Inductor component and method of manufacturing an inductor component

Abstract

The present application provides an inductor component capable of improving the adhesion between a green body and an insulating layer and improving reliability, and a method for manufacturing the inductor component. The inductor component includes a green body, a coil disposed in the green body, and an insulating layer of a non-magnetic body covering at least a portion of the coil. The green body has a first magnetic layer and a second magnetic layer stacked in order along a first direction. The coil has a small-turn inductor wiring extending along a plane orthogonal to the first direction between the first magnetic layer and the second magnetic layer, and has a top surface facing the first direction, a bottom surface facing a second direction opposite to the first direction, a first side surface facing a third direction orthogonal to the first direction, and a second side surface facing a fourth direction opposite to the third direction in a first cross section orthogonal to the extending direction of the small-turn inductor wiring. The insulating layer has at least one of a portion located in a top surface portion closer to the first direction than the top surface, a first side surface portion covering the first side surface, a second side surface portion covering the second side surface, a first protruding portion protruding from the at least one portion closer to the third direction than the first side surface portion, and a second protruding portion protruding from the at least one portion closer to the fourth direction than the second side surface portion.

Description

Inductor components and methods for manufacturing inductor components Technical Field

[0001] This disclosure relates to inductor components and methods for manufacturing inductor components. Background Technology

[0002] Conventionally, as an inductor component, there is a component described in Japanese Patent Application Publication No. 2017-11185 (Patent Document 1). This inductor component includes: a blank having a magnetic layer, a coil disposed within the blank, and an insulating layer of non-magnetic material covering the coil. The coil has multiple stacked spiral wirings. Each spiral wiring has one or more turns. The insulating layer has a hole in a region corresponding to the inner magnetic circuit of the coil, and a portion of the blank is disposed within the hole.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2017-11185

[0004] However, it is known that in conventional inductor components, the following problems arise when using spiral wiring with 0.5 turns or less. Compared to spiral wiring with 1 or more turns, spiral wiring with 0.5 turns or less has a shorter curved portion, resulting in an incompletely wound shape. Therefore, compared to spiral wiring with 1 or more turns, the direction of the contact surface between the insulating layer covering the spiral wiring and the blank deviates, potentially reducing the tightness of the seal between the insulating layer and the blank in a specific direction. Consequently, for example, when the blank and the insulating layer expand or contract due to thermal loads, gaps arise between the insulating layer and the blank due to differences in expansion rates and the aforementioned weak seal in that specific direction. Moisture can penetrate these gaps, potentially accelerating the deterioration of the inductor component. Summary of the Invention

[0005] Therefore, this disclosure aims to provide an inductor component that improves the adhesion between the blank and the insulating layer and enhances reliability, as well as a method for manufacturing the inductor component.

[0006] To solve the above-mentioned problems, an inductor component according to one aspect of this disclosure includes:

[0007] It comprises: a blank, a coil disposed within the blank, and an insulating layer of non-magnetic material covering at least a portion of the coil.

[0008] The aforementioned blank has a first magnetic layer and a second magnetic layer stacked sequentially along a first direction.

[0009] The coil has a small-turn inductor wiring of 0.5 turns or less extending along a plane orthogonal to the first direction between the first magnetic layer and the second magnetic layer.

[0010] In the first cross section orthogonal to the extension direction of the wiring of the aforementioned small-turn inductor,

[0011] The aforementioned small-turn inductor wiring has: a top surface facing the first direction, a bottom surface facing a second direction opposite to the first direction, a first side surface facing a third direction orthogonal to the first direction, and a second side surface facing a fourth direction opposite to the third direction.

[0012] The insulating layer has: a portion of at least one of a top portion located in the first direction more than the top surface and a bottom portion located in the second direction more than the bottom surface; a first side portion covering the first side surface; a second side portion covering the second side surface; a first protrusion protruding from the at least one portion in a third direction more than the first side portion; and a second protrusion protruding from the at least one portion in a fourth direction more than the second side portion.

[0013] Here, for the number of turns in a small-turn inductor wiring, 0.5 turns or less refers to a state in which the center angle between the center of each end of the small-turn inductor wiring and the axis of the coil is less than 180° when viewed from the axial direction of the coil, and a non-circling state such as a straight shape or a zigzag shape.

[0014] According to the above method, due to the presence of the first protrusion and the second protrusion, the contact area between the insulating layer and the blank can be increased. Furthermore, the first protrusion and the second protrusion can penetrate deep into the blank. Therefore, the tightness of the connection between the insulating layer and the blank is improved, thereby enhancing the reliability of the inductor component.

[0015] Preferably, in one embodiment of the inductor component,

[0016] The wiring of the aforementioned small-turn inductor, which has multiple layers along the first direction,

[0017] In the first cross section described above, there are protrusions of different lengths in all of the first protrusions and the second protrusions described above.

[0018] According to the above embodiments, by extending the length of a portion of the first or second protrusion, the adhesion between the insulating layer and the blank can be further improved. Furthermore, by shortening the length of a portion of the first or second protrusion, the magnetic reluctance of the magnetic circuit can be reduced, thereby improving the efficiency of inductance acquisition.

[0019] Preferably, in one embodiment of the inductor component,

[0020] The wiring of the aforementioned small-turn inductor, which has multiple layers along the first direction,

[0021] In the first cross section, the closer the small-turn inductor wiring is to the first direction, the shorter the length of the first protrusion and the second protrusion.

[0022] According to the above embodiment, the closer the inductor wiring is to the first direction, the shorter the lengths of the first and second protrusions are. Therefore, the closer to the first direction, the wider the area of ​​the magnetic circuit of the coil. As a result, when filling the second magnetic layer into the coil from the first direction side in the second direction during manufacturing, it becomes easier to fill the second magnetic layer into the coil, the filling rate is increased, and the inductance can be improved.

[0023] Preferably, in one embodiment of the inductor component, in the first cross-section, at least one of the first protrusion and the second protrusion is inclined in the second direction.

[0024] According to the above embodiment, since at least one of the first and second protrusions is inclined in the second direction, filling the second magnetic layer into the coil from the first direction side in the second direction during manufacturing becomes smoother. Furthermore, since the protrusions are inclined in the second direction, after filling the second magnetic layer, it is possible to prevent the second magnetic layer from detaching in the first direction, thereby further improving the adhesion between the insulating layer and the blank.

[0025] Preferably, in one embodiment of the inductor component, in the first cross-section, at least one of the first protrusion and the second protrusion is inclined in the first direction.

[0026] According to the above embodiment, at least one of the first protrusion and the second protrusion is inclined in the first direction. Therefore, when filling the first magnetic layer into the coil from the second direction side in the first direction during manufacturing, the filling of the first magnetic layer into the coil becomes smooth. In addition, since the protrusion is inclined in the first direction, after the first magnetic layer is filled, it can prevent the first magnetic layer from falling off in the second direction, and can further improve the adhesion between the insulating layer and the blank.

[0027] Preferably, in one embodiment of the inductor component,

[0028] The wiring of the aforementioned small-turn inductor, which has multiple layers along the first direction,

[0029] The aforementioned coil is formed by connecting multiple small-turn inductors in series to create one or more turns.

[0030] In the first cross section described above, all of the first protrusions and the second protrusions are located in either the inner magnetic circuit or the outer magnetic circuit of the coil.

[0031] According to the above embodiments, the adhesion between the insulating layer and the blank can be further improved.

[0032] Preferably, in one embodiment of the inductor component, in the first cross-section, the length of the first protrusion is different from the length of the second protrusion.

[0033] According to the above embodiments, by extending the length of one of the first or second protrusions, the adhesion between the insulating layer and the blank can be further improved. Furthermore, by shortening the length of the other of the first or second protrusions, the magnetic reluctance of the magnetic circuit can be reduced, thereby improving the efficiency of inductance acquisition.

[0034] Preferably, in one embodiment of the inductor component,

[0035] The aforementioned small-turn inductor wiring has n layers along the first direction, where n≥2.

[0036] The material of the insulating layer covering the small-turn inductor wiring of the first layer is different from the material of the insulating layer covering the small-turn inductor wiring of the m-th layer, wherein 2≤m≤n.

[0037] According to the above embodiments, design freedom can be improved. Preferably, the material of the insulating layer covering the small-turn inductor wiring of the first layer is selected based on factors such as peel strength and stress from the substrate. On the other hand, the material of the insulating layer covering the small-turn inductor wiring of the m-th layer is preferably selected based on factors such as laser performance, photolithographic resolution, and coverage of step differences.

[0038] Preferably, in one embodiment of the inductor component,

[0039] The first magnetic layer and the second magnetic layer mentioned above contain magnetic powder.

[0040] The contact surface between the second magnetic layer and the first magnetic layer includes the cut surface of the magnetic powder, and the contact surface between the first magnetic layer and the second magnetic layer includes the surface of the magnetic powder.

[0041] Here, the surface of magnetic powder refers to the surface of the uncut magnetic powder, such as a sphere, excluding the cut surface.

