, a range including a difference of about several percent.

[0016] The inductor component of the present invention comprises a base body, a coil provided inside the base body and wound spirally along the coil axis direction, a first external electrode and a second external electrode exposed on the surface of the base body, a first lead wire provided inside the base body and electrically connecting one end of the coil to the first external electrode, and a second lead wire provided inside the base body and electrically connecting the other end of the coil to the second external electrode, wherein the base body includes an insulator, the surface of the base body includes a mounting surface parallel to the coil axis direction and a top surface opposite to the mounting surface in the height direction perpendicular to the coil axis direction, and the first external electrode and the second external electrode are at least Both are exposed on the mounting surface of the above-mentioned body so as to be separated from each other, and the coil includes a plurality of coil wirings, each of which is electrically connected, and the plurality of coil wirings extend in a direction perpendicular to the coil axis direction and are electrically connected to a plurality of coil wirings that are arranged at different positions in the coil axis direction, and the plurality of coil wirings have a straight portion and a curved portion when viewed from the coil axis direction, and at least one of the curved portions has a notch in part in the coil axis direction, and the wiring thickness in the coil axis direction in the notch is smaller than the wiring thickness in the coil axis direction in the straight portion.

[0017] [Embodiment 1] Figure 1 is a schematic perspective view showing an example of an inductor component according to Embodiment 1 of the present invention.

[0018] The inductor component 1A shown in Figure 1 comprises a base body 10, a coil 20, a first external electrode 30a, a second external electrode 30b, a first lead wire 22a, and a second lead wire 22b.

[0019] In this specification, the length direction, height direction, and width direction are defined by L, T, and W, respectively, as shown in Figure 1, etc. Here, the length direction L, the height direction T, and the width direction W are orthogonal to each other.

[0020] As shown in Figure 1, in the inductor component 1A, the surface of the base body 10 includes end faces 11a and 11b that are in the length direction L, a top surface 12a and a bottom surface 12b that are in the height direction T, and side surfaces 13a and 13b that are in the width direction W. In the inductor component 1A, the width direction W is parallel to the coil axis direction of the coil 20. That is, in the inductor component 1A, the surface of the base body 10 includes a bottom surface 12b that is parallel to the coil axis direction, and a top surface 12a that is in the height direction T which is perpendicular to the coil axis direction and is opposite to the bottom surface 12b.

[0021] In this embodiment, unless otherwise specified, the coil axis direction is parallel to the width direction W.

[0022] In the inductor component 1A, the bottom surface 12b of the base body 10 is the mounting surface. More specifically, the bottom surface 12b of the base body 10 is the mounting surface that faces the mounting target (e.g., a circuit board) when the inductor component 1A is mounted. Therefore, in the inductor component 1A, the mounting surface of the base body 10, that is, the bottom surface 12b of the base body 10, is parallel to the coil axis direction.

[0023] At least one of the surfaces of the base body 10, namely the end face 11a, end face 11b, top face 12a, bottom face 12b, side face 13a, and side face 13b, may be marked to facilitate identification of each face.

[0024] The end faces 11a and 11b of the base body 10 do not need to be strictly perpendicular to the length direction L. Also, the top face 12a and bottom face 12b of the base body 10 do not need to be strictly perpendicular to the height direction T. Furthermore, the side faces 13a and 13b of the base body 10 do not need to be strictly perpendicular to the width direction W.

[0025] As shown in Figure 1, the base body 10 is, for example, a rectangular parallelepiped.

[0026] In this specification, a rectangular parallelepiped shape is sufficient if it is substantially rectangular in shape, and includes, for example, a roughly rectangular parallelepiped shape in which the corners and edges are rounded, as described later.

[0027] It is preferable that the base body 10 has rounded corners and edges. The corners of the base body 10 are the parts where the three faces of the base body 10 intersect. The edges of the base body 10 are the parts where the two faces of the base body 10 intersect.

[0028] Figure 2 is a schematic exploded perspective view showing an example of the inductor component shown in Figure 1.

[0029] The base body 10 includes an insulator. In the example shown in Figure 2, the insulator is made up of multiple insulating layers stacked in the direction of the coil axis.

[0030] In the example shown in Figure 2, the multiple insulating layers include insulating layer 15a, insulating layer 15b, insulating layer 15c, insulating layer 15d, insulating layer 15e, insulating layer 15f, insulating layer 15g, insulating layer 15h, and insulating layer 15i. The insulating layers 15a, 15b, 15c, 15d, 15e, 15f, 15g, 15h, and 15i are stacked sequentially from side surface 13b to side surface 13a of the base body 10 in the coil axis direction.

[0031] Furthermore, multiple insulating layers may be integrated, and their boundaries may not be clearly visible.

[0032] Furthermore, the multiple insulating layers may include at least one additional insulating layer in addition to the insulating layers described above. For example, at least one insulating layer may be present between insulating layer 15a and insulating layer 15b in the coil axis direction. Also, at least one insulating layer may be present between insulating layer 15h and insulating layer 15i in the coil axis direction.

[0033] Examples of insulating materials that constitute the insulator (insulating layer) include glass materials mainly composed of borosilicate glass, ceramic materials, organic materials such as epoxy resins, fluororesins, and polymer resins, and composite materials such as glass epoxy resins. Among insulating materials, materials with low dielectric constant and dielectric loss are particularly preferred.

[0034] The insulating materials that make up the multiple insulating layers may be the same as each other, may be different from each other, or may be different in some respects.

[0035] The thicknesses of the multiple insulating layers in the coil axis direction may be the same, different, or partially different.

[0036] As shown in Figure 1, the coil 20 is located inside the base body 10 and is wound spirally along the coil axis.

[0037] The direction of the coil axis of coil 20 is the direction in which the coil axis CA of coil 20 extends, and as described above, it is parallel to the bottom surface 12b, which is the mounting surface of the base body 10. Also, the direction of the coil axis of coil 20 is parallel to the stacking direction.

[0038] As shown in Figures 1 and 2, the coil 20 includes a plurality of coil wirings 21, each electrically connected, and the plurality of coil wirings 21 extend in a direction perpendicular to the coil axis direction and are electrically connected to each other at different positions in the coil axis direction.

[0039] In the inductor component 1A, the two coil wires, coil wire 21a and coil wire 21b, are positioned at different locations relative to each other in the coil axis direction.

[0040] In the example shown in Figure 2, the coil wiring 21a is formed by stacking coil conductor layers 121aa, 121ab, and 121ac in the direction of the coil axis. The coil wiring 21b is formed by stacking coil conductor layers 121ba, 121bb, and 121bc in the direction of the coil axis.

[0041] In the coil wiring 21a, in addition to the coil conductor layer described above, at least one other coil conductor layer may be further laminated in the coil axial direction. Similarly, in the coil wiring 21b, in addition to the coil conductor layer described above, at least one other coil conductor layer may be further laminated in the coil axial direction.

[0042] Furthermore, at least one other coil wiring may exist between coil wiring 21a and coil wiring 21b in the coil axial direction.

[0043] Examples of conductive materials that make up the coil wiring 21 include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0044] The conductive materials constituting the multiple coil wirings 21 may be the same as each other, different from each other, or partially different.

