Inductor components

Abstract

The present invention provides an inductor component that can improve the inductance value. [Solution] The inductor component comprises a base body including a magnetic layer, A coil having an axis is placed inside the aforementioned body, The coil comprises an insulating layer that covers a portion of the outer surface of the coil, The coil has inductor wiring wound along a plane perpendicular to the axis, The inductor wiring has a first surface and a second surface that face each other in the axial direction, At least a portion of the first surface of the inductor wiring is in contact with the magnetic layer.

Description

Technical Field

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

Background Art

[0002] Conventionally, as an inductor component, there is one described in Japanese Unexamined Patent Application Publication No. 2021-174799 (Patent Document 1). The inductor component includes a body containing a magnetic layer and a coil disposed in the body and having an axis. The entire outer surface of the coil is covered with an insulating material.

Prior Art Documents

Patent Documents

[0003] [[ID=X]]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional inductor component, since the entire outer surface of the coil is covered with an insulating material, it is not possible to secure the volume of the magnetic layer, and there are cases where a desired inductance value cannot be obtained.

[0005] Therefore, an object of the present disclosure is to provide an inductor component capable of improving the inductance value.

Means for Solving the Problems

[0006] To solve the above problems, an inductor component according to an aspect of the present disclosure includes a body containing a magnetic layer, a coil disposed in the body and having an axis, and an insulating layer covering a part of the outer surface of the coil, where the coil has an inductor wiring wound along a plane orthogonal to the axis, The inductor wiring has a first surface and a second surface that face each other in the axial direction, At least a portion of the first surface of the inductor wiring is in contact with the magnetic layer.

[0007] According to the above embodiment, since at least a portion of the first surface of the inductor wiring is in contact with the magnetic layer, the volume of the magnetic layer can be increased compared to the case where the entire outer surface of the inductor wiring is covered with an insulating material. As a result, the inductance value of the inductor component can be improved. [Effects of the Invention]

[0008] According to an inductor component in one aspect of this disclosure, the inductance value can be improved. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic plan view showing a first embodiment of an inductor component. [Figure 2] This is a cross-sectional view taken along line II-II in Figure 1. [Figure 3] This is an enlarged view of section A in Figure 2. [Figure 4] This is a schematic cross-sectional view showing a modified example of an inductor component. [Figure 5A] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5B] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5C] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5D] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5E] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5F] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5G] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5H] This is an explanatory diagram illustrating the manufacturing process of inductor components. [Figure 5I] It is an explanatory diagram for explaining the manufacturing method of an inductor component. [Figure 5J] It is an explanatory diagram for explaining the manufacturing method of an inductor component. [Figure 6] It is a schematic cross-sectional view showing a second embodiment of an inductor component. [Figure 7] It is a schematic cross-sectional view showing a third embodiment of an inductor component. [Figure 8] It is a schematic plan view showing a fourth embodiment of an inductor component.

Mode for Carrying Out the Invention

[0010] Hereinafter, an inductor component, which is one aspect of the present disclosure, will be described in detail with reference to the illustrated embodiments. Note that the drawings include some schematic ones and may not reflect actual dimensions and ratios.

[0011] <First Embodiment> (Configuration) FIG. 1 is a schematic plan view showing a first embodiment of an inductor component. FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1. In FIG. 1, for convenience, the top surface portion of the coating insulation layer is shaded. In FIG. 2, for convenience, the seed layer is omitted. FIG. 2 corresponds to an example of the “cross-section orthogonal to the extending direction of the inductor wiring” described in the claims.

[0012] The inductor component 1 is mounted on an electronic device such as a personal computer, a DVD player, a digital camera, a TV, a mobile phone, or car electronics, and is, for example, a component having a rectangular parallelepiped shape as a whole. However, the shape of the inductor component 1 is not particularly limited and may be a cylindrical shape, a polygonal columnar shape, a frustum of a cone shape, or a frustum of a polygonal pyramid shape.

[0013] As shown in Figures 1 and 2, the inductor component 1 comprises a base body 10, a coil 15 disposed within the base body 10 and having an axis AX, a covering insulating layer 30 and an underlay insulating layer 70 covering a portion of the outer surface of the coil 15, a first external terminal 51 and a second external terminal 52 exposed on the first main surface 10a of the base body 10, and a coating film 60 provided on the first main surface 10a of the base body 10. The covering insulating layer 30 and the underlay insulating layer 70 correspond to examples of the "insulating layers" described in the claims.

[0014] The shape of the base body 10 is not particularly limited, but in this embodiment it is a rectangular parallelepiped. The outer surface of the base body 10 has a first main surface 10a and a second main surface 10b, and a first side surface 10c, a second side surface 10d, a third side surface 10e, and a fourth side surface 10f located between the first main surface 10a and the second main surface 10b and connecting the first main surface 10a and the second main surface 10b. The first main surface 10a and the second main surface 10b face each other. The first side surface 10c and the second side surface 10d face each other. The third side surface 10e and the fourth side surface 10f face each other.

[0015] In the figure, the thickness direction of the base body 10 is defined as the Z direction, the direction from the second main surface 10b toward the first main surface 10a is defined as the forward Z direction, and the direction opposite to the forward Z direction is defined as the reverse Z direction. In this specification, of the first main surface 10a and the second main surface 10b, the main surface side on which the external terminals 51 and 52 are provided is defined as the upper side. In this embodiment, the forward Z direction is the upper side. In a plane perpendicular to the Z direction of the base body 10, the length direction, which is the longitudinal direction of the base body 10 and the direction in which the first external terminal 51 and the second external terminal 52 are aligned, is defined as the X direction, and the width direction of the base body 10, which is perpendicular to the length direction, is defined as the Y direction. Furthermore, in the X direction, the direction from the first side surface 10c toward the second side surface 10d is defined as the forward X direction, and the direction opposite to the forward X direction is defined as the reverse X direction. In the Y direction, the direction from the third side surface 10e toward the fourth side surface 10f is defined as the forward Y direction, and the direction opposite to the forward Y direction is defined as the reverse Y direction. The forward Z direction corresponds to an example of the "first direction" described in the claims. The reverse Z direction corresponds to an example of the "second direction" described in the claims.