[0042] According to the above embodiment, the contact surface of the second magnetic layer can be made flat, thus facilitating the transmission of pressure to the first magnetic layer during manufacturing when filling the first magnetic layer towards the second magnetic layer. Therefore, the filling rate of the magnetic powder in the first magnetic layer can be increased, resulting in improved inductance.

[0043] Preferably, in one embodiment of the inductor component,

[0044] The aforementioned insulating layer covers the wiring of the small-turn inductor and extends continuously along the extension direction of the wiring. The insulating layer has a first portion that covers the wiring of the small-turn inductor and a second portion that does not cover the wiring of the small-turn inductor.

[0045] In the second section orthogonal to the extension direction of the second part mentioned above,

[0046] The second part above has:

[0047] The main body portion exists at a position corresponding to the extension direction of the wiring of the aforementioned small-turn inductor;

[0048] The portion located at least one of the top portion which is closer to the first direction than the main body portion and the bottom portion which is closer to the second direction than the main body portion.

[0049] A first protrusion protruding from at least one of the aforementioned portions in a fifth direction orthogonal to the aforementioned first direction, which is more prominent than the aforementioned main body portion; and

[0050] A second protrusion protrudes from at least one of the aforementioned portions in a sixth direction, which is opposite to the fifth direction described above, compared to the aforementioned main portion.

[0051] According to the above embodiment, since a second part is provided in addition to the first part, the contact area between the insulating layer and the blank can be further increased by the second part. In addition, the first protrusion and the second protrusion of the second part can penetrate into the blank. As a result, the tightness of the connection between the insulating layer and the blank is further improved, and the reliability of the inductor component can be further improved.

[0052] Furthermore, by setting up a dummy insulating layer like the second part, when viewed from the first direction, other inductor wirings are staggered and stacked relative to each other by a portion of the small-turn inductor wirings. When viewed from the first direction, other inductor wirings can overlap not only with the first part but also with the second part, thus ensuring the flatness of the inductor wirings.

[0053] Preferably, in one embodiment of the inductor component, other inductor wiring is provided at a location that overlaps at least a portion of the small-turn inductor wiring when viewed from the first direction.

[0054] According to the above embodiment, since other inductor wiring will not be unnecessarily extended in a plane direction orthogonal to the first direction, the volume of the blank can be increased.

[0055] Preferably, in one embodiment of the inductor component, in the first direction, the first magnetic layer or the second magnetic layer, which is located at the same position as the small-turn inductor wiring, overlaps with a portion of the other inductor wiring when viewed from a direction orthogonal to the first direction.

[0056] According to the above embodiments, the volume of the magnetic layer (magnetic circuit) can be increased.

[0057] Preferably, in one embodiment of the inductor component, the first magnetic layer or the second magnetic layer that overlaps with a portion of the other inductor wiring is a second magnetic layer located in the first direction of the other inductor wiring.

[0058] According to the above embodiment, the volume of the magnetic layer (magnetic circuit) can be increased. The filling of the second magnetic layer is also easier during manufacturing.

[0059] Preferably, in one embodiment of the inductor component, the first magnetic layer or the second magnetic layer that overlaps with a portion of the other inductor wiring is a first magnetic layer located in the second direction of the other inductor wiring.

[0060] According to the above embodiment, the volume of the magnetic layer (magnetic circuit) can be increased. Filling of the first magnetic layer is also easier during manufacturing.

[0061] Preferably, in one embodiment of the method for manufacturing an inductor component, the following is provided:

[0062] The process of forming a small-turn inductor wiring of 0.5 turns or less, wherein, in a first cross section orthogonal to the extension direction, the small-turn inductor wiring has: a top surface facing the first direction, a bottom surface facing the second direction opposite to the first direction, a first side surface facing the third direction orthogonal to the first direction, and a second side surface facing the fourth direction opposite to the third direction.

[0063] The process of forming an insulating layer to have at least one of a top portion located further in the first direction than the top surface and a bottom portion located further in the second direction than the bottom surface in the first cross section, a first side portion covering the first side surface, a second side portion covering the second side surface, a first protrusion protruding from at least one of the above-mentioned portions in a third direction than the first side portion, and a second protrusion protruding from at least one of the above-mentioned portions in a fourth direction than the second side portion; and the process of forming an insulating layer to have at least one of the above-mentioned portions in a fourth direction in the first cross section having a top portion located further in the first direction than the top surface and a bottom portion located further in the second direction than the bottom surface; and the process of forming an insulating layer to have at least one of the above-mentioned portions in the first cross section having a top portion located further in the first direction than the top surface and a bottom portion located further in the second direction than the bottom surface; and the process of forming an insulating layer ...

[0064] The process of stacking a first magnetic layer and a second magnetic layer along the first direction to hold the small-turn inductor wiring and the insulating layer to form a blank.

[0065] According to the above implementation method, the adhesion between the insulating layer and the magnetic layer is improved.

[0066] Preferably, in one embodiment of the method for manufacturing an inductor component,

[0067] In the process of forming the wiring of the small-turn inductor, a dummy wiring is also formed at a position that can overlap with the first protrusion or the second protrusion when viewed from the first direction.

[0068] After the process of forming the wiring of the small-turn inductor described above, there is also a process of removing the aforementioned dummy wiring.

[0069] In the process of forming the above-mentioned blank, the first magnetic layer or the second magnetic layer is also filled in the position where the above-mentioned dummy wiring has been removed.

[0070] According to the above embodiments, a magnetic layer that is in close contact with the first protrusion or the second protrusion can be manufactured at low cost.

[0071] According to the inductor component and the manufacturing method of the inductor component as one aspect of this disclosure, improving the adhesion between the blank and the insulating layer can improve reliability. Attached Figure Description

[0072] Figure 1 is a top view showing a first embodiment of the inductor component.

[0073] Figure 2A is a cross-sectional view of Figure 1 (AA).

[0074] Figure 2B is a sectional view of Figure 1 (BB ​​section).

[0075] Figure 3 is an enlarged view of part A of Figure 2B.

[0076] Figure 4A is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0077] Figure 4B is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0078] Figure 4C is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0079] Figure 4D is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0080] Figure 4E is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0081] Figure 4F is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0082] Figure 4G is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0083] Figure 4H is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0084] Figure 4I is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0085] Figure 4J is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0086] Figure 5A is a cross-sectional view showing a second embodiment of the inductor component.

[0087] Figure 5B is a cross-sectional view showing a second embodiment of the inductor component.

[0088] Figure 6 is a cross-sectional view showing a third embodiment of the inductor component.

[0089] Figure 7 is a top view showing a fourth embodiment of the inductor component.

[0090] Figure 8 is a cross-sectional view AA of Figure 7.

[0091] Figure 9A is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0092] Figure 9B is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0093] Figure 9C is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0094] Figure 9D is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0095] Figure 9E is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0096] Figure 9F is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0097] Figure 9G is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0098] Figure 9H is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0099] Figure 9I is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0100] Figure 9J is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0101] Figure 9K is an explanatory diagram illustrating the manufacturing process of an inductor component.

[0102] Figure 10 is a cross-sectional view showing a fifth embodiment of the inductor component.

[0103] Figure 11 is a cross-sectional view showing a sixth embodiment of the inductor component.

[0104] Explanation of reference numerals in the attached figures

[0105] 1, 1D, 1E, 1F…Inductor components; 10…Bulkhead; 10a…First main surface; 10b…Second main surface; 11…First magnetic layer; 11a…Contact surface; 12…Second magnetic layer; 12a…Contact surface; 15, 15D, 15F…Coils; 21A, 21B, 21D, 21F, 21G…First, second, third, fifth, and sixth inductor wiring (small-turn inductor wiring); 211…Top surface; 212…Bottom surface; 213…First side surface; 214…Second side surface; 22D…Fourth inductor wiring (other inductor wiring); 31, 32, 33…First, second, and third columnar wiring; 35…Through-hole wiring; 41, 42, 43…First, second, and third external terminals; 50…Coating film; 51, 52, 53… 1. Second and third vertical wiring; 60, 60A, 60B, 60C, 60D, 60E, 60F… Insulation layer; 61… Top surface portion; 62… Bottom surface portion; 63… First side surface portion; 64… Second side surface portion; 65… First protrusion on top surface; 66… Second protrusion on top surface; 67… First protrusion on bottom surface; 68… Second protrusion on bottom surface; 61D, 61E, 61F… First insulation portion; 61D1, 61D2… First and second parts; 62D, 62E, 62F… Second insulation portion; 90… Main body portion; 91… Top surface portion; 92… Bottom surface portion; 95… First protrusion on top surface; 96… Second protrusion on top surface; 97… First protrusion on bottom surface; 98… Second protrusion on bottom surface; 100… Magnetic powder; 101… Resin. Detailed Implementation

[0106] The following is a detailed description of an inductor component and a method for manufacturing the inductor component, which are embodiments of the present disclosure, through illustrated examples. Furthermore, the accompanying drawings contain some schematic representations and may not always reflect actual dimensions or proportions.

[0107] <First Implementation>

[0108] (structure)

[0109] Figure 1 is a top view showing a first embodiment of the inductor component. Figure 2A is a cross-sectional view of Figure 1 at section AA. Figure 2B is a cross-sectional view of Figure 1 at section BB.