[0045] The thickness of the multiple coil wirings 21 in the coil axis direction may be the same as, different from, or partially different.

[0046] For multiple coil wirings 21, the thickness in the direction perpendicular to the coil axis direction and the direction in which the coil wiring 21 extends, that is, the thickness in the width direction w1 (see Figure 1) of the coil wiring 21, may be the same as each other, may be different from each other, or may be different in some parts.

[0047] Among the multiple coil wirings 21, adjacent coil wirings 21 in the coil axis direction may be electrically connected via via conductors that penetrate the insulating layer between the adjacent coil wirings 21 in the coil axis direction, or they may be directly connected without via conductors. In other words, the coil 20 may consist of multiple coil wirings 21 arranged at different positions in the coil axis direction that are electrically connected via via conductors, or they may be directly connected without via conductors.

[0048] In the example shown in Figure 2, coil wiring 21a and coil wiring 21b are electrically connected via a via conductor 29a that penetrates the insulating layer 15e in the direction of the coil axis.

[0049] In the example shown in Figure 2, the via conductor 29a consists of a via conductor layer 129aa.

[0050] In the via conductor 29a, at least one other via conductor layer may be laminated in addition to the via conductor layer 129aa in the direction of the coil axis.

[0051] The via conductor 29a may have a single-layer structure or a multi-layer structure.

[0052] Examples of conductive materials constituting the via conductor 29a include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0053] Figure 3 is a schematic plan view showing an example of the inductor component shown in Figure 1, viewed from the direction of the coil axis.

[0054] As shown in Figure 3, the multiple coil wirings 21 have straight sections 23 and curved sections 24 when viewed from the direction of the coil axis.

[0055] When viewed from the direction of the coil axis, the coil 20 only needs to have a shape that includes straight sections and curved sections, such that multiple coil wirings 21 arranged at different positions have straight sections 23 and curved sections 24. For example, it may be a polygonal shape as shown in Figure 3, or it may be a track shape or heart shape as described later.

[0056] As shown in Figure 1, one end of the coil 20 is electrically connected to the first external electrode 30a via the first lead wire 22a.

[0057] In the example shown in Figure 2, the first lead wiring 22a consists of a first lead conductor layer 122aa, a first lead conductor layer 122ab, and a first lead conductor layer 122ac.

[0058] In the first lead wiring 22a, in addition to the first lead conductor layer described above, at least one other lead conductor layer may be laminated in the coil axial direction.

[0059] The first lead wiring 22a may have a single-layer structure or a multi-layer structure.

[0060] As shown in Figure 1, the other end of the coil 20 is electrically connected to the second external electrode 30b via the second lead wire 22b.

[0061] In the example shown in Figure 2, the second lead wiring 22b consists of a second lead conductor layer 122ba, a second lead conductor layer 122bb, and a second lead conductor layer 122bc.

[0062] In the second lead wiring 22b, in addition to the second lead conductor layer described above, at least one other lead conductor layer may be laminated in the coil axial direction.

[0063] The second lead wiring 22b may have a single-layer structure or a multi-layer structure.

[0064] Examples of conductive materials that make up the lead-out wiring include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0065] The conductive materials constituting the first lead wiring 22a and the second lead wiring 22b may be the same or different.

[0066] In this specification, wiring that does not overlap the circumference of the coil (i.e., extends beyond the circumference of the coil) when viewed from the direction of the coil axis is defined as lead wiring.

[0067] As shown in Figure 1, the first external electrode 30a is exposed on the surface of the substrate 10.

[0068] As shown in Figure 1, it is preferable that the first external electrode 30a is exposed to at least the bottom surface 12b of the base body 10.

[0069] In the example shown in Figure 1, the first external electrode 30a extends from a portion of the bottom surface 12b of the base body 10 to a portion of the end surface 11a. In other words, in the example shown in Figure 1, the first external electrode 30a is exposed not only on a portion of the bottom surface 12b of the base body 10, but also on a portion of the end surface 11a of the base body 10.

[0070] The first external electrode 30a may be exposed only on the bottom surface 12b of the base body 10.

[0071] In the example shown in Figure 2, the first external electrode 30a is formed by stacking the first external conductor layers 130aa, 130ab, 130ac, 130ad, 130ae, 130af, and 130ag in the direction of the coil axis.

[0072] In the first external electrode 30a, in addition to the first external conductor layer described above, at least one other external conductor layer may be further laminated in the coil axial direction.

[0073] The first external electrode 30a may have a single-layer structure or a multi-layer structure.

[0074] As shown in Figure 1, the second external electrode 30b is exposed on the surface of the substrate 10.

[0075] As shown in Figure 1, it is preferable that the second external electrode 30b is exposed to at least the bottom surface 12b of the base body 10.

[0076] In the example shown in Figure 1, the second external electrode 30b extends from a portion of the bottom surface 12b of the base body 10 to a portion of the end surface 11b. In other words, in the example shown in Figure 1, the second external electrode 30b is exposed not only on a portion of the bottom surface 12b of the base body 10 but also on a portion of the end surface 11b of the base body 10.

[0077] The second external electrode 30b may be exposed only on the bottom surface 12b of the base body 10.

[0078] In the example shown in Figure 2, the second external electrode 30b is formed by stacking the second external conductor layers 130ba, 130bb, 130bc, 130bd, 130be, 130bf, and 130bg in the direction of the coil axis.

[0079] In the second external electrode 30b, in addition to the second external conductor layer described above, at least one other external conductor layer may be further laminated in the coil axis direction.

[0080] The second external electrode 30b may have a single-layer structure or a multi-layer structure.

[0081] As described above, it is preferable that the first external electrode 30a and the second external electrode 30b are exposed so as to be separated from each other at least on the bottom surface 12b of the base body 10. In the example shown in Figure 1, the first external electrode 30a and the second external electrode 30b are provided so as to be separated from each other in a direction perpendicular to the coil axis direction (here, the length direction L).

[0082] Furthermore, if the first external electrode 30a and the second external electrode 30b are exposed on the bottom surface 12b of the base body 10, which is the mounting surface, the mountability of the inductor component 1A is improved.

[0083] In the example shown in Figure 1, the dimension of the first external electrode 30a in the coil axis direction is smaller than the dimension of the base body 10 in the coil axis direction.

[0084] The dimensions of the first external electrode 30a in the coil axis direction may be the same as the dimensions of the base body 10 in the coil axis direction.

[0085] In the example shown in Figure 1, the dimension of the second external electrode 30b in the coil axis direction is smaller than the dimension of the base body 10 in the coil axis direction.

[0086] Furthermore, the dimensions of the second external electrode 30b in the coil axis direction may be the same as the dimensions of the base body 10 in the coil axis direction.

[0087] Examples of conductive materials constituting the first external electrode 30a and the second external electrode 30b include Ag, Au, Cu, Pd, Ni, Al, and alloys containing at least one of these metals.

[0088] The first external electrode 30a may have, in order from the coil 20 side, a base electrode containing the conductive material described above (for example, Ag), a Ni-plated electrode, and a Sn-plated electrode. In this case, the base electrode of the first external electrode 30a may form a surface integral with the surface of the base body 10 (in Figure 1, the end face 11a and the bottom face 12b of the base body 10), and the Ni-plated electrode and the Sn-plated electrode may protrude from the surface of the base body 10 (in Figure 1, the end face 11a and the bottom face 12b of the base body 10) so as to cover the base electrode.