[0016] The element 10 includes a first magnetic layer 11 and a second magnetic layer 12 arranged sequentially along the forward Z direction. This "sequentially" simply indicates the positional relationship between the first magnetic layer 11 and the second magnetic layer 12, and is unrelated to the order in which the first magnetic layer 11 and the second magnetic layer 12 were formed. The first magnetic layer 11 and the second magnetic layer 12 correspond to an example of the "magnetic layer" described in the claims.

[0017] The first magnetic layer 11 and the second magnetic layer 12 each contain magnetic powder and a resin containing the magnetic powder. The resin is, for example, an organic insulating material such as epoxy, a mixture of epoxy and acrylic, or a mixture of epoxy, acrylic, and other materials. The magnetic powder is, for example, an FeSi-based alloy such as FeSiCr, an FeCo-based alloy, an Fe-based alloy such as NiFe, or an amorphous alloy thereof. The magnetic powder may also be ferrite. The average particle size of the magnetic powder is preferably 5 μm or less. The first magnetic layer 11 and the second magnetic layer 12 may not contain organic resin, such as a sintered body of ferrite or magnetic powder.

[0018] The coil 15 includes an inductor wiring 150 and first lead wiring 21 and second lead wiring 22 provided inside the base body 10 such that their end faces are exposed from the first main surface 10a of the base body 10. Inductor wiring refers to wiring wound spirally on a plane including the inner circumference 151 and the outer circumference 152. The coil is a component that includes, in addition to the inductor wiring, wiring (in this embodiment, the first and second lead wirings 21 and 22) that extract the signal from the inductor wiring to the outside of the base body 10. The inductor wiring 150 is wound between the first magnetic layer 11 and the second magnetic layer 12 along a plane (XY plane) perpendicular to the axis AX of the coil 15. Specifically, the first magnetic layer 11 is located in the opposite Z direction to the inductor wiring 150, and the second magnetic layer 12 is located in the forward Z direction to the inductor wiring 150, and in a direction perpendicular to the forward Z direction.

[0019] The inductor wiring 150 is wound in a spiral shape clockwise from the outer circumference 152 to the inner circumference 151 when viewed from the Z direction. Preferably, the number of turns of the inductor wiring 150 is 1 turn or more. This can improve the inductance value. 1 turn or more means that in a cross section perpendicular to the axis of the inductor wiring, the inductor wiring has portions that run parallel in the winding direction adjacent to each other in the radial direction when viewed from the axial direction, while less than 1 turn means that in a cross section perpendicular to the axis, the inductor wiring does not have portions that run parallel in the winding direction adjacent to each other in the winding direction when viewed from the axial direction. In this embodiment, the number of turns of the inductor wiring 150 is 2.5 turns.

[0020] The inductor wiring 150 has a top surface 150a and a bottom surface 150b facing the axial direction AX of the coil 15. Specifically, the inductor wiring 150 has a top surface 150a facing the forward Z direction (i.e., upward) and a bottom surface 150b facing the reverse Z direction. In this specification, the top surface 150a of the inductor wiring 150 does not include the connection portion with the first and second lead wirings 21 and 22. The top surface 150a corresponds to an example of the "first surface" described in the claims. The bottom surface 150b corresponds to an example of the "second surface" described in the claims. The inductor wiring 150 has two side surfaces 150c and 150d connecting the top surface 150a and the bottom surface 150b. Specifically, the inductor wiring 150 has a first side surface 150c facing radially outward and a second side surface 150d facing radially inward.

[0021] The outer circumference end 152 of the inductor wiring 150 is connected to the first external terminal 51 via a first lead wire 21 that is in contact with the top surface of the outer circumference end 152. The inner circumference end 151 of the inductor wiring 150 is connected to the second external terminal 52 via a second lead wire 22 that is in contact with the top surface of the inner circumference end 151. With this configuration, the inductor wiring 150 is electrically connected to the first external terminal 51 and the second external terminal 52.

[0022] The inductor wiring 150 is preferably made of Au, Pt, Pd, Ag, Cu, Al, Co, Cr, Zn, Ni, Ti, W, Fe, Sn, In, or compounds thereof. The inductor wiring 150 is formed, for example, by electroplating. The inductor wiring 150 may also be formed by electroless plating, sputtering, vapor deposition, coating, or the like.

[0023] The first lead wire 21 extends in the forward Z direction from the top surface of the outer peripheral end 152 of the inductor wire 150 and penetrates the interior of the covering insulating layer 30 and the second magnetic layer 12. The first lead wire 21 is preferably made of Cu, Ag, Au, Fe, or a compound thereof. The first lead wire 21 includes a first via wire 212 provided on the top surface of the outer peripheral end 152 of the inductor wire 150 and penetrating the interior of the covering insulating layer 30, and a first columnar wire 211 extending in the forward Z direction from the top surface of the first via wire 212, penetrating the interior of the second magnetic layer 12, with its end face exposed to the first main surface 10a of the base body 10. The via wire is a conductor with a smaller line width (diameter, cross-sectional area) than the columnar wire.