[0110] Inductor component 1 is used in electronic devices such as personal computers, DVD players, digital cameras, TVs, mobile phones, and automotive electronics, and is, for example, a component with an overall cuboid shape. However, the shape of inductor component 1 is not particularly limited, and it can also be cylindrical, polygonal cylindrical, frustum conical, or polygonal frustum conical.

[0111] As shown in Figures 1, 2A, and 2B, the inductor component 1 includes: a blank body 10, a coil 15 disposed within the blank body 10, an insulating layer 60 of non-magnetic material covering at least a portion of the coil 15, a first vertical wiring 51, a second vertical wiring 52, and a third vertical wiring 53 disposed within the blank body 10 such that their end faces are exposed from a first main surface 10a of the blank body 10, and a first external terminal 41, a second external terminal 42, and a third external terminal 43 exposed on the first main surface 10a of the blank body 10. In Figure 1, for convenience, the first to third external terminals 41 to 43 are indicated by double-dotted lines.

[0112] In the figure, the thickness direction of inductor component 1 is defined as the Z direction, the positive Z direction as the top, and the negative Z direction as the bottom. In a plane orthogonal to the Z direction of inductor component 1, the length direction of the long side of inductor component 1 and the direction in which the first external terminal 41 and the second external terminal 42 are arranged is defined as the X direction, and the width direction of inductor component 1, which is orthogonal to the length direction, is defined as the Y direction.

[0113] The blank 10 has: a first main surface 10a and a second main surface 10b, 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.

[0114] The first main surface 10a and the second main surface 10b are arranged on opposite sides in the Z direction, with the first main surface 10a arranged in the positive Z direction and the second main surface 10b arranged in the negative Z direction. The first side surface 10c and the second side surface 10d are arranged on opposite sides in the X direction, with the first side surface 10c arranged in the negative X direction and the second side surface 10d arranged in the positive X direction. The third side surface 10e and the fourth side surface 10f are arranged on opposite sides in the Y direction, with the third side surface 10e arranged in the negative Y direction and the fourth side surface 10f arranged in the positive Y direction.

[0115] The blank 10 has a first magnetic layer 11 and a second magnetic layer 12 stacked sequentially along the positive Z direction. The word "sequentially" only indicates the positional relationship between the first magnetic layer 11 and the second magnetic layer 12, and has nothing to do with the formation order of the first magnetic layer 11 and the second magnetic layer 12.

[0116] 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 epoxy-based, benzene-based, liquid crystal polymer-based, polyimide-based, acrylic-based, or an organic insulating material composed of mixtures thereof. The magnetic powder is, for example, an FeSi alloy such as FeSiCr, an FeCo alloy, an Fe alloy such as NiFe, or an amorphous alloy thereof. Therefore, compared to a magnetic layer composed of ferrite, the magnetic powder improves the DC superposition characteristics, and the resin provides insulation between the magnetic powder particles, thus reducing losses (iron losses) at high frequencies. Furthermore, the magnetic layer may also be a sintered body of ferrite or magnetic powder that does not contain organic resin.

[0117] The coil 15 has a first inductor wiring 21A with less than 0.5 turns and a second inductor wiring 21B with less than 0.5 turns. The first inductor wiring 21A and the second inductor wiring 21B are respectively equivalent to the "small-turn inductor wiring" described in the claims.

[0118] The first inductor wiring 21A and the second inductor wiring 21B extend between the first magnetic layer 11 and the second magnetic layer 12 along a plane orthogonal to the positive Z direction. Specifically, the first magnetic layer 11 exists in the negative Z direction of the first inductor wiring 21A and the second inductor wiring 21B, and the second magnetic layer 12 exists in the positive Z direction and in a direction orthogonal to the positive Z direction of the first inductor wiring 21A and the second inductor wiring 21B.

[0119] When viewed from the Z direction, the first inductor wiring 21A extends in a straight line along the X direction. When viewed from the Z direction, a portion of the second inductor wiring 21B extends in a straight line along the X direction, while the remaining portion extends in a straight line along the Y direction, that is, it extends in an L-shape.

[0120] Preferably, the thickness of the first and second inductor wirings 21A and 21B is, for example, 40 μm or more and 120 μm or less. As an example of the first and second inductor wirings 21A and 21B, the thickness is 35 μm, the wiring width is 50 μm, and the maximum space between the wirings is 200 μm.

[0121] The first inductor wiring 21A and the second inductor wiring 21B are made of conductive materials, such as low-resistance metals like Cu, Ag, Au, and Al. In this embodiment, the inductor component 1 has only one layer of first and second inductor wiring 21A and 21B, which enables the inductor component 1 to have a low height. Furthermore, the inductor wiring can also be a two-layer structure consisting of a seed layer and an electroplated layer; the seed layer can also contain Ti or Ni.

[0122] The first end 21a of the first inductor wiring 21A is electrically connected to the first vertical wiring 51, and the second end 21b of the first inductor wiring 21A is electrically connected to the second vertical wiring 52. That is, the first inductor wiring 21A has pad portions with large line widths at the first and second ends 21a and 21b, and is directly connected to the first and second vertical wirings 51 and 52 at the pad portions.

[0123] The first end 22a of the second inductor wiring 21B is electrically connected to the third vertical wiring 53, and the second end 22b of the second inductor wiring 21B is electrically connected to the second vertical wiring 52. That is, the second inductor wiring 21B has a pad portion at its first end 22a, and this pad portion is directly connected to the third vertical wiring 53. The second end 22b of the second inductor wiring 21B is shared with the second end 21b of the first inductor wiring 21A.

[0124] When viewed from the Z direction, the first end 21a of the first inductor wiring 21A and the first end 22a of the second inductor wiring 21B are located on the first side 10c side of the blank 10. When viewed from the Z direction, the second end 21b of the first inductor wiring 21A and the second end 22b of the second inductor wiring 21B are located on the second side 10d side of the blank 10.

[0125] A first lead wire 201 is connected to each end of the first end 21a of the first inductor wiring 21A and the first end 22a of the second inductor wiring 21B, and the first lead wire 201 is exposed from the first side 10c. A second lead wire 202 is connected to the second end 21b of the first inductor wiring 21A and the second end 22b of the second inductor wiring 21B, and the second lead wire 202 is exposed from the second side 10d.

[0126] The first lead wire 201 and the second lead wire 202 are added during the manufacturing process of the inductor component 1 after the shapes of the first and second inductor wires 21A and 21B are formed, and are connected to the power supply wires during electroplating. Electroplating can be easily performed on the inductor substrate before the inductor component 1 is monolithically assembled using these power supply wires, and the distance between the wires can be narrowed. Furthermore, by performing additional electroplating to narrow the distance between the first and second inductor wires 21A and 21B, the magnetic coupling of the first and second inductor wires 21A and 21B can be improved. In addition, by providing the first lead wire 201 and the second lead wire 202, strength can be ensured during the cutting of the blank 10 when the inductor component 1 is monolithically assembled, and the yield rate during manufacturing can be improved.

[0127] The first to third vertical wirings 51 to 53 extend from the inductor wirings 21A and 21B along the Z direction, penetrating the interior of the second magnetic layer 12. The first vertical wiring 51 extends from the upper surface of the first end 21a of the first inductor wiring 21A to the first main surface 10a of the blank 10, with its end face exposed from the first main surface 10a. The second vertical wiring 52 extends from the upper surface of the second end 21b of the first inductor wiring 21A to the first main surface 10a of the blank 10, with its end face exposed from the first main surface 10a. The third vertical wiring 53 extends from the upper surface of the first end 22a of the second inductor wiring 21B to the first main surface 10a of the blank 10, with its end face exposed from the first main surface 10a.

[0128] Therefore, the first vertical wiring 51, the second vertical wiring 52, and the third vertical wiring 53 extend in a straight line from the first inductor wiring 21A and the second inductor wiring 21B to the end face exposed from the first main surface 10a in a direction orthogonal to the first main surface 10a. This allows for the connection of the first external terminal 41, the second external terminal 42, the third external terminal 43, and the first inductor wiring 21A and the second inductor wiring 21B with a shorter distance, and enables the inductor component 1 to achieve low resistance and high inductance. The first to third vertical wirings 51 to 53 are made of a conductive material, for example, the same material as the inductor wirings 21A and 21B.

[0129] The first vertical wiring 51 has a via wiring 35 penetrating the interior of the insulating layer 60, and a first columnar wiring 31 extending upward from the via wiring 35 and penetrating the interior of the second magnetic layer 12. The second vertical wiring 52 has a via wiring 35 penetrating the interior of the insulating layer 60, and a second columnar wiring 32 extending upward from the via wiring 35 and penetrating the interior of the second magnetic layer 12. The third vertical wiring 53 has a via wiring 35 penetrating the interior of the insulating layer 60, and a third columnar wiring 33 extending upward from the via wiring 35 and penetrating the interior of the second magnetic layer 12. The via wiring 35 is a conductor with a linewidth (diameter, cross-sectional area) smaller than that of the columnar wirings 31-33.