[0089] The second external electrode 30b may have, in order from the coil 20 side, a base electrode containing the conductive material described above (for example, Ag), a Ni-plated electrode, and a Sn-plated electrode. In this case, the base electrode of the second external electrode 30b may form a surface integral with the surface of the base body 10 (in Figure 1, the end face 11b and the bottom face 12b of the base body 10), and the Ni-plated electrode and the Sn-plated electrode may protrude from the surface of the base body 10 (in Figure 1, the end face 11b and the bottom face 12b of the base body 10) so as to cover the base electrode.

[0090] The conductive materials constituting the first external electrode 30a and the second external electrode 30b may be the same or different.

[0091] As shown in Figure 1, at least one curved section 24 has a notch 51 in a portion of it in the direction of the coil axis. The wiring thickness in the direction of the coil axis in the notch 51 is smaller than the wiring thickness in the direction of the coil axis in the straight section 23.

[0092] Figure 4 shows the distribution of residual stress in a typical inductor component after firing.

[0093] As shown in Figure 4, after firing of the inductor component, particularly large stresses generally remain near the curved portion of the coil wiring (for example, the portion indicated by the arrow in Figure 4). In the inductor component 1A, a notch 51 is provided in a portion of the coil axis direction of at least one curved portion 24, and the wiring thickness in the coil axis direction in the notch 51 is made smaller than the wiring thickness in the coil axis direction in the straight portion 23. This reduces the volume of the coil wiring 21, especially in the curved portion 24 where residual stress after firing is large, and reduces the integral stress applied to any region. As a result, the decrease in external impact resistance is suppressed in the inductor component 1A, and the occurrence of cracks and the like can be suppressed.

[0094] Figure 5 shows the density distribution of DC current flowing through a coil in a typical inductor component.

[0095] As shown in Figure 5, in general, in curved sections, current is concentrated on the inner circumference side where the current path is shortest (for example, the area enclosed by the dashed line in Figure 5), and only a portion of the cross-sectional area of ​​the coil wiring is effectively utilized. In inductor component 1A, by providing a notch 51 in the curved section 24, it is possible to suppress the decrease in Q characteristics due to the reduction in the cross-sectional area of ​​the coil wiring 21, while also suppressing the decrease in external shock resistance, compared to the case where the notch 51 is provided in the straight section 23 where the entire cross-sectional area of ​​the coil wiring 21 is effectively utilized.

[0096] Based on the above, inductor component 1A makes it possible to realize an inductor component that can suppress the occurrence of cracks and other damage while suppressing the deterioration of the Q characteristics.

[0097] In this specification, "wiring thickness in the coil axis direction at the notch" refers to the thickness of the coil wiring in the coil axis direction at which the notch is provided, and represents the thickness of the coil wiring in the region including the notch, i.e., the curved portion at which the notch is provided. Note that this "thickness of the coil wiring in the curved portion at which the notch is provided" may be the thickness t1 of any part separated by the notch 51, as shown in Figure 1, or it may be the sum of the thicknesses t1 of each part separated by the notch 51.

[0098] Furthermore, in this specification, "wiring thickness in the coil axis direction in a straight section" refers to the thickness in the coil axis direction of a coil wiring provided with a notch whose thickness is to be compared, and represents the thickness of the coil wiring in the straight section of that coil wiring (see thickness t2 in Figure 1).

[0099] In Figure 1, the thickness t1 of any portion separated by the notch 51 is smaller than the thickness t2 of the coil wiring in the straight section, and the sum of the thicknesses t1 of each portion separated by the notch 51 is also smaller than the thickness t2 of the coil wiring in the straight section.

[0100] Furthermore, in the inductor component of the present invention, the first lead wiring and the second lead wiring do not have notches.

[0101] As shown in Figure 3, when viewed from the coil axis direction, the coil 20 has a polygonal shape, and the straight section 23 has one first straight section 23a on the top surface side and one or more second straight sections 23b on the mounting surface side with respect to the center line of the height direction T of the base body 10, and further has a third straight section 23c connecting the first straight section 23a and the second straight section 23b, and the first straight section 23a and the second straight section 23b are parallel to the bottom surface 12b which is the mounting surface, and the curved section 24 has a first curved section 24a connecting the first straight section 23a and the third straight section 23c, and a second curved section 24b connecting any of the second straight sections 23b and the third straight section 23c, or between two second straight sections 23b. As a result, the coil wiring 21 can be drawn as large as possible inside the base body, the cross-sectional area of ​​the coil 20 is increased and the efficiency of acquiring the L value is improved.

[0102] Furthermore, in the inductor component 1A equipped with such a coil 20, as shown in Figure 1, at least one of the first curved portion 24a and the second curved portion 24b is provided with a notch 51 in a part in the coil axis direction, and it is preferable that the wiring thickness in the coil axis direction in the notch 51 is smaller than the wiring thickness in the coil axis direction in the straight portion 23. In the coil 20 with the shape shown in Figure 3, large residual stress is generated in the first curved portion 24a and the second curved portion 24b that connect adjacent straight portions 23, but by providing a notch 51 in this region as described above and reducing the wiring volume, the integral stress can be reduced, suppressing a decrease in impact resistance and preventing the occurrence of cracks in the product as a result.

[0103] More specifically, as shown in Figure 3, the multiple coil wirings 21 in the inductor component 1A have, for each turn of the coil 20, a straight section 23, which includes one first straight section 23a located on the top side with respect to the center line of the height direction T of the base body 10, three second straight sections 23b located on the mounting side, and two third straight sections 23c connecting the first straight sections 23a and the second straight sections 23b. The curved section 24 includes two first curved sections 24a connecting the first straight sections 23a and the third straight sections 23c, and four second curved sections 24b connecting any of the second straight sections 23b and the third straight sections 23c, or any two second straight sections 23b. The first straight sections 23a and the second straight sections 23b are parallel to the bottom surface 12b, which is the mounting surface. Furthermore, the first curved portion 24a of each coil wiring 21 is provided with a notch 51 in a portion of the coil axial direction (see Figure 1).

[0104] Figure 6 is a schematic cross-sectional view showing an example of a cross-section along the line segment a1-a2 of the inductor component shown in Figure 1.

[0105] As shown in Figures 1 and 6, in the inductor component 1A, the notch 51 is located in the middle of the curved portion 24 in the coil axis direction. By providing the notch 51 in the middle of the curved portion 24 in the coil axis direction, the thickness of the coil wiring 21 in the coil axis direction is divided through the notch 51. Therefore, the high integral stress region can be distributed while ensuring the total cross-sectional area of ​​the curved portion 24, thereby suppressing a decrease in Q characteristics and a decrease in external shock resistance.

[0106] As shown in Figure 2, the coil wiring 21a is formed by laminating coil conductor layers 121aa and 121ac, which do not have a notch 51, via a coil conductor layer 121ab having a notch 51 in the curved portion 24. In this way, multiple coil conductor layers without a notch 51 are connected to the curved portion 24 via a coil conductor layer having a notch 51, so that the notch 51 is located in the middle of the curved portion 24 in the coil axis direction.