[0024] The second lead wiring 22 extends in the forward Z direction from the top surface of the inner circumference end 151 of the inductor wiring 150 and penetrates the interior of the covering insulating layer 30 and the second magnetic layer 12. The second lead wiring 22 is preferably made of Cu, Ag, Au, Fe, or a compound thereof. The second lead wiring 22 includes a second via wiring 222 provided on the top surface of the inner circumference end 151 of the inductor wiring 150 and penetrating the interior of the covering insulating layer 30, and a second columnar wiring 221 extending in the forward Z direction from the top surface of the second via wiring 222, penetrating the interior of the second magnetic layer 12, with its end face exposed to the first main surface 10a of the base body 10. The first and second lead wirings 21 and 22 are preferably made of the same material as the inductor wiring 150.

[0025] The first and second external terminals 51 and 52 are provided on the first main surface 10a of the base body 10. The first and second external terminals 41 and 42 are made of conductive material and have a three-layer structure in which Cu, which has low electrical resistance and excellent stress resistance, Ni, which has excellent corrosion resistance, and Au, which has excellent solder wettability and reliability, are arranged in this order from the inside to the outside.

[0026] The first external terminal 51 contacts the end face of the base body 10 of the first lead wire 21 that is exposed from the first main surface 10a, and is electrically connected to the first lead wire 21. As a result, the first external terminal 51 is electrically connected to the outer circumference end 152 of the inductor wire 150. The second external terminal 52 contacts the end face of the base body 10 of the second lead wire 22 that is exposed from the first main surface 10a, and is electrically connected to the second lead wire 22. As a result, the second external terminal 52 is electrically connected to the inner circumference end 151 of the inductor wire 150. In Figure 1, the first and second external terminals 51 and 52 are shown by dashed lines for convenience.

[0027] The coating insulating layer 30 and the underlay insulating layer 70 are made of insulating materials that do not contain magnetic materials. The insulating material is preferably made of epoxy, acrylic, phenol, polyimide, or a mixture thereof.

[0028] Figure 3 is an enlarged view of section A in Figure 2. As shown in Figure 3, at least a portion of the top surface 150a of the inductor wiring 150 is in contact with at least one of the first magnetic layer 11 and the second magnetic layer 12. In this embodiment, only a portion of the top surface 150a of the inductor wiring 150 is in contact with the second magnetic layer 12.

[0029] Specifically, the base insulating layer 70 is laminated on the first magnetic layer 11 so as to cover the entire upper surface of the first magnetic layer 11. The inductor wiring 150 is laminated on the base insulating layer 70. The entire bottom surface 150b of the inductor wiring 150 is in contact with the upper surface of the base insulating layer 70.

[0030] The insulating coating layer 30 is provided on the base insulating layer 70 and covers a portion of the outer surface of the inductor wiring 150. The insulating coating layer 30 has a top surface portion 31 and a wall portion 32.

[0031] The wall portion 32 is provided on at least one of the first side surface 150c and the second side surface 150d of the inductor wiring 150. In this embodiment, the wall portion 32 is provided on both the first side surface 150c and the second side surface 150d. The wall portion 32 extends in the Z direction in a cross section perpendicular to the extending direction of the inductor wiring 150 (i.e., the cross section shown in Figure 2). The wall portion 32 is in contact with the entire surface of the first side surface 150c and the entire surface of the second side surface 150d. The lower surface of the wall portion 32 is in contact with the upper surface of the underlying insulating layer 70. In short, the wall portion 32 is provided on the innermost inner surface 150d1 of the inductor wiring 150, the outermost outer surface 150c1 of the inductor wiring 150, and between the turns of the inductor wiring 150.

[0032] The innermost circumference of an inductor wiring refers to the inner circumference in the radial direction if the inductor wiring has less than one turn, and the inner circumference in the radial direction of the portion of the inductor wiring that constitutes one turn, including the inner circumference end, if the inductor wiring has one or more turns. The outermost circumference of an inductor wiring refers to the outer circumference in the radial direction if the inductor wiring has less than one turn, and the outer circumference in the radial direction of the portion of the inductor wiring that constitutes one turn, including the outer circumference end, if the inductor wiring has one or more turns.

[0033] The top surface portion 31 is provided on a part of the top surface 150a of the inductor wiring 150. Specifically, the top surface portion 31 is provided in a predetermined area around the first lead wiring 21 on the top surface 150a of the inductor wiring 150, as viewed from the Z direction. The predetermined area is an area in which insulation between the top surface 150a of the inductor wiring and the first lead wiring 21 can be ensured. In this embodiment, the shape of the predetermined area is such that, as viewed from the Z direction, it follows the outer shape (rectangle) of the first lead wiring 21. This makes it easy to ensure insulation between the top surface 150a of the inductor wiring and the first lead wiring 21.

[0034] Similarly, the top surface portion 31 is provided in a predetermined area around the second lead wiring 22 on the top surface 150a of the inductor wiring 150, as viewed from the Z direction. The predetermined area is the area in which insulation between the top surface 150a of the inductor wiring and the second lead wiring 22 can be ensured. In this embodiment, the shape of the predetermined area is such that, as viewed from the Z direction, it follows the outer shape (circular) of the second lead wiring 22. This makes it easy to ensure insulation between the top surface 150a of the inductor wiring and the second lead wiring 22.

[0035] Of the top surface 150a of the inductor wiring 150, the portion where the top surface portion 31 of the insulating coating layer 30 is not provided is in contact with the second magnetic layer 12. With this configuration, of the top surface 150a of the inductor wiring 150, only the portion where the top surface portion 31 of the insulating coating layer 30 is not provided is in contact with the second magnetic layer 12.