[0130] The first to third external terminals 41 to 43 are disposed on the first main surface 10a of the blank 10. The first to third external terminals 41 to 43 are made of conductive materials, for example, a three-layer structure in which Cu with low resistance and excellent stress resistance, Ni with excellent corrosion resistance, and Au with excellent solder wettability and reliability are arranged in this order from the inside to the outside.

[0131] The first external terminal 41 contacts the end face of the first vertical wiring 51 exposed from the first main surface 10a of the blank 10 and is electrically connected to the first vertical wiring 51. Thus, the first external terminal 41 is electrically connected to the first end 21a of the first inductor wiring 21A. The second external terminal 42 contacts the end face of the second vertical wiring 52 exposed from the first main surface 10a of the blank 10 and is electrically connected to the second vertical wiring 52. Thus, the second external terminal 42 is electrically connected to the second end 21b of the first inductor wiring 21A and the second end 22b of the second inductor wiring 21B. The third external terminal 43 contacts the end face of the third vertical wiring 53 and is electrically connected to the third vertical wiring 53, and is electrically connected to the first end 22a of the second inductor wiring 21B.

[0132] The insulating layer 60 is made of an insulating material that does not contain magnetic materials. Examples of insulating layer 60 include epoxy resin, benzene resin, polyimide resin, liquid crystal polymer, combinations thereof, organic resins, glass, sintered bodies such as alumina, thin films such as silicon oxide films, silicon nitride films, and silicon oxynitride films.

[0133] As shown in Figure 2B, in a first cross section orthogonal to the extension directions of the first inductor wiring 21A and the second inductor wiring 21B, the first inductor wiring 21A and the second inductor wiring 21B respectively have: a top surface 211 facing the positive Z direction, a bottom surface 212 facing the Z direction, a first side surface 213 facing the negative Y direction, and a second side surface 214 facing the Y direction.

[0134] The positive Z-direction corresponds to the "first direction" as stated in the claims; the negative Z-direction corresponds to the "second direction opposite to the first direction" as stated in the claims; the negative Y-direction corresponds to the "third direction orthogonal to the first direction" as stated in the claims; and the Y-direction corresponds to the "fourth direction opposite to the third direction" as stated in the claims. Hereinafter, it may be referred to as the first to fourth directions.

[0135] The insulating layer 60 has: a top portion 61 located in a first direction more than the top surface 211; a bottom portion 62 located in a second direction more than the bottom surface 212; a first side portion 63 covering a first side surface 213; a second side surface portion 64 covering a second side surface 214; a top surface-side first protrusion 65 protruding from the top portion 61 in a third direction more than the first side surface portion 63; a top surface-side second protrusion 66 protruding from the top portion 61 in a fourth direction more than the second side surface portion 64; a bottom surface-side first protrusion 67 protruding from the bottom portion 62 in a third direction more than the first side surface portion 63; and a bottom surface-side second protrusion 68 protruding from the bottom portion 62 in a fourth direction more than the second side surface portion 64. The top portion 61 contacts the top surface 211, the first side surface portion 63, and the second side surface portion 64, and the bottom portion 62 contacts the bottom surface 212, the first side surface portion 63, and the second side surface portion 64.

[0136] According to the above structure, due to the presence of first protrusions 65 and 67 and second protrusions 66 and 68, the contact area between the insulating layer 60 and the blank 10 can be increased. Furthermore, the first protrusions 65 and 67 and the second protrusions 66 and 68 can penetrate deep into the blank 10. Therefore, the tightness of the connection between the insulating layer 60 and the blank 10 is improved, and the reliability of the inductor component 1 is enhanced.

[0137] Specifically, the first and second inductor wirings 21A and 21B have fewer than 0.5 turns. Compared to inductor wiring with more than 1 turn, the curved portion is shorter, resulting in an incompletely wound shape. Therefore, assuming the first protrusions 65 and 67 and the second protrusions 66 and 68 are not present, in inductor wiring with fewer than 0.5 turns, compared to inductor wiring with more than 1 turn, the orientation of the contact surface between the insulating layer covering the inductor wiring and the blank deviates, and the tightness of the insulation layer in a certain direction may be reduced.

[0138] In contrast, by having first protrusions 65 and 67 and second protrusions 66 and 68, the deviation in the direction of the contact surface between the insulating layer 60 covering the wirings 21A and 21B of the first and second inductors and the blank 10 is reduced, thereby improving the tightness of the insulating layer 60 and the blank 10 in a specific direction.

[0139] Therefore, for example, even if the blank 10 and the insulating layer 60 expand or contract due to heat load, the generation of gap between the insulating layer 60 and the blank 10 can be reduced, moisture can be prevented from entering the gap, and the deterioration of the inductor component 1 can be suppressed.

[0140] Preferably, in the first cross-section, the length of at least one of the first protrusions 65, 67 is different from the length of at least one of the second protrusions 66, 68. In this case, the length of at least one of the first protrusions 65, 67 may be different from the length of at least one of the second protrusions 66, 68 in the same insulating layer 60, or the length of at least one of the first protrusions 65, 67 may be different from the length of at least one of the second protrusions 66, 68 in all insulating layers 60.

[0141] According to the above structure, by extending the length of one of the first or second protrusions, the adhesion between the insulating layer 60 and the blank 10 can be further improved. Furthermore, by shortening the length of the other of the first or second protrusions, the magnetic reluctance of the magnetic circuit can be reduced, thereby improving the efficiency of inductance acquisition.

[0142] Preferably, in the first cross-section, the lengths of the first protrusions 65 and 67 are the same as the lengths of the second protrusions 66 and 68. In this case, the lengths of the first protrusions 65 and 67 can be the same as the lengths of the second protrusions 66 and 68 in the same insulating layer 60, or the lengths of the first protrusions 65 and 67 can be the same as the lengths of the second protrusions 66 and 68 in all insulating layers 60.

[0143] According to the above structure, by making the lengths of the first and second protrusions the same, the insulating layer 60 can be easily manufactured.

[0144] Figure 3 is an enlarged view of part A of Figure 2B. As shown in Figure 3, the first magnetic layer 11 and the second magnetic layer 12 respectively contain magnetic powder 100 and resin 101 containing magnetic powder 100. Preferably, the contact surface 12a between the second magnetic layer 12 and the first magnetic layer 11 contains a cut surface of magnetic powder 100, and the contact surface 11a between the first magnetic layer 11 and the second magnetic layer 12 contains the surface of magnetic powder 100.

[0145] According to the above structure, the contact surface 12a of the second magnetic layer 12 can be made flat, so when filling the first magnetic layer 11 towards the second magnetic layer 12 during manufacturing, it is easy to transmit pressure to the first magnetic layer 11. Therefore, the filling rate of the magnetic powder 100 in the first magnetic layer 11 can be increased, resulting in improved inductance.

[0146] In the first embodiment, the insulating layer has a top surface and a bottom surface, but it is sufficient to have at least one of the top surface and the bottom surface, as long as the first protrusion and the second protrusion protrude from the at least one of the bottom surfaces.

[0147] In the first embodiment, the inductor wiring is one layer, but it can also be two or more layers. If it is one layer, the thickness of the inductor component can be reduced. If it is two or more layers, the number of turns of the inductor wiring can be increased, thus improving the inductance. Furthermore, when the inductor wiring is two or more layers, at least one of them can be a small-turn inductor wiring. That is, at least one inductor wiring can be 0.5 turns or less, while other inductor wiring can be more than 0.5 turns or less.

[0148] Here, for example, when adding inductor wiring, the inductor wiring can be stacked one layer, two layers, up to m layers (m is a natural number greater than 3). In this case, the first direction (stacking direction) can be determined by the wiring shape, etc. For example, in the manufacturing process of inductor wiring, the bottom surface is generally flat and the top surface is curved. Therefore, by stacking the next layer on the curved side of the inductor wiring, the first direction can be said to be from the flat side of the inductor wiring towards the curved side. For example, in the manufacturing process, the diameter of the via wiring connecting the inductor wirings is larger on the top side than on the bottom side. Therefore, since the via wiring is stacked on the side with the larger diameter, the first direction can be said to be from the connection surface of the smaller diameter via wiring towards the connection surface of the larger diameter. For example, when using a seed layer to form the inductor wiring, the first direction can be said to be from the side with the seed layer towards the side without the seed layer. Furthermore, the above method for determining the first direction can be applied even in the case of a single layer.

[0149] (Manufacturing method)

[0150] Next, the manufacturing method of inductor component 1 will be described. Figures 4A to 4J correspond to the BB section of Figure 1 (Figure 2B).

[0151] As shown in Figure 4A, a substrate 70 is prepared. The substrate 70 is made of inorganic materials such as ceramics, glass, or silicon. A copper foil 80 is disposed on the main surface of the substrate 70, and then a first insulating layer 71 is coated on the copper foil 80 and cured.

[0152] As shown in Figure 4B, a seed layer (Ti / Cu, not shown) is formed on the first insulating layer 71 by a known method such as sputtering or vapor deposition. Then, a DFR (dry film resist) 75 is attached, and a specified pattern is formed on the DFR 75 using a photolithography method.