[0107] Figure 7 is a schematic perspective view showing another example (modification 1) of the inductor component shown in Figure 1.

[0108] Figure 8 is a schematic cross-sectional view showing an example of a cross-section along the line segment b1-b2 of the inductor component shown in Figure 7.

[0109] As shown in Figures 7 and 8, in the inductor component 1B, the notch 51 is provided at the outer end of the body in the coil axis direction of the curved portion 24.

[0110] In inductor component 1B, by providing the notch 51 at the outer end of the base body in the coil axis direction of the curved portion 24, the integrated stress in the region close to the surface of the base body 10, which is susceptible to external shocks, is reduced. Therefore, compared to inductor component 1A, the decrease in resistance to external shocks can be further suppressed. In this case, it is preferable that the notch 51 be provided in the outermost coil wiring among the multiple coil wirings 21 in the coil axis direction.

[0111] Here, "outer end of the body in the coil axis direction" refers to the end closest to the surface of the body in the coil axis direction. For example, in Figure 8, the notch 51 is provided at the end closest to the side surface 13a in the W direction.

[0112] Figure 9 is a schematic perspective view showing another example (modification 2) of the inductor component shown in Figure 1.

[0113] Figure 10 is a schematic cross-sectional view showing an example of a cross-section along the line segment c1-c2 of the inductor component shown in Figure 9.

[0114] As shown in Figures 9 and 10, in the inductor component 1C, the notch 51 is provided at the inner end of the curved portion 24 in the coil axis direction.

[0115] Figure 11 shows the surface density distribution of high-frequency current flowing through a coil in a typical inductor component. Note that Figure 11 shows the results of a simulation performed at a frequency of 3 GHz.

[0116] As shown in Figure 11, generally, high-frequency current flows more in the coil 20 on the side closer to the elemental body in the coil axis direction. In inductor component 1C, by providing the notch 51 at the inner end of the elemental body in the coil axis direction of the curved portion 24, the volume of the coil wiring 21 can be reduced while reducing current reflection loss in the high-current-density section (for example, the part indicated by the arrow in Figure 11). Therefore, compared to inductor component 1A, the decrease in Q characteristics can be further suppressed while suppressing the decrease in external shock resistance. In this case, it is preferable that the notch 51 be provided in the outermost coil wiring among the multiple coil wirings 21 in the coil axis direction.

[0117] Here, "inner end of the body in the coil axis direction" refers to the end closest to the center of the body in the coil axis direction. For example, in Figure 10, the notch 51 is provided at the end closest to the center of the body in the W direction.

[0118] Figure 12 is a schematic perspective view showing another example (modification 3) of the inductor component shown in Figure 1.

[0119] As shown in Figure 12, in the inductor component 1D, the notch 51 is provided in the second curved portion 24b located on the mounting surface side. In Figure 12, the notch 51 is provided in the second curved portion 24b connecting two second straight portions 23b, but it may also be provided in the second curved portion 24b connected to the third straight portion 23c.

[0120] As shown in Figure 1, in the inductor component 1A, the notch 51 is provided in the first curved portion 24a located on the top surface side. By providing the notch 51 in the curved portion 24 located on the top surface side, the integrated stress in the area where the surface is not protected by the first external electrode 30a and the second external electrode 30b is reduced, and the decrease in the external impact resistance of that area can be suppressed.

[0121] Inductor components are generally subjected to external shocks during the sorting process when measurement terminals are pressed against them from the mounting side. In inductor component 1D, by providing a notch 51 in the curved portion 24 located on the mounting side, the integrated stress near the area where external shocks are applied during the sorting process is reduced, thereby suppressing a decrease in the external shock resistance of that area.

[0122] Furthermore, in an inductor component equipped with a coil 20 having the shape shown in Figure 3, a configuration in which a notch 51 is provided in the first curved portion 24a located on the top surface side, as in the inductor component 1A shown in Figure 1, and a configuration in which a notch 51 is provided in the second curved portion 24b located on the mounting surface side, as in the inductor component 1D shown in Figure 12, may be combined. That is, at least one notch 51 may be provided in both the first curved portion 24a and the second curved portion 24b.

[0123] Inductor component 1A is manufactured, for example, by the following method:

[0124] <Process for creating the mother stack> First, an insulating paste layer, which will later become the insulating layer 15a, is formed by repeatedly applying an insulating paste containing, for example, a glass material mainly composed of borosilicate glass, using screen printing or the like.

[0125] Next, a photosensitive conductive paste layer is formed on the insulating paste layer by coating it with a photosensitive conductive paste, for example, one with Ag as the main metal component, using screen printing or the like. Furthermore, the photosensitive conductive paste layer is irradiated with ultraviolet light or the like via a photomask, and then developed with an alkaline solution or the like to form a coil conductor layer, which will later become the coil conductor layer 121ba, an outer conductor layer, which will later become the first outer conductor layer 130aa and the second outer conductor layer 130ba, and a lead conductor layer, which will later become the second lead conductor layer 122ba, connected to the coil conductor layer and the outer conductor layer, at multiple locations on the insulating paste layer.

[0126] Furthermore, when forming the coil conductor layer, the lead conductor layer, and the outer conductor layer, instead of exposure using a photomask, for example, DI exposure (also called direct image exposure or direct writing) without a photomask may be performed.

[0127] Next, for example, by coating a photosensitive insulating paste with a screen print or the like, insulating paste layers that will later become insulating layers 15b and 15c are formed on the insulating paste layer that will later become insulating layer 15a. Furthermore, by irradiating the insulating paste layer that will later become insulating layer 15c with ultraviolet light or the like via a photomask and then developing it with an alkaline solution or the like, openings for the coil conductor layer, an outer conductor layer, and openings for the lead conductor layer connected to the openings for the coil conductor layer and the outer conductor layer are formed in the insulating paste layer that will later become insulating layer 15c. The openings for the coil conductor layer formed here overlap the coil conductor layer that will later become coil conductor layer 121ba, except for the area where the notch is provided, and have the same shape as the coil conductor layer that will later become coil conductor layer 121bb. The openings for the lead conductor layer formed here overlap the lead conductor layer that will later become the second lead conductor layer 122ba. The openings for the outer conductor layer formed here overlap with the outer conductor layers that will later become the first outer conductor layer 130aa and the second outer conductor layer 130ba.

[0128] Furthermore, when forming an insulating paste layer with an opening, instead of exposure using a photomask, for example, DI exposure without a photomask may be performed.

[0129] Next, a new photosensitive conductive paste layer is formed inside the opening and on top of the insulating paste layer, which will later become the insulating layer 15c, by coating a photosensitive conductive paste, for example, with Ag as the main metal component, using screen printing or the like. Furthermore, by irradiating the photosensitive conductive paste layer with ultraviolet light or the like via a photomask and then developing it with an alkaline solution or the like, a coil conductor layer, which will later become the coil conductor layer 121bb, is formed inside the opening for the coil conductor layer, and a coil conductor layer, which will later become the coil conductor layer 121bc, is formed connected to this coil conductor layer. Furthermore, a lead conductor layer, which will later become the second lead conductor layer 122bb, is formed inside the opening for the lead conductor layer, and a lead conductor layer, which will later become the second lead conductor layer 122bc, is formed connected to this lead conductor layer. Furthermore, an outer conductor layer, which will later become the first outer conductor layer 130ab, is formed inside the opening for the outer conductor layer and connected to the outer conductor layer, which will later become the first outer conductor layer 130aa, and an outer conductor layer, which will later become the first outer conductor layer 130ac, is formed on top of this outer conductor layer. Furthermore, an outer conductor layer, which will later become the second outer conductor layer 130bb, is formed inside the opening for the outer conductor layer, connected to the outer conductor layer that will later become the second outer conductor layer 130ba, and an outer conductor layer that will later become the second outer conductor layer 130bc is formed on this outer conductor layer.

