Inductor component

Abstract

This inductor component is provided with an element body, a second interlayer insulating layer (33), and an inductor wire (50). The element body has a first main surface and contains a magnetic material. The second interlayer insulating layer (33) extends parallel to the first main surface in the element body, and has a flat plate shape. The inductor wire (50) contacts a surface of the second interlayer insulating layer (33) that is parallel to the first main surface. In the direction orthogonal to the first main surface, the direction from the inductor wire (50) side toward the second interlayer insulating layer (33) side is defined as a first positive direction (X1), and the direction opposite to the first positive direction (X1) is defined as a first negative direction (X2). Of the outer surfaces of the second interlayer insulating layer (33), a surface facing a direction parallel to the first main surface is defined as an end surface (ED). In a specific cross section orthogonal to the center line of the inductor wire (50), the entire end surface (ED) is an inclined surface that faces the direction parallel to the first main surface and faces the first negative direction (X2) or an inclined surface that faces the direction parallel to the first main surface and faces the first positive direction (X1).

Description

Inductor Components

[0001] The present disclosure relates to inductor components.

[0002] The inductor component disclosed in Patent Document 1 includes an element body, a first interlayer insulating layer, an inter-wiring insulating layer, a second interlayer insulating layer, and a coil. The element body is rectangular. The element body contains a magnetic material. The first interlayer insulating layer is located inside the element body and extends parallel to a main surface of the element body. The inter-wiring insulating layer extends from the first interlayer insulating layer in a direction perpendicular to the main surface. In a cross-sectional view perpendicular to the main surface, multiple inter-wiring insulating layers are arranged at intervals. The second interlayer insulating layer is connected to the inter-wiring insulating layer on the opposite side of the inter-wiring insulating layer from the first interlayer insulating layer. The second interlayer insulating layer is parallel to the first interlayer insulating layer. The coil is located in a region defined by the first interlayer insulating layer, the inter-wiring insulating layer, and the second interlayer insulating layer.

[0003] Patent No. 6690386

[0004] In the invention described in Patent Document 1, a first interlayer insulating layer, an inter-wiring insulating layer, and a second interlayer insulating layer are located within the element body. If the volume of the inductor component is the same, the inclusion of more insulating layers may result in a corresponding reduction in the volume of the magnetic material in the element body.

[0005] In order to solve the above problem, one aspect of the present disclosure is an inductor component comprising: an element body having a main surface and containing a magnetic material; a flat interlayer insulating layer extending within the element body parallel to the main surface; and an inductor wiring in contact with a surface of the interlayer insulating layer parallel to the main surface; wherein, among directions orthogonal to the main surface, a direction from the inductor wiring side toward the interlayer insulating layer side is defined as a positive direction, and a direction opposite to the positive direction is defined as a negative direction; and a surface of the outer surface of the interlayer insulating layer facing a direction parallel to the main surface is defined as an end face; in a specific cross section orthogonal to the center line of the inductor wiring, the entire end face is an inclined surface facing a direction parallel to the main surface and the negative direction, or an inclined surface facing a direction parallel to the main surface and the positive direction.

[0006] According to the above configuration, an improvement in the inductance value of the inductor component can be expected.

[0007] FIG. 1 is a perspective view of an inductor component. FIG. 2 is a see-through side view of the inductor component. FIG. 3 is a see-through top view of the inductor component. FIG. 4 is a cross-sectional view of the inductor component taken along line 4-4 in FIG. 3. FIG. 5 is an enlarged cross-sectional view of a portion of a specific cross-section. FIG. 6 is an enlarged schematic view of the vicinity of the surface of a first interlayer insulating layer in a specific cross-section. FIG. 7 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 8 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 9 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 10 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 11 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 12 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 13 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 14 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 15 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 16 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 17 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 18 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 19 is an explanatory diagram of a method for manufacturing an inductor component. FIG. 20 is an explanatory diagram of a method for manufacturing an inductor component. Fig. 21 is an explanatory diagram of a manufacturing method of an inductor component. Fig. 22 is an explanatory diagram of a manufacturing method of an inductor component. Fig. 23 is an explanatory diagram of a manufacturing method of an inductor component. Fig. 24 is a cross-sectional view of an inductor component according to a modified example. Fig. 25 is an enlarged cross-sectional view of a part of a specific cross section of the inductor component according to a modified example.