[0036] In the inductor component 1, at least a portion of the top surface 150a of the inductor wiring 150 is in contact with either the first magnetic layer 11 or the second magnetic layer 12. Therefore, compared to the case where the entire outer surface of the inductor wiring 150 is covered with insulating material, the volume of the first magnetic layer 11 and the second magnetic layer 12 can be increased. As a result, the inductance value of the inductor component 1 can be improved.

[0037] In particular, in inductor components where the area of ​​the top surface 150a and the bottom surface 150b of the inductor wiring 150 are each larger than the area of ​​the inner surface 150d1 of the innermost circumference of the inductor wiring 150, the above effect of increasing the volume of the first magnetic layer 11 and the second magnetic layer 12 is greater than when only the inner surface 150d1 of the outer surface of the inductor wiring 150 is in contact with the second magnetic layer 12.

[0038] Preferably, as shown in Figure 3, in a cross-section perpendicular to the extending direction of the inductor wiring 150, the inductor wiring 150 has two sides 150c and 150d connecting the top surface 150a and the bottom surface 150b, and the insulating coating layer 30 has a wall portion 32 provided on at least one of the two sides 150c and 150d. Specifically, the insulating coating layer 30 has a first wall portion 321 provided on the first side 150c and a second wall portion 322 provided on the second side 150d. With this configuration, the inductor can suppress short circuits between the two sides 150c and 150d of the wiring 150 and other conductive members.

[0039] Preferably, when the first direction D1 is defined as the axial direction AX, from the bottom surface 150b of the inductor wiring 150 toward the top surface 150a, the end face of the wall portion 32 in the first direction D1 is located on the side of the top surface 150a of the inductor wiring 150 that is located on the side of the first direction D1. Specifically, the first end face 321a of the first wall portion 321 in the first direction D1 is located on the side of the first direction D1 that is located on the side of the top surface 150a of the inductor wiring 150. The second end face 322a of the second wall portion 322 in the first direction D1 is located on the side of the first direction D1 that is located on the side of the top surface 150a of the inductor wiring 150. With this configuration, the inductor can more reliably suppress short circuits between the two sides 150c, 150d of the wiring 150 and other conductive members.

[0040] Preferably, the distance in the first direction D1 between the top surface 150a of the inductor wiring 150 and the end face of the wall portion 32 in the first direction D1 is 5 μm or more and 20 μm or less. Specifically, the distance h1 in the first direction D1 between the top surface 150a of the inductor wiring 150 and the first end face 321a of the first wall portion 321 is 5 μm or more and 20 μm or less. The distance h2 in the first direction D1 between the top surface 150a of the inductor wiring 150 and the second end face 322a of the second wall portion 322 is 5 μm or more and 20 μm or less.

[0041] According to the above configuration, since distances h1 and h2 are 5 μm or more, it is possible to suppress short circuits between the innermost inner surface 150d1 of the inductor wiring 150 via the second magnetic layer 12. Also, as in this embodiment, if the inductor wiring 150 has one or more turns, it is possible to suppress short circuits between adjacent turns. Since distances h1 and h2 are 20 μm or less, the inductor wiring 150 can be formed into a desired shape. As a result, a desired inductor value can be obtained. If distances h1 and h2 exceed 20 μm, after the wall portion 32 is formed, the wall portion 32 may tilt in the forward X direction or the reverse X direction, making it impossible to form the inductor wiring 150 into a desired shape. Also, since distances h1 and h2 are 20 μm or less, the volume of the second magnetic layer 12 can be further increased.

[0042] As in this embodiment, when there are multiple wall portions 32 in the X direction in a cross section perpendicular to the extending direction of the inductor wiring 150, it is most preferable that the above distance is 5 μm or more and 20 μm or less in all wall portions 32. However, it is not limited to this, and in a cross section perpendicular to the extending direction of the inductor wiring 150, the above distance may be 5 μm or more and 20 μm or less in some of the wall portions 32 among the multiple wall portions 32.

[0043] Preferably, as shown in Figures 1 and 2, the insulating coating layer 30 is provided on at least a portion of the top surface 150a of the inductor wiring 150. This configuration allows for an increase in the volume of the second magnetic layer 12 while ensuring insulation between the top surface 150a and other conductive members.

[0044] Preferably, as shown in Figures 1 and 2, when the first direction D1 is the direction in the axial AX direction from the bottom surface 150b of the inductor wiring 150 toward the top surface 150a, the inductor wiring 150 further comprises first and second lead wires 21 and 22 that are connected to the top surface 150a at the extending ends of the inductor wiring 150 (i.e., the inner circumference end 151 and the outer circumference end 152), extend in the first direction D1, and are exposed from the outer surface of the base body 10, and the covering insulating layer 30 (i.e., top surface portion 31) provided on a part of the top surface 150a of the inductor wiring 150 is provided over a range of 80 μm or more from the periphery of the first and second lead wires 21 and 22 on the top surface 150a.

[0045] According to the above configuration, the occurrence of a short circuit between the portion of the top surface 150a of the inductor wiring 150 that is in contact with the second magnetic layer 12 and the first and second lead wirings 21 and 22 can be suppressed. Specifically, when a potential difference is generated in the conductor portion of the inductor component 1 due to ESD (Electrostatic Discharge), a short circuit may occur via the magnetic powder of the second magnetic layer 12. In particular, the distance between the first and second lead wirings 21 and 22 and the inductor wiring 150 surrounding the first and second lead wirings 21 and 22 is relatively short, making it prone to short circuits. The inventors have found that even if a portion of the top surface 150a of the inductor wiring 150 is not covered by the insulating coating layer 30 and is in contact with the second magnetic layer 12, the risk of short-circuiting can be reduced to the same extent as when the entire top surface 150a of the inductor wiring 150 is covered by the insulating coating layer 30 by providing the top surface portion 31 of the insulating coating layer 30 over a range of 80 μm or more from the periphery of the first and second lead-out wirings 21 and 22.