[0130] Next, for example, by coating a photosensitive insulating paste with a screen print or the like, insulating paste layers that will later become insulating layers 15d and 15e are formed on the insulating paste layer that will later become insulating layer 15c. Furthermore, after irradiating the insulating paste layer that will later become insulating layer 15e with ultraviolet light or the like via a photomask, it is developed with an alkaline solution or the like to form via holes and openings for the outer conductor layer in the insulating paste layer that will later become insulating layer 15e. The via holes formed here overlap the ends of the coil conductor layer that will later become coil conductor layer 121bc and have the same shape as the via conductor layer that will later become via conductor layer 129aa. The openings for the outer conductor layer formed here overlap the outer conductor layers that will later become the first outer conductor layer 130ac and the second outer conductor layer 130bc.

[0131] Next, a new photosensitive conductive paste layer is formed inside the via holes and openings by coating a photosensitive conductive paste, for example, one with Ag as the main metal component, using screen printing or the like, on top of the insulating paste layer which will later become the insulating layer 15e. Furthermore, by irradiating the photosensitive conductive paste layer with ultraviolet light or the like via a photomask and then developing it with an alkaline solution or the like, a via conductor layer which will later become the via conductor layer 129aa is formed inside the via holes, and a coil conductor layer which will later become the coil conductor layer 121aa is formed connected to this via conductor layer. Furthermore, an outer conductor layer which will later become the first outer conductor layer 130ad is formed inside the openings, connected to an outer conductor layer which will later become the first outer conductor layer 130ac, and an outer conductor layer which will later become the first outer conductor layer 130ae is formed on top of this outer conductor layer. Furthermore, an outer conductor layer, which will later become the second outer conductor layer 130bd, is formed inside the opening, connected to the outer conductor layer that will later become the second outer conductor layer 130bc, and an outer conductor layer that will later become the second outer conductor layer 130be is formed on this outer conductor layer. Furthermore, a lead conductor layer, which will later become the first lead conductor layer 122aa, is formed on an insulating paste layer that will later become the insulating layer 15e, connected to the coil conductor layer that will later become the coil conductor layer 121aa and the outer conductor layer that will later become the first outer conductor layer 130ae.

[0132] Furthermore, when forming the via conductor layer and the outer conductor layer, instead of exposure using a photomask, for example, DI exposure without a photomask may be performed.

[0133] In the same manner as described above, the remaining coil conductor layer, lead conductor layer, and outer conductor layer are formed, while insulating paste layers, which will later become insulating layers 15f, 15g, and 15h, are formed.

[0134] Finally, an insulating paste layer, which will later become the insulating layer 15i, is formed by repeatedly applying an insulating paste containing, for example, a glass material mainly composed of borosilicate glass, using screen printing or the like.

[0135] Based on the above, the motherboard is fabricated.

[0136] The method for forming the conductor patterns of the coil conductor layer, lead conductor layer, via conductor layer, and outer conductor layer is not limited to the photolithography method described above. For example, it may be a method of printing and layering conductive paste using a screen printing plate provided with openings in the shape of the conductor pattern, or a method of forming a conductor film by sputtering, vapor deposition, or foil bonding, and then etching the conductor film to form the shape of the conductor pattern, or a method of forming a negative pattern by a semi-additive method, then forming a plating film, and then removing unnecessary parts of the plating film by etching or the like to form the shape of the conductor pattern.

[0137] When forming the conductor patterns of the coil conductor layer, lead conductor layer, via conductor layer, and outer conductor layer, a high aspect ratio can be achieved by forming the conductor patterns in multiple stages, thereby reducing losses due to resistance at high frequencies. The method for forming the conductor patterns in multiple stages is not particularly limited. For example, it may be a method of repeatedly stacking conductor patterns by repeating the process using the photolithography method as described above, or a method of repeatedly stacking conductor patterns formed by the semi-additive method, or a method of stacking conductor patterns formed by the semi-additive method and conductor patterns formed by etching a separately plated film in any order, or a method of further plating and growing a plated film formed by the semi-additive method.

[0138] The conductive material constituting the conductor patterns of the coil conductor layer, lead conductor layer, via conductor layer, and outer conductor layer is not limited to the photosensitive conductive paste having Ag or the like as its main metal component, but may also be a conductor containing metals such as Ag, Au, or Cu formed by methods such as sputtering, vapor deposition, foil bonding, or plating.

[0139] The method for forming the insulating paste layer is not limited to the photolithography method described above, but may also be, for example, a method of pressing a sheet made of insulating material, a method of spin-coating the insulating material, or a method of spray-coating the insulating material.

[0140] The method for forming an insulating paste layer with via holes and openings is not limited to the photolithography method described above. For example, an insulating film may be formed by methods such as pressing a sheet made of insulating material, spin-coating an insulating material, or spray-coating an insulating material, and then providing via holes and openings to the insulating film by laser processing, drilling, or the like.

[0141] The insulating material constituting the insulating paste layer is not limited to the glass material mainly composed of borosilicate glass as described above, but may also be, for example, ceramic materials, organic materials such as epoxy resins, fluororesins, and polymer resins, or composite materials such as glass epoxy resins. As the insulating material, materials with low dielectric constant and dielectric loss are particularly preferred.

[0142] <Process for forming the base body, coil, and external electrodes> First, the mother laminate is cut into multiple unfired laminates by dicing or other methods.

[0143] The unfired laminate has an insulating paste laminate section in which insulating paste layers are laminated, a coil conductor laminate section in which coil conductor layers are laminated such that adjacent coil conductor layers are electrically connected via via conductor layers, and an outer conductor laminate section in which outer conductor layers are laminated.

[0144] When separating the unfired laminate into individual pieces, for example, the outer conductor laminate is exposed at two locations on the bottom surface of at least the insulating paste laminate included in the cut surface of the unfired laminate.

[0145] Next, the laminate is produced by firing the unfired laminate.

[0146] When the unfired laminate is fired, the insulating paste layer becomes an insulating layer, and the insulating paste laminate becomes a base body 10. Also, when the unfired laminate is fired, the coil conductor layer becomes a coil wiring 21, and the coil conductor laminate becomes a coil 20. Furthermore, when the unfired laminate is fired, one of the two external conductor laminates becomes part of the first external electrode 30a, and the other becomes part of the second external electrode 30b.

[0147] Next, the resulting laminate may be subjected to a process such as barrel polishing to round off the corners and edges of the base body 10.

[0148] Finally, using the two fired outer conductor laminates as base electrodes, Ni-plated electrodes and Sn-plated electrodes are sequentially formed on the surface of each base electrode by plating. The thickness of the Ni-plated electrodes and Sn-plated electrodes is, for example, 2 μm or more and 10 μm or less, respectively.