[0153] As shown in Figure 4C, power is supplied to the seed layer, and a first inductor wiring 21A, a second inductor wiring 21B, and a dummy wiring 81 are formed on the first insulating layer 71 using electroplating. Then, the DFR 75 is stripped, and the seed layer is etched. This creates a gap between the first inductor wiring 21A, the second inductor wiring 21B, and the dummy wiring 81.

[0154] As shown in Figure 4D, a second insulating layer 72 is applied to the first inductor wiring 21A, the second inductor wiring 21B, and the dummy wiring 81, and then cured. At this time, the second insulating layer 72 also fills the aforementioned gaps. Then, a laser is used to irradiate the second insulating layer 72 to form an opening, exposing the dummy wiring 81. At this time, a portion of the second insulating layer 72 overlaps with the dummy wiring 81. This overlapping portion of the second insulating layer 72 corresponds to the first protrusion on the top surface and the second protrusion on the top surface. Here, the central portion of the second insulating layer 72 on the dummy wiring 81 may not be removed; for example, laser irradiation can be performed along the outer periphery of the dummy wiring 81 to form an annular opening. This shortens the laser irradiation time. Furthermore, the central portion of the second insulating layer 72 on the dummy wiring 81 can be removed by peeling it off when removing the dummy wiring 81.

[0155] Then, although not shown, an opening is formed in the second insulating layer 72 to expose a portion of the first inductor wiring 21A and the second inductor wiring 21B, and a seed layer is formed on the second insulating layer 72. The DFR is then reattached, and a predetermined pattern is formed on the DFR using photolithography. The predetermined pattern consists of through holes corresponding to the positions of the first pillar wiring 31, the second pillar wiring 32, and the third pillar wiring 33 on the first inductor wiring 21A and the second inductor wiring 21B. Electroplating is used to form via wiring 35, the first pillar wiring 31, the second pillar wiring 32, and the third pillar wiring 33 on the first inductor wiring 21A and the second inductor wiring 21B. Then, the DFR is peeled off, and the seed layer is etched.

[0156] Furthermore, a DFR is provided to protect the first columnar wiring 31, the second columnar wiring 32, and the third columnar wiring 33. Then, as shown in FIG4E, the dummy wiring 81 is etched to remove the DFR. As a result, the top surface portion 61, the top surface side first protrusion 65, the top surface side second protrusion 66, the first side surface portion 63, and the second side surface portion 64 of the insulating layer 60 are formed.

[0157] As shown in Figure 4F, a portion of the first insulating layer 71 is irradiated with a laser to form an opening. This forms the bottom portion 62, the first protrusion 67 on the bottom side, and the second protrusion 68 on the bottom side of the insulating layer 60. At this time, a copper foil 80 is used as a laser termination layer. Alternatively, the copper foil 80 may not be provided, and the first insulating layer 71 may be opened using a laser for each portion of the substrate. Alternatively, the first insulating layer 71 may be patterned from the beginning using laser processing, photolithography, or other patterning techniques.

[0158] As shown in Figure 4G, the magnetic sheet that will become the second magnetic layer 12 is pressed from above the main surface of the substrate 70 toward the first inductor wiring 21A and the second inductor wiring 21B, covering the first inductor wiring 21A, the second inductor wiring 21B, the first columnar wiring 31, the second columnar wiring 32, and the third columnar wiring 33. Then, the upper surface of the second magnetic layer 12 is ground so that the end faces of the first columnar wiring 31, the second columnar wiring 32, and the third columnar wiring 33 are exposed from the upper surface of the second magnetic layer 12.

[0159] As shown in Figure 4H, the substrate 70 and copper foil 80 are removed by grinding. At this time, a portion of the first insulating layer 71 may also be removed. Then, other magnetic sheets, which are pressed from below the first inductor wiring 21A and the second inductor wiring 21B toward the first inductor wiring 21A and the second inductor wiring 21B to form the first magnetic layer 11, are used to cover the first inductor wiring 21A and the second inductor wiring 21B. Then, the first magnetic layer 11 is ground to a predetermined thickness.

[0160] As shown in Figure 4I, the inductor component 1 is monolithically processed along the cutting line D, and then the first external terminal 41, the second external terminal 42, and the third external terminal 43 are formed. Thus, as shown in Figure 4J, the inductor component 1 is manufactured.

[0161] The above-mentioned manufacturing method for the inductor component includes the following steps: forming a first inductor wiring 21A and a second inductor wiring 21B, forming an insulating layer 60, and forming a blank 10.

[0162] In the process of forming the first inductor wiring 21A and the second inductor wiring 21B, the first inductor wiring 21A and the second inductor wiring 21B are formed in a first cross section orthogonal to the extension direction, having a top surface, a bottom surface, a first side surface, and a second side surface, with 0.5 turns or less.

[0163] In the process of forming the insulating layer 60, the insulating layer 60 is formed so that it has a top surface portion 61, a bottom surface portion 62, a first side surface portion 63, a second side surface portion 64, a top surface side first protrusion 65, a top surface side second protrusion 66, a bottom surface side first protrusion 67, and a bottom surface side second protrusion 68 in a first cross section.

[0164] In the process of forming the blank 10, the first magnetic layer 11 and the second magnetic layer 12 are stacked along the first direction in such a way as to clamp the first inductor wiring 21A and the second inductor wiring 21B to form the blank 10.

[0165] According to the above structure, the adhesion between the insulating layer 60 and the magnetic layers 11 and 12 is improved.

[0166] Preferably, in the process of forming the first inductor wiring 21A and the second inductor wiring 21B, a dummy wiring 81 is also formed at a position that overlaps with the first protrusion 65 or the second protrusion 66 when viewed from the first direction. After the process of forming the first inductor wiring 21A and the second inductor wiring 21B, a process of removing the dummy wiring 81 is also included. In the process of forming the blank 10, a second magnetic layer 12 is also filled at the position where the dummy wiring 81 has been removed. Alternatively, a first magnetic layer 11 may be filled instead of a second magnetic layer 12.

[0167] Based on the above structure, a magnetic layer that is in close contact with the first protrusion 65 or the second protrusion 66 can be manufactured at low cost.

[0168] <Second Implementation>

[0169] Figures 5A and 5B are cross-sectional views showing a second embodiment of the inductor component. The second embodiment differs from the first embodiment in that the protrusion is inclined. This difference in structure will be described below. Other structures are the same as in the first embodiment, and the same reference numerals are used as in the first embodiment, with their descriptions omitted.

[0170] As shown in Figure 5A, in the insulating layer 60A, in the first cross-section, the first protrusion 65 and the second protrusion 66 on the top surface side are inclined in the second direction (negative Z direction). The first protrusion 65 and the second protrusion 66 on the top surface side are located further in the second direction than the top surface 211 of the first inductor wiring 21A.

[0171] According to the above structure, the first protrusion 65 and the second protrusion 66 on the top surface are inclined in the second direction. Therefore, when filling the second magnetic layer 12 from the first direction side of the coil 15 in the second direction during manufacturing, the filling of the second magnetic layer 12 into the coil 15 becomes smooth. In addition, since the first protrusion 65 and the second protrusion 66 on the top surface are inclined in the second direction, after the second magnetic layer 12 is filled, it can prevent the second magnetic layer 12 from falling off in the first direction, which can further improve the adhesion between the insulating layer 60A and the blank 10.

[0172] Furthermore, in all the first protrusions and the second protrusions, at least one of the first protrusions and the second protrusions may be inclined in the second direction.

[0173] Alternatively, as shown in Figure 5B, in the insulating layer 60B, in the first cross-section, the first protrusion 67 on the bottom surface and the second protrusion 68 on the bottom surface can also be inclined in the first direction (Z direction). The first protrusion 67 on the bottom surface and the second protrusion 68 on the bottom surface are located further in the first direction than the bottom surface 212 of the first inductor wiring 21A.

[0174] According to the above structure, since the first protrusion 67 and the second protrusion 68 on the bottom side are inclined in the first direction, filling the first magnetic layer 11 into the coil 15 from the second direction side in the first direction during manufacturing becomes smooth. Furthermore, since the first protrusion 67 and the second protrusion 68 on the bottom side are inclined in the first direction, after filling the first magnetic layer 11, it can prevent the first magnetic layer 11 from falling off in the second direction, further improving the adhesion between the insulating layer 60B and the blank 10.

[0175] Furthermore, in all the first protrusions and the second protrusions, at least one of the first protrusions and the second protrusions may be inclined in the first direction.

[0176] <Third Implementation Method>

[0177] Figure 6 is a cross-sectional view showing a third embodiment of the inductor component. The third embodiment differs from the first embodiment in the structure of the insulating layer. This different structure will be described below. Other structures are the same as in the first embodiment, and the same reference numerals are used as in the first embodiment, with their descriptions omitted.

[0178] As shown in Figure 6, the insulating layer 60C does not contain the bottom portion 62, the bottom-side first protrusion 67, and the bottom-side second protrusion 68 of the insulating layer 60 in the first embodiment. That is, the insulating layer 60C is composed of a top portion 61, a bottom portion 62, a first side portion 63, a second side portion 64, a top-side first protrusion 65, and a top-side second protrusion 66.