[0046] (modified version) Figure 4 is a schematic cross-sectional view showing an inductor component 1A according to a modified example. Figure 4 corresponds to Figure 3.

[0047] As shown in Figure 4, in a cross-section perpendicular to the extending direction of the inductor wiring 150, the inductor wiring 150 has two side surfaces 150c and 150d connecting the top surface 150a and the bottom surface 150b. The two side surfaces 150c and 150d of the inductor wiring located at the innermost circumference include an inner circumference surface 150d1 and an outer circumference surface 150c2 facing the inner circumference surface 150d1. The insulating coating layer 30 has at least a first wall portion 321 and a second wall portion 322 provided on the inner circumference surface 150d1 and the outer circumference surface 150c2. The end face 322a of the second wall portion 322 provided on the inner circumference surface 150d1 in the first direction D1 is located on the second direction D2 side, which is opposite to the first direction D1, than the end face 321a of the first wall portion 321 provided on the outer circumference surface 150c2 in the first direction D1.

[0048] Here, if the number of turns of the inductor wiring 150 is less than one turn, the above-mentioned "both sides of the inductor wiring located at the innermost circumference" refers to both sides of the inductor wiring 150 in a cross-section perpendicular to the direction of extension of the inductor wiring 150. If the number of turns of the inductor wiring 150 is one turn or more, the above-mentioned "both sides of the inductor wiring located at the innermost circumference" refers to both sides of the cross-section of the inductor wiring that includes the innermost circumference, among the cross-sections of multiple inductor wirings that appear in a cross-section perpendicular to the direction of extension of the inductor wiring 150.

[0049] According to the above configuration, it is possible to suppress the obstruction of the magnetic flux by the second wall portion 322 of the insulating coating layer 30 in the portion where the magnetic flux wraps around.

[0050] Preferably, as shown in Figure 4, the end face 322a of the second wall portion 322 provided on the inner circumferential surface 150d1 in the first direction D1 is located on the same plane as the top surface 150a of the inductor wiring 150.

[0051] According to the above configuration, the obstruction of the magnetic flux by the second wall portion 322 of the insulating coating layer 30 in the portion where the magnetic flux wraps around can be further suppressed.

[0052] (Manufacturing method) Next, the manufacturing method of the inductor component 1 will be described with reference to Figures 5A to 5J. Figures 5A to 5J correspond to the II-II cross-section (Figure 2) of Figure 1. For convenience, the description of the second lead wiring side is omitted in Figures 5A to 5J.

[0053] As shown in Figure 5A, a base insulating layer 70 that does not contain magnetic material is formed on the substrate 90. The substrate 90 is made of, for example, sintered ferrite and is in the shape of a flat plate.

[0054] The base insulating layer 70 is made of, for example, a polyimide resin that does not contain magnetic material. The base insulating layer 70 is formed by coating the substrate 90 with the polyimide resin by printing, coating, or the like. After coating, the base insulating layer 70 may be modified by patterning using photolithography to leave only the polyimide resin in the area where the inductor wiring 150 will be formed. Before forming the base insulating layer 70, an insulating material that will serve as a grinding protection layer may be formed on the substrate 90.

[0055] As shown in Figure 5B, a seed layer 81 is formed on the underlying insulating layer 70. Specifically, the material for the seed layer 81 (for example, a titanium / copper alloy) is deposited on the upper surface of the underlying insulating layer 70 by sputtering, and the seed layer 81 is formed by patterning using photolithography.

[0056] As shown in Figure 5C, a wall portion 32, which will become part of the covering insulating layer, is formed on the underlying insulating layer 70. The wall portion 32 is formed, for example, from a photosensitive permanent photoresist. A photosensitive permanent photoresist is a photoresist that is not removed after processing. Specifically, a photosensitive permanent photoresist is laminated onto the underlying insulating layer 70, exposed to light, and developed. As a result, the material in the unexposed parts is removed, and the wall portion 32 is formed.

[0057] As shown in Figure 5D, electroplating is performed while supplying power to the seed layer 81. This forms inductor wiring 150 between the wall portions 32.

[0058] As shown in Figure 5E, the top surface portion 31 of the insulating coating layer 30 is formed on a part of the top surface 150a of the inductor wiring 150. Specifically, a dry film resist (DFR) is laminated onto the top surface 150a of the inductor wiring 150, and then exposed and developed. This removes the material from the unexposed parts, forming the top surface portion 31. At this time, the dry film resist located in the area where the top surface 150a of the inductor wiring 150 and the second magnetic layer 12 come into contact is removed. As a result, when the second magnetic layer 12 is pressed in a later process, a part of the top surface 150a of the inductor wiring 150 comes into contact with the second magnetic layer.

[0059] As shown in Figure 5F, a seed layer 82 is formed by sputtering so as to cover the exposed portion of the top surface 150a of the inductor wiring 150 and the top surface 31 and wall portion 32 of the insulating coating layer 30. At this time, by ensuring that the distance between the end face of the wall portion 32 of the insulating coating layer 30 and the top surface 150a of the inductor wiring 150 is 20 μm or less, the sputtered film can be well attached even to the stepped portion between the upper end face of the wall portion 32 and the top surface 150a, and the seed layer 82 can be well formed.

[0060] As shown in Figure 5G, a first via wiring 212 and a first columnar wiring 211 are formed on the outer peripheral end 152 of the inductor wiring 150. Specifically, a resist film 320 is formed on the seed layer 82, and an opening is provided in the resist film 320 at a position corresponding to the first via wiring 212. At this time, the distance between the end face of the wall portion 32 of the covering insulating layer 30 and the top surface 150a of the inductor wiring 150 is 20 μm or less, so that the resist film 320 can be made into a desired shape. This also allows the first via wiring 212 and the first columnar wiring 211 to be made into a desired shape. Subsequently, electroplating is performed while supplying power to the seed layer 82 to form a plating layer in the opening. This forms the first via wiring 212 and the first columnar wiring 211 in the opening.