[0149] In this way, a first external electrode 30a and a second external electrode 30b are formed, having a base electrode, a Ni-plated electrode, and a Sn-plated electrode in that order from the surface side of the base body 10. In this case, in the first external electrode 30a, the base electrode forms a surface integral with the surface of the base body 10 (in Figure 1, the end face 11a and the bottom face 12b of the base body 10), and the Ni-plated electrode and the Sn-plated electrode may protrude from the surface of the base body 10 (in Figure 1, the end face 11a and the bottom face 12b of the base body 10) so as to cover the base electrode. In the second external electrode 30b, the base electrode forms a surface integral with the surface of the base body 10 (in Figure 1, the end face 11b and the bottom face 12b of the base body 10), and the Ni-plated electrode and the Sn-plated electrode may protrude from the surface of the base body 10 (in Figure 1, the end face 11b and the bottom face 12b of the base body 10) so as to cover the base electrode.

[0150] The method for forming the external electrode is not limited to the method of applying a plating treatment to the external conductor laminate exposed on the cut surface of the unfired laminate (for example, at least the bottom surface of the insulating paste laminate) as described above. For example, the external conductor laminate may be exposed on the cut surface of the unfired laminate (for example, at least the bottom surface of the insulating paste laminate) as described above, and then the exposed portion of the external conductor laminate may be dipped in conductive paste, or a conductive paste film may be formed on the exposed portion of the external conductor laminate by sputtering, and then a plating treatment may be applied.

[0151] Based on the above, inductor component 1A is manufactured.

[0152] Inductor component 1A is manufactured, for example, in 0402 size (0.4mm x 0.2mm x 0.2mm). However, the size of inductor component 1A is not limited to 0402 size (0.4mm x 0.2mm x 0.2mm).

[0153] [Embodiment 2] Figure 13 is a schematic perspective view showing an example of an inductor component according to Embodiment 2 of the present invention.

[0154] As shown in Figure 13, the coil 20 in the inductor component 1E is composed of two layers of coil wiring: coil wiring 21a and coil wiring 21b.

[0155] Figure 14 is a schematic plan view showing an example of the inductor component shown in Figure 13, viewed from the direction of the coil axis.

[0156] As shown in Figure 14, the straight section 23 has a first straight section 23a on the top surface side and one or more second straight sections 23b on the mounting surface side with respect to the center line of the height T of the base body 10, and the first straight section 23a and the second straight section 23b are parallel to the mounting surface, and the curved section 24 has a first curved section 24a that connects the first straight section 23a and the second straight section 23b. As a result, the first straight section 23a and the second straight section 23b can be connected by the arc-shaped first curved section 24a, thereby reducing reflection loss at the connection point and increasing the Q value. Thus, when viewed from the coil axis direction, the coil 20 may have a track shape (elliptical shape).

[0157] Furthermore, in an inductor component 1E equipped with such a coil 20, as shown in Figure 13, at least one first curved portion 24a is provided with a notch 51 in a part in the coil axis direction, and it is preferable that the wiring thickness in the coil axis direction in the notch 51 is smaller than the wiring thickness in the coil axis direction in the straight portion 23. In a coil 20 with the shape shown in Figure 14, a large residual stress is generated in the first curved portion 24a connecting the first straight portion 23a and the second straight portion 23b, but by providing a notch 51 in this region as described above and reducing the wiring volume, the integral stress can be reduced, suppressing a decrease in impact resistance and preventing the occurrence of cracks in the product as a result.

[0158] More specifically, as shown in Figure 14, the multiple coil wirings 21 in the inductor component 1E have, for each turn of the coil 20, a straight section 23, which consists of a first straight section 23a located on the top side and a second straight section 23b located on the mounting side with respect to the center line of the height direction T of the base body 10, and a curved section 24, which consists of two first curved sections 24a connecting the first straight section 23a and the second straight section 23b. The first straight section 23a and the second straight section 23b are parallel to the bottom surface 12b, which is the mounting surface. Furthermore, a notch 51 is provided in a part of the first curved section 24a of each coil wiring 21 in the direction of the coil axis (see Figure 13).

[0159] Figure 15 is a schematic plan view showing another example (modification 1) of the inductor component shown in Figure 13, viewed from the coil axis direction.

[0160] As shown in Figure 15, the inductor component 1F has three second straight sections 23b, and the curved section 24 may further have two second curved sections 24b connecting the second straight sections 23b. In other words, the coil 20 may have a shape common to the coil 20 in the inductor component 1A shown in Figure 3 in the portion on the mounting surface. This allows the coil wiring 21 to be drawn largely inside the component, similar to the inductor component 1A, in that portion, increasing the cross-sectional area of ​​the coil 20 and improving the efficiency of obtaining the L value.

[0161] Furthermore, in the inductor component 1F equipped with such a coil 20, the notch 51 may be provided in a portion of the coil axis direction of at least one second curved portion 24b located on the mounting surface side, similar to the inductor component 1D. This reduces the integrated stress near the region where external shock is applied during the sorting process, similar to the inductor component 1D, thereby suppressing a decrease in the external shock resistance of that region.

[0162] [Embodiment 3] Figure 16 is a schematic plan view showing an example of an inductor component according to Embodiment 3 of the present invention.

[0163] As shown in Figure 16, when viewed from the coil axis direction, the multiple coil wirings 21 each have one arc portion 25 on the mounting surface side with respect to the center line in the height direction T of the base body 10, and the arc portion 25 is convex toward the mounting surface. The straight portion 23 has one first straight portion 23a on the top surface side with respect to the center line in the height direction T of the base body 10, and the first straight portion 23a is parallel to the mounting surface. The curved portion 24 is directly connected to the first straight portion 23a and has a first curved portion 24a that is electrically connected to the first straight portion 23a and the arc portion 25. This allows the distance between the mounting surface side portion of the coil wiring 21 and the first external electrode 30a and second external electrode 30b formed on the mounting surface side to be increased, reducing the high-frequency characteristics of the Q value due to stray capacitance, and thus increasing the Q value. Thus, when viewed from the coil axis direction, the coil 20 may have a heart shape because the multiple coil wirings 21 each have one arc portion 25 on the mounting surface side that is convex toward the mounting surface.

[0164] Furthermore, in an inductor component 1G equipped with such a coil 20, at least one first curved portion 24a is provided with a notch 51 in a part in the coil axis direction, and it is preferable that the wiring thickness in the coil axis direction in the notch 51 is smaller than the wiring thickness in the coil axis direction in the straight portion 23. By providing the notch 51 as described above, and reducing the wiring volume, especially in the curved portion 24 where residual stress after firing is large, the integral stress applied to any region can be reduced, thereby suppressing a decrease in impact resistance and preventing the occurrence of cracks in the product.

[0165] As shown in Figure 16, the inductor component 1G may have a straight section 23 that further includes a third straight section 23c connecting the first straight section 23a and the arc section 25, a first curved section 24a that connects the first straight section 23a and the third straight section 23c, and a curved section 24 that further includes a second curved section 24b connecting the arc section 25 and the third straight section 23c. In other words, the coil 20 may have a shape common to the coil 20 in the inductor component 1A shown in Figure 3, except for the portion having an arc section 25 that is convex on one mounting surface side. This allows the coil wiring 21 to be drawn largely inside the component in the other portion, similar to the inductor component 1A, increasing the cross-sectional area of ​​the coil 20 and improving the efficiency of obtaining the L value.