[0008] An embodiment of an inductor component will be described below with reference to the drawings. Note that the drawings may show components enlarged to facilitate understanding. The dimensional ratios of the components may differ from those in the actual components or from those in other drawings.

[0009] <Overall Configuration> As shown in Fig. 1, the inductor component 10 has a generally rectangular parallelepiped shape. As shown in Fig. 2, the inductor component 10 includes an element body 11 and an inductor wiring 50.

[0010] As shown in Fig. 1, the element body 11 has six planar outer surfaces. Of these six outer surfaces, a specific one is designated as a first main surface 11A. Furthermore, a surface located opposite the first main surface 11A and parallel to the first main surface 11A is designated as a second main surface 11B. The outer shapes of the first main surface 11A and the second main surface 11B are both rectangular. In this embodiment, the first main surface 11A is the mounting surface that faces the substrate when the inductor component 10 is mounted on the substrate.

[0011] Here, an axis perpendicular to the first main surface 11A is defined as the first axis X. An axis perpendicular to the first axis X and parallel to a specific side of the first main surface 11A (in this embodiment, the long side of the first main surface 11A) is defined as the second axis Y. An axis perpendicular to the first axis X and the second axis Y is defined as the third axis Z. The direction along the first axis X in which the first main surface 11A faces is defined as the first positive direction X1, and the direction opposite to the first positive direction X1 is defined as the first negative direction X2. A specific direction along the second axis Y is defined as the second positive direction Y1, and the direction opposite to the second positive direction Y1 is defined as the second negative direction Y2. A specific direction along the third axis Z is defined as the third positive direction Z1, and the direction opposite to the third positive direction Z1 is defined as the third negative direction Z2.

[0012] As shown in FIG. 4 , the element body 11 includes, as magnetic layers 20, a first magnetic layer 21, a first interlayer magnetic layer 22, a second magnetic layer 23, a second interlayer magnetic layer 24, and a third magnetic layer 25, in that order from the first negative direction X2. While FIG. 4 shows the boundaries between the magnetic layers 20 as virtual double-dashed lines, it may not be possible to clearly see the boundaries between the magnetic layers 20. The magnetic layers 20 are made of an organic resin containing metal magnetic powder. That is, the element body 11 contains a magnetic material. In this embodiment, the metal magnetic powder is a metal magnetic powder made of an Fe-based alloy or an amorphous alloy. More specifically, the metal magnetic powder is an FeSiCr-based metal powder containing iron. The metal magnetic powder is not limited to an FeSiCr-based magnetic powder, but may also be, for example, an FeCo-based, FeSiAr-based, iron oxide-based, or a combination thereof. The organic resin may be an epoxy resin, an imide resin, a liquid crystal polymer resin, an acrylic resin, a phenol resin, or a combination thereof. The organic resin may contain an inorganic filler in addition to the above materials.

[0013] As shown in Fig. 2, the inductor wiring 50 is located inside the element body 11. As shown in Fig. 4, the inductor wiring 50 is located at the same location as the second magnetic layer 23 in a direction perpendicular to the first main surface 11A. The material of the inductor wiring 50 is a conductive material. In this embodiment, the composition of the inductor wiring 50 is, for example, a copper ratio of 99 wt% or more and a sulfur ratio of 0.1 wt% or more and 1.0 wt% or less. Note that the inductor wiring 50 is not limited to a conductor whose main component is copper, and may also be a conductor whose main components are Ag, Al, and Au.

[0014] As shown in FIG. 3 , the inductor wiring 50 extends in a spiral shape parallel to the first main surface 11A. That is, the inductor wiring 50 is linear. As shown in FIG. 4 , the inductor wiring 50 includes a seed layer 51A. The seed layer 51A constitutes a part of the surface of the inductor wiring 50 on the first negative direction X2 side. The seed layer 51A is made of copper. As will be described later, electrolytic copper plating is performed on the seed layer 51A, whereby copper grows on the seed layer 51A, forming the entire inductor wiring 50. Note that, in the process of promoting the growth of the copper plating, the surface of the inductor wiring 50 on the first positive direction X1 side may become a curved surface that is convex toward the first positive direction X1 side.