[0061] As shown in Figure 5H, the resist film 320 is peeled off, the exposed seed layer 82 is removed, and the second magnetic layer 12 is pressed onto the substrate 90 from above toward the inductor wiring 150. This covers the inductor wiring 150, the underlying insulating layer 70, the covering insulating layer 30, and the first columnar wiring 211 with the second magnetic layer 12.

[0062] As shown in Figure 5I, the upper surface of the second magnetic layer 12 is ground to expose the upper surface of the first columnar wiring 211.

[0063] As shown in Figure 5J, a coating film 60 is formed on the upper surface of the second magnetic layer 12. The coating film 60 is formed, for example, by solder resist. Then, the substrate 90 is ground to expose the lower surface of the underlying insulating layer 70. Next, the first magnetic layer 11 is pressed from below the underlying insulating layer 70 toward the inductor wiring 150. This covers the lower surface of the underlying insulating layer 70 with the first magnetic layer 11. Then, the lower surface of the first magnetic layer 11 is ground to adjust its thickness. Next, the first external terminal 51 is formed so as to cover the upper surface of the first columnar wiring 211. The first external terminal 51 is a three-layer structure of Cu / Ni / Au formed, for example, by electroless plating. Then, the inductor component 1 is manufactured by dicing it into individual pieces using a dicer or the like.

[0064] <Second Embodiment> Figure 6 is a schematic cross-sectional view showing a second embodiment of the inductor component. Figure 6 corresponds to the II-II cross-sectional view in Figure 1. For convenience, the description of the second lead-out wiring side is omitted in Figure 6. The second embodiment differs from the first embodiment in that the top surface of the covering insulation layer and the underlay insulation layer are not provided. This difference in configuration will be described below. Other configurations are the same as in the first embodiment, and the same reference numerals are used as in the first embodiment, so their descriptions are omitted.

[0065] As shown in Figure 6, the insulating coating layer 30B has only a wall portion 32 and no top portion. As a result, the entire top surface 150a of the inductor wiring 150 is in contact with the second magnetic layer 12. The first lead wiring 21B does not have via wiring, and the first columnar wiring 211 is directly connected to the inductor wiring 150. With this configuration, the volume of the second magnetic layer 12 can be further increased, and thus the inductance value of the inductor component 1B can be further improved.

[0066] In the inductor component 1B, no underlying insulating layer is provided, and the upper surface of the first magnetic layer 11 and the lower surface of the second magnetic layer 12 are in contact. As a result, the entire bottom surface 150b of the inductor wiring 150 is in contact with the first magnetic layer 11. With this configuration, the thickness of the first magnetic layer 11 in the Z direction can be increased compared to the case where an underlying insulating layer is provided, so the volume of the first magnetic layer 11 can be further increased, and the inductance value of the inductor component 1B can be further improved.

[0067] The inductor component 1B can be manufactured, for example, by not providing the top surface portion 31 in the process shown in Figure 5E, and by removing the underlying insulating layer 70 after grinding the substrate 90 in the process shown in Figure 5J.

[0068] <Third Embodiment> Figure 7 is a schematic cross-sectional view showing a third embodiment of the inductor component. Figure 7 corresponds to Figure 3. The third embodiment differs from the first embodiment in that the innermost surface of the innermost circumference of the inductor wiring does not have a wall portion of the insulating layer. This differing configuration will be described below. Other configurations are the same as those of the first embodiment, and are denoted by the same reference numerals as in the first embodiment, and their descriptions will be omitted.

[0069] As shown in Figure 7, at least a portion of the innermost inner surface 150d1 of the inductor wiring 150 is in contact with the second magnetic layer 12. In this embodiment, the entire inner surface 150d1 of the innermost inner surface 150d1 of the inductor wiring 150 is in contact with the second magnetic layer 12. With this configuration, the volume of the second magnetic layer 12 can be further increased, and thus the inductance value of the inductor component 1C can be further improved.

[0070] The inductor component 1C can be manufactured, for example, by not providing the wall portion 32 corresponding to the position of the innermost inner surface of the inductor wiring in the process shown in Figure 5C.

[0071] <Fourth Embodiment> Figure 8 is a schematic plan view showing a fourth embodiment of the inductor component. Figure 8 corresponds to Figure 1. The fourth embodiment differs from the first embodiment mainly in the position where the top surface of the insulating coating layer is provided. This differing configuration is described below. Other configurations are the same as those of the first embodiment, and are given the same reference numerals as in the first embodiment, and their descriptions are omitted. In Figure 8, for convenience, the location where the top surface of the insulating coating layer is present is indicated by diagonal lines.

[0072] As shown in Figure 8, when the axial direction AX is defined as the direction from the bottom surface to the top surface of the inductor wiring 150, the inductor wiring 150 further comprises first and second lead wires 21 and 22 that are connected to the top surface at the extending ends (i.e., the inner circumference end 151 and the outer circumference end 152) of the inductor wiring 150, extend in the first direction, and are exposed from the outer surface of the base body 10. The insulating covering layer 30 (i.e., the top surface portion 31) provided on a part of the top surface of the inductor wiring 150 is separated from the first and second lead wires 21 and 22.