[0179] According to the above structure, similar to the first embodiment, it has a first protrusion 65 on the top surface side and a second protrusion 66 on the top surface side. Therefore, the contact area between the insulating layer 60 and the blank 10 can be increased by the first protrusion 65 and the second protrusion 66 on the top surface side. In addition, the first protrusion 65 and the second protrusion 66 on the top surface side can penetrate deep into the blank 10. As a result, the tightness of the bonding between the insulating layer 60C and the blank 10 is improved, and the reliability of the inductor component can be improved.

[0180] In addition, since the volume of the insulating layer 60C can be reduced, the volume of the magnetic layer can be increased, thereby improving the inductance.

[0181] The manufacturing method of the inductor component with the above structure will be described.

[0182] In FIG4H of the first embodiment, the substrate 70 and copper foil 80 are removed by grinding, but at this time, the first insulating layer is also removed. That is, the bottom part, the bottom-side first protrusion, and the bottom-side second protrusion of the insulating layer are removed.

[0183] Alternatively, the top surface portion, the first protrusion on the top surface side, and the second protrusion on the top surface side of the insulating layer in the first embodiment may not be provided, but a bottom surface portion, a first side surface portion, a second side surface portion, a first protrusion on the bottom surface side, and a second protrusion on the bottom surface side may be provided instead.

[0184] <Fourth Implementation>

[0185] Figure 7 is a top view showing a fourth embodiment of the inductor component. Figure 8 is a cross-sectional view (AA) of Figure 7. The main difference between the fourth embodiment and the first embodiment is the structure of the coil and the insulating layer. This difference in structure will be described below. The other structures are the same as those in the first embodiment, and the same reference numerals are used as in the first embodiment, with their descriptions omitted.

[0186] As shown in Figures 7 and 8, in the inductor component 1D, the coil 15D has a third inductor wiring 21D and a fourth inductor wiring 22D. The third inductor wiring 21D is positioned above the fourth inductor wiring 22D. The third inductor wiring 21D has 0.5 turns or less, corresponding to the "small-turn inductor wiring" as described in the claims. The fourth inductor wiring 22D has a spiral shape with more than one turn, corresponding to the "other inductor wiring" as described in the claims. Viewed from the first direction, the fourth inductor wiring 22D overlaps with at least a portion of the third inductor wiring 21D. The fourth inductor wiring 22D does not unnecessarily extend in a plane orthogonal to the first direction, thus increasing the volume of the blank 10.

[0187] The outer peripheral end 23b of the third inductor wiring 21D is connected to the first external terminal 41 via a first vertical wiring 51 on its upper side. The inner peripheral end 23a of the third inductor wiring 21D is connected to the inner peripheral end 24a of the fourth inductor wiring 22D via a via (not shown) on its lower side. The outer peripheral end 24b of the fourth inductor wiring 22D is connected to the second external terminal 42 via a second vertical wiring 52 on its upper side. With the above structure, the third inductor wiring 21D and the fourth inductor wiring 22D are connected in series and electrically connected to the first external terminal 41 and the second external terminal 42.

[0188] A coating film 50 is provided on the first main surface 10a of the blank 10. The coating film 50 is made of an insulating material. The coating film 50 exposes the end faces of the first and second external terminals 41 and 42. The coating film 50 can suppress short circuits between the first external terminal 41 and the second external terminal 42.

[0189] The third inductor wiring 21D and the fourth inductor wiring 22D are covered by an insulating layer 60D. The insulating layer 60D has a first insulating portion 61D covering the third inductor wiring 21D and a second insulating portion 62D covering the fourth inductor wiring 22D. A portion of the first insulating portion 61D exists between the third inductor wiring 21D and the fourth inductor wiring 22D in a first direction.

[0190] The first insulating portion 61D covers the third inductor wiring 21D and extends continuously along the extending direction of the third inductor wiring 21D. The first insulating portion 61D has: a first portion 61D1 covering the third inductor wiring 21D, and a second portion 61D2 not covering the third inductor wiring 21D.

[0191] As shown in FIG8, in the first cross section orthogonal to the extension direction of the third inductor wiring 21D, the first part 61D1 has the same features as in the first embodiment: a top part 61, a bottom part 62, a first side part 63, a second side part 64, a top side first protrusion 65, a top side second protrusion 66, a bottom side first protrusion 67, and a bottom side second protrusion 68.

[0192] In a second cross-section orthogonal to the extending direction of the second portion 61D2, the second portion 61D2 includes: a main body portion 90, a top portion portion 91, a bottom portion portion 92, a top-side first protrusion 95, a top-side second protrusion 96, a bottom-side first protrusion 97, and a bottom-side second protrusion 98. In this embodiment, the first cross-section and the second cross-section are the same cross-section.

[0193] The main body 90 is located at a position corresponding to the extension direction of the third inductor wiring 21D. The top surface 91 is located further in a first direction than the main body 90. The bottom surface 92 is located further in a second direction than the main body 90. A first protrusion 95 on the top surface protrudes from the top surface 91 in a fifth direction orthogonal to the first direction than the main body 90. A second protrusion 96 on the top surface protrudes from the top surface 91 in a sixth direction opposite to the fifth direction than the main body 90. A first protrusion 97 on the bottom surface protrudes from the bottom surface 92 in a fifth direction than the main body 90. A second protrusion 98 on the bottom surface protrudes from the bottom surface 92 in a sixth direction than the main body 90. The top surface 91 contacts the upper surface of the main body 90. The bottom surface 92 contacts the lower surface of the main body 90. In this embodiment, the fifth direction is the negative Y direction, the same as the third direction. The sixth direction is the Y direction, the same as the fourth direction.

[0194] According to the above structure, since a second part 61D2 is provided in addition to the first part 61D1, the contact area between the first insulating portion 61D of the insulating layer 60D and the blank 10 can be further increased through the second part 61D2. In addition, the first protrusions 95, 97 and the second protrusions 96, 98 of the second part 61D2 can penetrate into the blank 10. As a result, the tightness of the connection between the insulating layer 60D and the blank 10 is further improved, and the reliability of the inductor component 1D can be further improved.

[0195] Furthermore, by setting a dummy insulating layer such as the second part 61D2, when viewed from the first direction, the fourth inductor wiring 22D is staggered from a portion of the third inductor wiring 21D and stacked relative to each other. When viewed from the first direction, the fourth inductor wiring 22D can overlap not only with the first part 61D1 but also with the second part 61D2, thus ensuring the flatness of the third inductor wiring 21D and the fourth inductor wiring 22D.

[0196] As shown in Figure 8, the second insulating portion 62D contacts the bottom and side surfaces of the fourth inductor wiring 22D, but not the top surface of the fourth inductor wiring 22D. The bottom portion 62 and bottom portion 92 of the first insulating portion 61D contact the top surface of the fourth inductor wiring 22D. Like the first insulating portion 61D, the second insulating portion 62D has a first protrusion and a second protrusion on its bottom surface, but it may also lack these protrusions.

[0197] In the fourth embodiment, the second part has a top surface and a bottom surface, but it is sufficient to have at least one of the top surface and the bottom surface, and the first protrusion and the second protrusion protrude from the at least one of the bottom surfaces.

[0198] In the fourth embodiment, the first protrusion and the second protrusion of the second part extend in a horizontal direction, but may also be inclined in a first direction or a second direction.

[0199] In the fourth embodiment, the third inductor wiring is arranged above the fourth inductor wiring, but the third inductor wiring may also be arranged below the fourth inductor wiring.

[0200] In the fourth embodiment, the fourth inductor wiring, which is "other inductor wiring", has more than one turn, but only more than 0.5 turns.

[0201] (Manufacturing method)

[0202] Next, the manufacturing method of inductor component 1 will be described. Figures 9A to 9K correspond to section AA of Figure 7 (Figure 8).

[0203] As shown in Figure 9A, a substrate 70 is prepared. The substrate 70 is made of inorganic materials such as ceramics, glass, and silicon. A first insulating layer 71 is coated on the main surface of the substrate 70, and the first insulating layer 71 is cured.

[0204] As shown in Figure 9B, a seed layer (Ti / Cu, not shown) is formed on the first insulating layer 71 by a known method such as sputtering or vapor deposition. Then, a dry film resist (DFR) is attached in the same manner as in Figure 4B, and a prescribed pattern is formed on the DFR using photolithography.

[0205] Furthermore, power is supplied to the seed layer, and the fourth inductor wiring 22D and the first dummy wiring 81 are formed on the first insulating layer 71 using electroplating. Then, the DFR is stripped, and the seed layer is etched. As a result, a gap is formed between the fourth inductor wiring 22D and the first dummy wiring 81.

[0206] As shown in Figure 9C, a second insulating layer 72 is applied and cured onto the fourth inductor wiring 22D and the first dummy wiring 81. At this time, the second insulating layer 72 also fills the aforementioned gap. Then, a laser irradiates the second insulating layer 72 to form an opening, exposing the first dummy wiring 81. At this time, a portion of the second insulating layer 72 overlaps with the first dummy wiring 81. This overlapping portion of the second insulating layer 72 corresponds to the first protrusion on the bottom side and the second protrusion on the bottom side. Furthermore, similar to the first embodiment, an annular opening can also be formed in the second insulating layer 72 on the dummy wiring 81. This shortens the laser irradiation time.