[0166] More specifically, as shown in Figure 16, the multiple coil wirings 21 in the inductor component 1G have, for each turn of the coil 20, one arc portion 25 on the mounting surface side with respect to the center line in the height direction T of the base body 10, and as straight portions 23, one first straight portion 23a located on the top surface side with respect to the center line in the height direction T of the base body 10, and two third straight portions 23c connecting the first straight portion 23a and the arc portion 25. As curved portions 24, there are two first curved portions 24a connecting the first straight portion 23a and the third straight portions 23c, and two second curved portions 24b connecting the third straight portions 23c and the arc portion 25. Furthermore, the first straight portion 23a is parallel to the bottom surface 12b, which is the mounting surface, and the arc portion 25 is convex toward the mounting surface. In addition, a notch 51 is provided in a part of the first curved portion 24a of each coil wiring 21 in the coil axis direction.

[0167] Furthermore, in the inductor component 1G equipped with such a coil 20, the notch 51 may be provided in a portion of the coil axis direction of at least one second curved portion 24b located on the mounting surface side, similar to the inductor component 1D. This reduces the integrated stress near the region where external shock is applied during the sorting process, similar to the inductor component 1D, thereby suppressing a decrease in the external shock resistance of that region.

[0168] Figure 17 is a schematic plan view showing another example (modification example 1) of the inductor component shown in Figure 16.

[0169] As shown in the inductor component 1H in Figure 17, the first curved portion 24a may directly connect the first straight portion 23a and the arc portion 25. That is, the coil 20 may have a shape common to the coil 20 in the inductor component 1E shown in Figure 14, except for the portion having an arc portion 25 that is convex on one mounting surface side. This allows the distance between the mounting surface side portion of the coil wiring 21 and the first external electrode 30a and second external electrode 30b formed on the mounting surface side to be further increased, and the high-frequency characteristics of the Q value due to stray capacitance are further reduced, thus allowing the Q value to be increased.

[0170] More specifically, as shown in Figure 17, each of the multiple coil wirings 21 in the inductor component 1H has, for each turn of the coil 20, one arc portion 25 on the mounting surface side with respect to the center line in the height direction T of the base body 10, one first straight portion 23a located on the top surface side with respect to the center line in the height direction T of the base body 10, and two first curved portions 24a connecting the first straight portion 23a and the arc portion 25. The first straight portion 23a is parallel to the bottom surface 12b, which is the mounting surface, and the arc portion 25 is convex toward the mounting surface. Furthermore, each first curved portion 24a of the coil wiring 21 is provided with a notch 51 in part in the coil axis direction.

[0171] Although Figures 16 and 17 show the case where the arc portion 25 has a virtual arc center within the product, the virtual arc center may also be located outside the product.

[0172] The arc portion 25 only needs to include one arc shape, and may further include straight lines extending tangentially from both ends of the arc shape, as shown in Figures 16 and 17.

[0173] [Common features of Embodiments 1-3] Figure 18 is a schematic perspective view showing another example of the inductor component shown in Figure 1.

[0174] As shown in Figure 18, the coil 20 in the inductor component 1I is composed of three layers of coil wiring 21a, 21b, and 21c.

[0175] In all of Embodiments 1 to 3, an example was shown in which the coil 20 is composed of 1.5T (turns), i.e., two layers of coil wiring 21, but it is not limited to 1.5T, and as shown in Figure 18, it may be composed of 2.5T or more, i.e., three or more layers of coil wiring 21. Furthermore, providing a notch 51 for coil wiring 21 with a large thickness in the coil axis direction has a greater effect in suppressing the decrease in resistance to external impacts.

[0176] The notches 51 may be provided in all layers of the coil 20, or in only some layers. Providing the notches 51 in all layers of the coil 20 increases the suppression effect against the decrease in external impact resistance, but at the same time, it reduces the suppression effect against the decrease in Q characteristics, so it is not necessarily preferable to provide the notches 51 in all layers of the coil 20.

[0177] In an inductor component in which the coil 20 is composed of three or more layers of coil wiring 21, if the notch 51 is provided in the coil wiring 21 located in the center of the base body 10 in the coil axis direction, it shall be provided in the middle of the curved portion 24 in the coil axis direction. However, for the purpose of reducing integral stress, the notch 51 does not necessarily have to be provided in the middle of the curved portion 24 in the coil axis direction, and may be provided closer to either side of the curved portion 24 in the coil axis direction.

[0178] Furthermore, when providing notches 51 in multiple curved sections 24, at least two configurations from the notch configurations of the inductor component 1A shown in Figure 1, the inductor component 1B shown in Figure 7, and the inductor component 1C shown in Figure 9 may be combined. In other words, notches may be provided in two or more locations among the notch placement locations (intermediate, outer end of the main body, and inner end of the main body) of the inductor components 1A to 1C.

[0179] Furthermore, in all of embodiments 1 to 3, an example has been shown in which one notch 51 is provided in the single layer of coil wiring 21 in the coil axis direction of the curved portion 24. However, a plurality of notches 51 may be provided in the single layer of coil wiring 21 in the coil axis direction of the curved portion 24.

[0180] The thickness of the notch 51 in the coil axis direction may be 1 / 10 or more and 1 / 2 or less of the thickness t2 of the straight section 23 in the coil axis direction. If multiple notches 51 are provided in the coil axis direction of the curved section 24, the thickness of the notch 51 in the coil axis direction shall be the sum of the thicknesses of each notch 51 in the coil axis direction.

[0181] Figure 19 is a schematic perspective view showing another example of the inductor component shown in Figure 7. Figure 20 is a schematic perspective view showing another example of the inductor component shown in Figure 7.

[0182] In the inductor components shown in Embodiments 1 to 3, the notch 51 penetrates the curved portion 24 in the width direction w1. This allows for a smaller volume of coil wiring 21 in the curved portion 24 compared to the case where the notch 51 does not penetrate the curved portion 24 in the width direction w1, thereby further reducing the integral stress.

[0183] On the other hand, as shown in Figures 19 and 20, in inductor components 1J and 1K, the notch 51 does not have to penetrate the curved portion 24 in the width direction w1. This prevents the cross-sectional area of ​​the coil wiring 21 in the curved portion 24 from becoming too small compared to the case where the notch 51 penetrates the curved portion 24 in the width direction w1, thereby further suppressing the deterioration of the Q characteristic.

[0184] As shown in Figure 19, the inductor component 1J may not penetrate the curved portion 24 in the width direction w1, and the notch 51 may be provided so that the inner circumference side of the curved portion 24 remains. This prevents the cross-sectional area of ​​the coil wiring 21 from becoming smaller on the inner circumference side of the curved portion 24 where current is generally concentrated, and further suppresses the decrease in Q characteristics.

[0185] As shown in Figure 20, the inductor component 1K may not penetrate the curved portion 24 in the width direction w1, and the notch 51 may be provided so that the outer circumference of the curved portion 24 remains.