[0073] Specifically, the top surface portion 31 of the insulating coating layer 30 is provided on the entire top surface of the inductor wiring 150, excluding the area surrounding the first and second lead wirings 21 and 22. However, the top surface portion 31 of the insulating coating layer 30 may be provided on only a portion of the area excluding the area surrounding the first and second lead wirings 21 and 22, as long as it is separated from the first and second lead wirings 21 and 22. In this embodiment, since the top surface portion 31 of the insulating coating layer 30 is not provided in the area surrounding the first and second lead wirings 21 and 22, unlike the first embodiment, the first and second lead wirings 21 and 22 do not have first and second via wirings 212 and 222. That is, the bottom surfaces of the first and second columnar wirings 211 and 221 of the first and second lead wirings 21 and 22 are in direct contact with the top surface of the inductor wiring 150.

[0074] According to the above configuration, the top surface portion 31 can be provided at a desired location between the inductor wirings 150 where short circuits are likely to occur. Furthermore, since the first and second lead wirings 21 and 22 do not have first and second via wirings 212 and 222 as shown in Figure 1, the contact area between the first and second lead wirings 21 and 22 (i.e., the first and second columnar wirings 211 and 221) and the inductor wiring 150 can be increased, the fixing strength between the first and second lead wirings 21 and 22 and the inductor wiring 150 is increased, and problems such as disconnection due to external stress can be suppressed.

[0075] This disclosure is not limited to the embodiments described above, and design modifications are possible without departing from the gist of this disclosure. For example, the features of each of the first to fourth embodiments may be combined in various ways.

[0076] In the above embodiment, first and second lead-out wiring, first and second external terminals, and a protective film were provided, but these components are not essential and may be omitted or replaced with other components.

[0077] In the above embodiment, the inductor wiring was one layer, but it may be two or more layers. In this case, "top surface of the inductor wiring" refers to the top surface of the uppermost inductor wiring, and "bottom surface of the inductor wiring" refers to the bottom surface of the lowest inductor wiring.

[0078] In the above embodiment, at least a portion of the top surface of the inductor wiring was in contact with the second magnetic layer. However, the entire top surface of the inductor wiring may be covered with a insulating coating layer, and at least a portion of the bottom surface of the inductor wiring may be in contact with the first magnetic layer. In this case, the top surface of the inductor wiring corresponds to an example of the "second surface" described in the claims, and the bottom surface of the inductor wiring corresponds to an example of the "first surface" described in the claims.

[0079] In the above embodiment, a wall portion of the insulating coating layer was present in the entire region between adjacent turns of the inductor wiring, but a second magnetic layer may be present between adjacent turns. Specifically, in a cross-section perpendicular to the extending direction of the inductor wiring, a wall portion of the insulating coating layer may be provided on at least one of the two sides of the inductor wiring, and a second magnetic layer may be present between adjacent turns.

[0080] (Examples) Chips were fabricated with distances h between the top surface of the inductor wiring and the first-direction end face of the wall portion of the insulating layer, varying to 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, and 10 μm. A humidity resistance load test was then performed on each chip. In the humidity resistance load test, current was passed through the chip in a high-temperature, high-humidity environment, and the insulation resistance of the inductor wiring was measured after a predetermined time. The conditions for the humidity resistance load test were 85°C, 85% RH, 1 A, and 500 hr. The number of chips with normal insulation resistance (number of good chips) out of 15 chips was investigated. The test results are shown in Table 1.

[0081] [Table 1]

[0082] Chips were fabricated with varying distances h between the top surface of the inductor wiring and the first-direction end face of the wall portion of the insulating coating layer, at 10 μm, 15 μm, 20 μm, 25 μm, and 30 μm. The presence or absence of manufacturing process defects was investigated. Specifically, for samples in which a seed layer was formed by sputtering after the wall portion of the insulating coating layer was formed, the deposition state of the seed layer was observed using an optical microscope. Similarly, for samples in which a resist film was formed after the seed layer was formed, the deposition state of the resist film was observed using an optical microscope. The number of chips with normal seed layer and resist film deposition (number of good chips) out of 15 chips was then investigated. The investigation results are shown in Table 2.

[0083] [Table 2]

[0084] As shown in Table 1, some chips exhibited abnormal insulation resistance when the distance h was 4 μm or less. As shown in Table 2, some chips experienced manufacturing process defects when the distance h was 25 μm or more.