[0207] Then, although not shown, an opening is formed in the second insulating layer 72 to expose a portion of the fourth inductor wiring 22D, and a seed layer is formed on the second insulating layer 72. The DFR is then reattached, and a predetermined pattern is formed on the DFR using photolithography. The predetermined pattern consists of through-holes corresponding to the locations on the fourth inductor wiring 22D where the third inductor wiring 21D and the second vertical wiring 52 are disposed. Electroplating is used to form via wiring 35 on the fourth inductor wiring 22D. The DFR is then stripped, and the seed layer is etched.

[0208] As shown in Figure 9D, a seed layer (Ti / Cu, not shown) is formed on the first dummy wiring 81 and the second insulating layer 72 by a known method such as sputtering or vapor deposition. Then, similarly to Figure 9B, a dry film resist (DFR) is attached, and a specified pattern is formed on the DFR using photolithography.

[0209] Furthermore, power is supplied to the seed layer, and a third inductor wiring 21D and a second dummy wiring 82 are formed on the second insulating layer 72 using electroplating. Then, the DFR is stripped, and the seed layer is etched. This creates a gap between the third inductor wiring 21D and the second dummy wiring 82.

[0210] As shown in Figure 9E, a third insulating layer 73 is applied and cured onto the third inductor wiring 21D and the second dummy wiring 82. At this time, the third insulating layer 73 also fills the aforementioned gaps. Then, a laser irradiates the third insulating layer 73 to form an opening, exposing the second dummy wiring 82. At this time, a portion of the third insulating layer 73 overlaps with the second dummy wiring 82. This overlapping portion of the third insulating layer 73 corresponds to the first protrusion on the top surface and the second protrusion on the top surface. Furthermore, the third insulating layer 73 on the second dummy wiring 82 can also similarly form an annular opening, which can shorten the laser irradiation time.

[0211] Then, although not shown, an opening is formed in the third insulating layer 73 to expose a portion of the third inductor wiring 21D, and a seed layer is formed on the third insulating layer 73. The DFR is then reattached, and a predetermined pattern is formed on the DFR using photolithography. The predetermined pattern consists of through-holes corresponding to the positions where the first vertical wiring 51 is disposed on the third inductor wiring 21D, and through-holes corresponding to the positions where the second vertical wiring 52 is disposed. The first vertical wiring 51 is formed on the third inductor wiring 21D using electroplating, and the second vertical wiring 52 is also formed. Then, the DFR is stripped, and the seed layer is etched.

[0212] Then, a DFR (Dual Residual Frame) is set to protect the first vertical wiring 51 and the second vertical wiring 52. Then, as shown in FIG9F, the DFR is etched off the first dummy wiring 81 and the second dummy wiring 82. Thus, a first insulating portion 61D including a first portion 61D1 and a second portion 61D2 is formed. That is, the top portion 61, bottom portion 62, first side portion 63, second side portion 64, top side first protrusion 65, top side second protrusion 66, bottom side first protrusion 67, and bottom side second protrusion 68 of the first portion 61D1 are formed. In addition, the main body portion 90, top portion 91, bottom portion 92, top side first protrusion 95, top side second protrusion 96, bottom side first protrusion 97, and bottom side second protrusion 98 of the second portion 61D2 are formed.

[0213] As shown in Figure 9G, a laser irradiates a portion of the first insulating layer 71 and a portion of the substrate 70 to form an opening. The opening is located at a position corresponding to the magnetic circuit of the coil.

[0214] As shown in Figure 9H, the magnetic sheet that will become the second magnetic layer 12 is pressed from above the main surface of the substrate 70 toward the third inductor wiring 21D and the fourth inductor wiring 22D, and the second magnetic layer 12 covers the third inductor wiring 21D, the fourth inductor wiring 22D, the first vertical wiring 51, and the second vertical wiring 52. Then, the upper surface of the second magnetic layer 12 is ground so that the end faces of the first vertical wiring 51 and the second vertical wiring 52 are exposed from the upper surface of the second magnetic layer 12.

[0215] Then, a coating film 50 is coated on the upper surface of the second magnetic layer 12. Furthermore, the coating film 50 is formed into a predetermined pattern using a photolithography method and then cured. The predetermined pattern has openings at positions corresponding to the first and second external terminals 41, 42. The first and second external terminals 41, 42 are formed at these openings.

[0216] As shown in Figure 9I, the substrate 70 is removed by grinding. At this time, a portion of the first insulating layer 71 can also be removed. This forms a second insulating portion 62D, and together with the first insulating portion 61D, forms an insulating layer 60D. Then, other magnetic sheets, forming the first magnetic layer 11, are pressed from below the fourth inductor wiring 22D toward the fourth inductor wiring 22D, covering the fourth inductor wiring 22D with the first magnetic layer 11. Then, the first magnetic layer 11 is ground to a predetermined thickness.

[0217] As shown in Figure 9J, the inductor component is monolithized by cutting line D. As shown in Figure 9K, inductor component 1D is manufactured.

[0218] <Fifth Implementation>

[0219] Figure 10 is a cross-sectional view showing a fifth embodiment of the inductor component. Figure 10 is a cross-sectional view corresponding to Figure 8. The fifth embodiment differs from the fourth embodiment in the structure of the insulating layer. This different structure will be described below. The other structures are the same as those in the fourth embodiment, and the same reference numerals are used as in the fourth embodiment, and their descriptions are omitted.

[0220] As shown in Figure 10, in the inductor component 1E, the insulating layer 60E has a first insulating portion 61E covering the third inductor wiring 21D and a second insulating portion 62E covering the fourth inductor wiring 22D. That is, the first insulating portion 61E corresponds to the first part 61D1 of the fourth embodiment and does not include the second part 61D2 of the fourth embodiment. The second insulating portion 62E has the same structure as the second insulating portion 62D of the fourth embodiment.

[0221] In the first direction, the second magnetic layer 12, located at the same position as the third inductor wiring 21D, overlaps with a portion of the fourth inductor wiring 22D when viewed from a direction orthogonal to the first direction. This allows for an increase in the volume of the second magnetic layer 12 (the magnetic circuit of the coil).

[0222] Furthermore, the second magnetic layer 12, which overlaps with a portion of the fourth inductor wiring 22D, is located in the first direction of the fourth inductor wiring 22D. Accordingly, the filling of the second magnetic layer 12 is easy during manufacturing.

[0223] Furthermore, in the first direction, at the same location as the wiring of the third inductor, a first magnetic layer may also be present, preferably overlapping a portion of the wiring of the fourth inductor when viewed from a direction orthogonal to the first direction. This allows for an increase in the volume of the first magnetic layer 11 (the magnetic circuit of the coil).

[0224] At this point, the first magnetic layer, preferably overlapping a portion of the fourth inductor wiring, is located in the second direction of the fourth inductor wiring. This facilitates the filling of the first magnetic layer during manufacturing.

[0225] <Sixth Implementation Method>

[0226] Figure 11 is a cross-sectional view showing a sixth embodiment of the inductor component. Figure 11 is a cross-sectional view corresponding to Figure 8. The sixth embodiment differs from the fourth embodiment in the structure of the coil and the insulating layer. This difference in structure will be described below. Other structures are the same as those in the fourth embodiment, and the same reference numerals are used as in the fourth embodiment, with their descriptions omitted.

[0227] As shown in Figure 11, in the inductor component 1F, the coil 15F has a fifth inductor wiring 21F and a sixth inductor wiring 21G stacked along a first direction. The fifth inductor wiring 21F is disposed above the sixth inductor wiring 21G. Both the fifth inductor wiring 21F and the sixth inductor wiring 21G have 0.5 turns or less, corresponding to the "small-turn inductor wiring" described in the claims. The fifth inductor wiring 21F and the sixth inductor wiring 21G are connected in series and electrically connected to the first external terminal 41 and the second external terminal 42.

[0228] The insulating layer 60F has a first insulating portion 61F covering the fifth inductor wiring 21F and a second insulating portion 62F covering the sixth inductor wiring 21G. That is, the first insulating portion 61F and the second insulating portion 62F are respectively equivalent to the first part 61D1 of the fourth embodiment, excluding the second part 61D2 of the fourth embodiment.

[0229] Preferably, there are protrusions of different lengths in all the first protrusions 65, 67 and the second protrusions 66, 68. Specifically, there are protrusions of different lengths in the first protrusions 65, 67 and the second protrusions 66, 68 of the first insulating portion 61F and the first protrusions 65, 67 and the second protrusions 66, 68 of the second insulating portion 62F.

[0230] Based on the above structure, by extending the length of a portion of the first or second protrusion, the adhesion between the insulating layer and the blank 10 can be further improved. Furthermore, by shortening the length of a portion of the first or second protrusion, the magnetic reluctance of the magnetic circuit can be reduced, thereby improving the efficiency of inductance acquisition.