[0186] Furthermore, in inductor components where the notch 51 does not penetrate the curved portion 24 in the width direction w1, the notch 51 may be provided at the outer end of the base body in the coil axis direction of the curved portion 24, as shown in Figures 19 and 20. This reduces the integrated stress in the region close to the surface of the base body 10, which is susceptible to external shocks, similar to inductor component 1B, thereby suppressing a decrease in external shock resistance and preventing the occurrence of cracks in the product.

[0187] As shown in Figures 19 and 20, when the notch 51 does not penetrate in the width direction w1, the wiring thickness in the coil axis direction of the notch 51 is the value obtained by subtracting the thickness of the notch 51 in the coil axis direction from the wiring thickness of the curved portion 24 in the coil axis direction. Therefore, in Figures 19 and 20 as well, the wiring thickness in the coil axis direction of the notch 51 is smaller than the wiring thickness in the coil axis direction of the straight portion.

[0188] In all of Embodiments 1 to 3, an example was shown in which the notch 51 is provided only in the curved portion 24, but the notch 51 may also be provided in the straight portion 23. Furthermore, the notch 51 may be provided only in the straight portion 23, or in both the straight portion 23 and the curved portion 24.

[0189] In all three embodiments, the mounting surface is shown to be parallel to the coil axis direction; however, the inductor component of the present invention may have a mounting surface perpendicular to the coil axis direction. [Explanation of symbols]

[0190] 1A, 1B, 1C, 1D, 1E, 1F, 1G, 1H, 1I, 1J, 1K Inductor Components 10 Base Body 11a, 11b End faces of the base body 12a Top surface of the base body 12b Bottom of the base body 13a, 13b Side view of the base body 15a, 15b, 15c, 15d, 15e, 15f, 15g, 15h, 15i Insulating layer 20 coils 21, 21a, 21b Coil wiring 22a 1st lead out wiring 22b 2nd lead out wiring 23 Straight section 23a 1st straight section 23b 2nd straight section 23c 3rd straight section 24 Curved section 24a First curved section 24b Second Curve Section 25 Arc section 29a Via conductor 30a 1st external electrode 30b 2nd external electrode 51 Notch 121aa, 121ab, 121ac, 121ba, 121bb, 121bc Coil conductor layer 122aa, 122ab, 122ac First Lead Conductor Layer 122ba, 122bb, 122bc Second lead conductor layer 129aa via conductor layer 130aa, 130ab, 130ac, 130ad, 130ae, 130af, 130ag First outer conductor layer 130ba, 130bb, 130bc, 130bd, 130be, 130bf, 130bg Second outer conductor layer CA coil shaft L (Length direction) T (height direction) W (width direction) t1 Thickness of each part of the curved section separated by the notch t2 Thickness of the coil wiring in the coil axis direction of the straight section w1 Width direction in coil wiring

Claims

1. The base body and, A coil provided inside the aforementioned body and wound spirally along the coil axis, The first external electrode and the second external electrode exposed on the surface of the aforementioned body, A first lead wire is provided inside the main body and electrically connects one end of the coil to the first external electrode, A second lead wire is provided inside the aforementioned body and electrically connects the other end of the coil to the second external electrode, Equipped with, The aforementioned element includes an insulator, The surface of the base body includes a mounting surface parallel to the coil axis direction and a top surface that is perpendicular to the coil axis direction and faces the mounting surface in the height direction, The first external electrode and the second external electrode are exposed so as to be separated from each other at least on the mounting surface of the base body. The coil includes a plurality of coil wirings, each of which is electrically connected. The plurality of coil wirings are electrically connected, with each coil wiring extending in a direction perpendicular to the coil axis and positioned at different locations in the coil axis. The plurality of coil wirings, when viewed from the direction of the coil axis, have straight sections and curved sections. At least one of the curved portions has a notch in part in the direction of the coil axis, An inductor component characterized in that the wiring thickness in the coil axis direction in the notched portion is smaller than the wiring thickness in the coil axis direction in the straight portion.

2. The inductor component according to claim 1, wherein the notch is provided in the middle of the curved portion in the coil axis direction.

3. The inductor component according to claim 1, wherein the notch is provided at the outer end of the curved portion in the coil axis direction.

4. The inductor component according to claim 1, wherein the notch is provided at the inner end of the curved portion in the coil axis direction.

5. When viewed from the direction of the coil axis, the coil has a polygonal shape. The straight section has, with respect to the center line in the height direction of the base body, a first straight section on the top surface side and one or more second straight sections on the mounting surface side, and further has a third straight section connecting the first straight section and the second straight sections. The first straight section and the second straight section are parallel to the mounting surface, The curved portion includes a first curved portion connecting the first straight portion and the third straight portion, and a second curved portion connecting either of the second straight portions and the third straight portion, or between the second straight portions. At least one of the first curved portion and the second curved portion is provided with the notch portion in a part of the coil axis direction, The inductor component according to any one of claims 1 to 4, wherein the wiring thickness in the coil axis direction in the notched portion is smaller than the wiring thickness in the coil axis direction in the straight portion.

6. The inductor component according to claim 5, wherein the notch is provided in at least one of the first curved portions.

7. The inductor component according to claim 5 or 6, wherein the notch is provided in at least one of the second curved portions.

8. The aforementioned straight section has, with respect to the center line in the height direction of the base body, one first straight section on the top surface side and one or more second straight sections on the mounting surface side. The first straight section and the second straight section are parallel to the mounting surface, The curved portion has a first curved portion connecting the first straight portion and the second straight portion. At least one of the first curved portions has the notch portion provided in a part of the coil axis direction, The inductor component according to any one of claims 1 to 4, wherein the wiring thickness in the coil axis direction in the notched portion is smaller than the wiring thickness in the coil axis direction in the straight portion.

9. When viewed from the direction of the coil axis, the plurality of coil wirings have one arc portion on the mounting surface side with respect to the center line in the height direction of the base body. The aforementioned arc portion is convex toward the mounting surface side, The aforementioned straight section has a first straight section on the top side with respect to the center line in the height direction of the base body, The first straight section is parallel to the mounting surface, The curved portion has a first curved portion that is directly connected to the first straight portion and electrically connected to the first straight portion and the arc portion. At least one of the first curved portions has the notch portion provided in a part of the coil axis direction, The inductor component according to any one of claims 1 to 4, wherein the wiring thickness in the coil axis direction in the notched portion is smaller than the wiring thickness in the coil axis direction in the straight portion.

10. The straight section further includes a third straight section connecting the first straight section and the arc section. The first curved section connects the first straight section and the third straight section, The inductor component according to claim 9, wherein the curved portion further comprises a second curved portion connecting the arc portion and the third straight portion.

11. The inductor component according to claim 9, wherein the first curved portion directly connects the first straight portion and the arc portion.

12. In the coil wiring described above, the direction perpendicular to the coil axis direction and the direction in which the coil wiring extends is defined as the width direction. The inductor component according to any one of claims 1 to 11, wherein the notch penetrates the curved portion in the width direction.

13. In the coil wiring described above, the direction perpendicular to the coil axis direction and the direction in which the coil wiring extends is defined as the width direction. The inductor component according to any one of claims 1 to 11, wherein the notch portion does not penetrate the curved portion in the width direction.

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