[0085] This disclosure includes the following aspects: <1> A base body containing a magnetic layer, A coil having an axis is placed inside the aforementioned body, The coil comprises an insulating layer that covers a portion of the outer surface of the coil, The coil has inductor wiring wound along a plane perpendicular to the axis, The inductor wiring has a first surface and a second surface that face each other in the axial direction, An inductor component in which at least a portion of the first surface of the inductor wiring is in contact with the magnetic layer. <2> The entire surface of the first surface of the inductor wiring is in contact with the magnetic layer. <1> The inductor components listed below. <3> The entire surface of the second surface of the inductor wiring is in contact with the magnetic layer. <1> or <2> The inductor components listed below. <4> In a cross-section perpendicular to the direction of extension of the inductor wiring, The inductor wiring has two sides that connect the first surface and the second surface, The insulating layer has a wall portion provided on at least one of the two sides, <1> from <3> An inductor component listed in any one of the following. <5> When the axial direction toward the first surface of the inductor wiring is defined as the first direction, the end face of the wall portion in the first direction is located on the side of the first surface of the inductor wiring that is located on the first direction side. <4> The inductor components listed below. <6> The distance in the first direction between the first surface of the inductor wiring and the end surface of the wall portion in the first direction is 5 μm or more and 20 μm or less. <5> The inductor components listed below. <7> At least a portion of the inner surface of the innermost circumference of the inductor wiring is in contact with the magnetic layer. <1> from <6> An inductor component listed in any one of the following. <8> In a cross-section perpendicular to the direction of extension of the inductor wiring, The inductor wiring has two sides that connect the first surface and the second surface, The two sides of the inductor wiring located at the innermost circumference include the inner circumference surface of the innermost circumference and the outer circumference surface facing the inner circumference surface, The insulating layer has at least wall portions provided on each of the inner and outer surfaces, When the axial direction of the inductor wiring, specifically the direction from the second surface toward the first surface, is defined as the first direction, the end face of the wall portion provided on the inner circumferential surface in the first direction is located on the second direction side, opposite to the first direction, than the end face of the wall portion provided on the outer circumferential surface in the first direction. <1> from <6> An inductor component listed in any one of the following. <9> The end face in the first direction of the wall portion provided on the inner circumferential surface is located on the same plane as the first surface of the inductor wiring. <8> The inductor components listed below. <10> The insulating layer is provided at least on a portion of the first surface of the inductor wiring. <1> from <9> An inductor component listed in any one of the following. <11> When the axial direction of the inductor wiring is defined as the direction from the second surface toward the first surface, the system further comprises lead-out wiring connected to the first surface at the end of the inductor wiring in the extending direction, extending in the first direction and exposed from the outer surface of the element, The insulating layer provided on a part of the first surface of the inductor wiring is provided over a range of 80 μm or more from the periphery of the lead wiring on the first surface. <10> The inductor components listed below. <12> When the axial direction of the inductor wiring is defined as the direction from the second surface toward the first surface, the system further comprises lead-out wiring connected to the first surface at the end of the inductor wiring in the extending direction, extending in the first direction and exposed from the outer surface of the element, The insulating layer provided on a portion of the first surface of the inductor wiring is separated from the lead wiring. <10> The inductor components listed below. [Explanation of Symbols]

[0086] 1, 1A, 1B, 1C, 1D Inductor Components 10 Base Body 10a First main surface 10b Second main surface 10c~10f First to fourth sides 11 First magnetic layer 12 Second magnetic layer 15 coils 21, 21B 1st lead wiring 211 1st pillar wiring 212 Via 1 Wiring 22 2nd lead-out wiring 221 2nd pillar wiring 222 Second via wiring 30, 30B Insulating Coating 31 Top section 32 Wall 321 1st wall section 321a End face of the first wall 322 2nd wall section 322a End face of the second wall 51 First external terminal 52 Second external terminal 60 Coating membrane 70 Underlayment insulating layer Seed layer 81, 82 150 Inductor Wiring Top view (first side) of the 150a inductor wiring. 150b Inductor wiring bottom surface (second surface) 150c Inductor Wiring, First Side 150c1 Outermost surface of inductor wiring 150c2 Inductor wiring: Inner surface of the innermost circumference and the outer surface facing it 150d Inductor wiring, second side 150d1 Inner surface of the innermost circumference of the inductor wiring 151 Inner end 152 Outer edge AX coil shaft D1 1st direction D2 2nd direction h1, h2 distance

Claims

1. A base body containing a magnetic layer, A coil having an axis is placed inside the aforementioned body, The coil comprises an insulating layer that covers a portion of the outer surface of the coil, The coil has inductor wiring wound along a plane perpendicular to the axis, The inductor wiring has a first surface and a second surface that face each other in the axial direction. At least a portion of the first surface of the inductor wiring is in contact with the magnetic layer, The insulating layer is provided at least on a portion of the first surface of the inductor wiring, When the axial direction of the inductor wiring is defined as the direction from the second surface toward the first surface, the system further comprises lead-out wiring connected to the first surface at the end of the inductor wiring in the extending direction, extending in the first direction and exposed from the outer surface of the element, An inductor component in which the insulating layer provided on a part of the first surface of the inductor wiring is provided on the first surface over a range of 80 μm or more from the periphery of the lead wiring around the entire circumference of the lead wiring.

2. The inductor component according to claim 1, wherein the entire surface of the first surface of the inductor wiring is in contact with the magnetic layer.

3. The inductor component according to claim 1 or 2, wherein the entire surface of the second surface of the inductor wiring is in contact with the magnetic layer.

4. In a cross-section perpendicular to the direction of extension of the inductor wiring, The inductor wiring has two sides that connect the first surface and the second surface, The inductor component according to claim 1 or 2, wherein the insulating layer has a wall portion provided on at least one of the two sides.

5. The inductor component according to claim 1 or 2, wherein at least a portion of the inner surface of the innermost circumference of the inductor wiring is in contact with the magnetic layer.

6. When the axial direction of the inductor wiring is defined as the direction from the second surface toward the first surface, the system further comprises lead-out wiring connected to the first surface at the end of the inductor wiring in the extending direction, extending in the first direction and exposed from the outer surface of the element, The inductor component according to claim 1 or 2, wherein the insulating layer provided on a part of the first surface of the inductor wiring is separated from the lead wiring.

7. The inductor component according to claim 4, wherein, when the axial direction toward the first surface of the inductor wiring is defined as the first direction, the end face of the wall portion in the first direction is located on the side of the first surface of the inductor wiring that is located on the first direction side.

8. In a cross-section perpendicular to the direction of extension of the inductor wiring, The inductor wiring has two sides that connect the first surface and the second surface, The two sides of the inductor wiring located at the innermost circumference include the inner circumference surface of the innermost circumference and the outer circumference surface facing the inner circumference surface, The insulating layer has at least wall portions provided on each of the inner and outer surfaces, The inductor component according to claim 1 or 2, wherein, when the axial direction of the inductor wiring is defined as the direction from the second surface toward the first surface, the end face of the wall portion provided on the inner circumferential surface in the first direction is located on the side of the second direction, opposite to the first direction, than the end face of the wall portion provided on the outer circumferential surface in the first direction.

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