[0231] Preferably, the closer the fifth inductor wiring 21F is to the first direction, the shorter the lengths of the first protrusions 65, 67 and the second protrusions 66, 68 are. Specifically, the lengths of the first protrusions 65, 67 and the second protrusions 66, 68 of the first insulating portion 61F are shorter than the lengths of the first protrusions 65, 67 and the second protrusions 66, 68 of the second insulating portion 62F.

[0232] According to the above structure, the closer the fifth inductor wiring 21F is to the first direction, the shorter the lengths of the first protrusions 65 and 67 and the second protrusions 66 and 68 are. Therefore, the closer it is to the first direction, the wider the magnetic circuit area of ​​the coil 15F. As a result, when filling the second magnetic layer 12 from the first direction side of the coil 15F in the second direction during manufacturing, it becomes easier to fill the second magnetic layer 12 into the coil 15F, the filling rate is increased, and the inductance can be improved.

[0233] Preferably, the coil 15F is formed by connecting the fifth inductor wiring 21F and the sixth inductor wiring 21G in series to form one turn. All the first protrusions 65, 67 and the second protrusions 66, 68 are located in either the inner magnetic circuit or the outer magnetic circuit of the coil 15F. Specifically, the first protrusions 65, 67 of the first insulating portion 61F and the second protrusions 66, 68 of the second insulating portion 62F are located in the inner magnetic circuit of the coil 15F. The second protrusions 66, 68 of the first insulating portion 61F and the first protrusions 65, 67 of the second insulating portion 62F are located in the outer magnetic circuit of the coil 15F.

[0234] Based on the above structure, the adhesion between the insulating layer 60F and the blank 10 can be further improved.

[0235] Preferably, the material of the second insulating portion 62F covering the sixth inductor wiring 21G of the first layer is different from the material of the first insulating portion 61F covering the fifth inductor wiring 21F of the second layer.

[0236] Based on the above structure, design freedom can be increased. For example, the material of the second insulating portion 62F is preferably selected with consideration of peel strength and stress from the substrate. On the other hand, the material of the first insulating portion 61F is preferably selected based on factors such as laser performance, photolithographic resolution, and coverage of step differences.

[0237] Furthermore, there may be three or more layers of small-turn inductor wiring along the first direction. Additionally, the coil may be formed by connecting multiple small-turn inductor wirings in series to create one or more turns. Furthermore, there may be n (n≥2) layers of small-turn inductor wiring along the first direction, where the material of the insulation layer covering the first layer of small-turn inductor wiring is different from the material of the insulation layer covering the m-th (2≤m≤n) layer of small-turn inductor wiring.

[0238] Furthermore, this disclosure is not limited to the embodiments described above, and design changes can be made without departing from the spirit of this disclosure. For example, the feature points of each of the first to sixth embodiments can be combined in various ways.

[0239] In the above embodiments, "inductor wiring" refers to wiring that imparts inductance to an inductor component by generating magnetic flux in a magnetic layer when current flows through it, and there are no particular limitations on its structure, shape, or material. In particular, it is not limited to straight lines or curves (spirals = two-dimensional curves) extending on a plane as in the embodiments described above, and various known wiring shapes such as zigzag wiring can be used.

Claims

1. An inductor component comprising: a blank, a coil disposed within the blank, and an insulating layer of a non-magnetic material covering at least a portion of the coil, the blank having a first magnetic layer and a second magnetic layer sequentially stacked along a first direction, the coil having a small-turn inductor wiring of 0.5 turns or less extending between the first magnetic layer and the second magnetic layer along a plane orthogonal to the first direction, and in a first cross-section orthogonal to the extension direction of the small-turn inductor wiring, the small-turn inductor wiring having: a top surface facing the first direction, a bottom surface facing a second direction opposite to the first direction, and a bottom surface facing... The insulating layer has a first side facing a third direction orthogonal to the first direction and a second side facing a fourth direction opposite to the third direction. The insulating layer also has: a portion of a top portion that is closer to the first direction than the top surface and a portion of a bottom portion that is closer to the second direction than the bottom surface; a first side portion that covers the first side; a second side portion that covers the second side; a first protrusion that protrudes further into the third direction from the at least one portion than the first side portion; and a second protrusion that protrudes further into the fourth direction from the at least one portion than the second side portion.

2. The inductor component according to claim 1, wherein, The small-turn inductor wiring, which has multiple layers along the first direction, has protrusions of different lengths in all of the first and second protrusions in the first cross-section.

3. The inductor component according to claim 1, wherein, In the first cross-section of the small-turn inductor wiring with multiple layers along the first direction, the lengths of the first protrusion and the second protrusion are shorter the closer the small-turn inductor wiring is to the first direction.

4. The inductor component according to claim 2, wherein, In the first cross-section of the small-turn inductor wiring with multiple layers along the first direction, the lengths of the first protrusion and the second protrusion are shorter the closer the small-turn inductor wiring is to the first direction.

5. The inductor component according to any one of claims 1 to 4, wherein, In the first cross section, at least one of the first protrusion and the second protrusion is inclined in the second direction.

6. The inductor component according to any one of claims 1 to 4, wherein, In the first cross section, at least one of the first protrusion and the second protrusion is inclined in the first direction.

7. The inductor component according to any one of claims 1 to 4, wherein, The coil has multiple layers of small-turn inductor wiring along the first direction, and the coil is formed by connecting the multiple small-turn inductor wirings in series to form one or more turns. In the first cross-section, all the first protrusions and the second protrusions are located in either the inner magnetic circuit or the outer magnetic circuit of the coil.

8. The inductor component according to any one of claims 1 to 4, wherein, In the first cross section described above, the length of the first protrusion is different from the length of the second protrusion described above.

9. The inductor component according to any one of claims 1 to 4, wherein, There are n layers of the aforementioned small-turn inductor wiring along the first direction, where n≥2. The material of the insulating layer covering the first layer of the aforementioned small-turn inductor wiring is different from the material of the insulating layer covering the m-th layer of the aforementioned small-turn inductor wiring, where 2≤m≤n.

10. The inductor component according to any one of claims 1 to 4, wherein, The first magnetic layer and the second magnetic layer contain magnetic powder, the contact surface between the second magnetic layer and the first magnetic layer contains the cut surface of the magnetic powder, and the contact surface between the first magnetic layer and the second magnetic layer contains the surface of the magnetic powder.

11. The inductor component according to any one of claims 1 to 4, wherein, The insulating layer covers the small-turn inductor wiring and extends continuously along the extension direction of the small-turn inductor wiring. The insulating layer has a first portion that covers the small-turn inductor wiring and a second portion that does not cover the small-turn inductor wiring. In a second cross-section orthogonal to the extension direction of the second portion, the second portion has: a main body portion located at a position corresponding to the extension direction of the small-turn inductor wiring; a portion located at least one of a top portion closer to the first direction than the main body portion and a bottom portion located closer to the second direction than the main body portion; a first protrusion protruding from the at least one portion in a fifth direction orthogonal to the first direction than the main body portion; and a second protrusion protruding from the at least one portion in a sixth direction opposite to the fifth direction than the main body portion.

12. The inductor component according to any one of claims 1 to 4, wherein, Other inductor wiring is present at a location where, when viewed from the first direction, it overlaps with at least a portion of the wiring of the small-turn inductor described above.

13. The inductor component according to claim 12, wherein, In the first direction, the first magnetic layer or the second magnetic layer, which is located at the same position as the small-turn inductor wiring, overlaps with a portion of the other inductor wiring when viewed from a direction orthogonal to the first direction.

14. The inductor component according to claim 13, wherein, The first magnetic layer or the second magnetic layer that overlaps with a portion of the wiring of the other inductors described above is a second magnetic layer located in the first direction of the wiring of the other inductors described above.

15. The inductor component according to claim 13, wherein, The first magnetic layer or the second magnetic layer that overlaps with a portion of the other inductor wiring is a first magnetic layer located in the second direction of the other inductor wiring.

16. A method for manufacturing an inductor component, comprising: a step of forming a small-turn inductor wiring of 0.5 turns or less, wherein, In a first cross section orthogonal to the extension direction, the aforementioned small-turn inductor wiring has: a top surface facing the first direction, a bottom surface facing the second direction opposite to the first direction, a first side surface facing the third direction orthogonal to the first direction, and a second side surface facing the fourth direction opposite to the third direction. The process of forming an insulating layer to have at least one of a top portion located in the first direction (more than the top surface) and a bottom portion located in the second direction (more than the bottom surface), a first side portion covering the first side, a second side portion covering the second side, a first protrusion protruding from the at least one portion in the third direction (more than the first side portion), and a second protrusion protruding from the at least one portion in the fourth direction (more than the second side portion); and a process of stacking a first magnetic layer and a second magnetic layer along the first direction to clamp the small-turn inductor wiring and the insulating layer to form a blank.

17. The method for manufacturing an inductor component according to claim 16, wherein, In the process of forming the wiring of the small-turn inductor, a dummy wiring is formed at a position that can be repeated with the first protrusion or the second protrusion when viewed from the first direction. After the process of forming the wiring of the small-turn inductor, a process of removing the dummy wiring is also performed. In the process of forming the blank, the first magnetic layer or the second magnetic layer is filled at the position where the dummy wiring has been removed.

Images