[0015] As shown in FIG. 3 , the inductor wiring 50 has a pair of pad portions 51P and a wiring main body 51L. The pair of pad portions 51P are located at both ends of the inductor wiring 50. One of the pair of pad portions 51P is referred to as an inner pad portion 51PA. The remaining one of the pair of pad portions 51P is referred to as an outer pad portion 51PB. When viewed in the first negative direction X2, the inner pad portion 51PA is located on the second positive direction Y1 side with respect to the geometric center of the element body 11. When viewed in the first negative direction X2, the inner pad portion 51PA has a substantially circular shape. When viewed in the first negative direction X2, the outer pad portion 51PB is located on the second negative direction Y2 side with respect to the geometric center of the element body 11. When viewed in the first negative direction X2, the outer pad portion 51PB has a substantially rectangular shape.

[0016] The wiring body 51L connects a pair of pad portions 51P. Specifically, when the element body 11 is viewed in the first negative direction X2, the wiring body 51L extends counterclockwise from the inner pad portion 51PA toward the outer pad portion 51PB such that the diameter increases as the number of turns increases. The number of turns of the inductor wiring 50 is 2.5 turns.

[0017] The number of turns of the inductor wiring 50 is determined based on a virtual vector. The starting point of the virtual vector is located on the center line of the inductor wiring 50. When the virtual vector is moved from a state in which the starting point is located at a first end of the center line to a second end of the center line as viewed in the first negative direction X2, the number of turns is determined to be 1.0 turn when the angle by which the direction of the virtual vector rotates is 360 degrees. However, when the direction of the virtual vector involves multiple windings, the number of turns increases when the windings are consecutive in the same direction.

[0018] The center line of the inductor wiring 50 is determined as follows: When viewed in the first negative direction X2, the shortest line segment that can be drawn from any point on the edge of the inductor wiring 50 to the opposite edge is identified. The line connecting the points that pass through the centers of this identified line segment is defined as the center line of the inductor wiring 50 when viewed in the first negative direction X2.

[0019] As shown in FIG. 4 , the inductor component 10 includes insulating layers 30, which are a first interlayer insulating layer 31, an inter-wiring insulating layer 32, and a second interlayer insulating layer 33. The first interlayer insulating layer 31 is flat. The first interlayer insulating layer 31 extends parallel to the first main surface 11A within the element body 11. The first interlayer insulating layer 31 is in contact with the surface of the first magnetic layer 21 on the first positive direction X1 side. The first interlayer insulating layer 31 is also in contact with the surface of the inductor wiring 50 on the first negative direction X2 side. In other words, the inductor wiring 50 extends on the first positive direction X1 side relative to the first interlayer insulating layer 31. Therefore, the first interlayer insulating layer 31 is located at the same location as the first interlayer magnetic layer 22 in a direction perpendicular to the first main surface 11A.

[0020] The second interlayer insulating layer 33 has a flat plate shape. The second interlayer insulating layer 33 extends parallel to the first main surface 11A within the element body 11. The second interlayer insulating layer 33 is in contact with the surface of the inductor wiring 50 on the first positive direction X1 side. That is, the inductor wiring 50 is in contact with the surface of the second interlayer insulating layer 33 that is parallel to the first main surface 11A. A partial gap may occur between the inductor wiring 50 and the second interlayer insulating layer 33. The first positive direction X1 is a direction perpendicular to the first main surface 11A that extends from the inductor wiring 50 side toward the second interlayer insulating layer 33 side. The second interlayer insulating layer 33 is in contact with the surface of the third magnetic layer 25 on the first negative direction X2 side. Therefore, the second interlayer insulating layer 33 is located in the same position as the second interlayer magnetic layer 24 in the direction perpendicular to the first main surface 11A.

[0021] When a surface of the inductor wiring 50 facing a direction parallel to the first main surface 11A is defined as a side surface, the inter-wiring insulating layer 32 covers the side surface of the inductor wiring 50. Therefore, the inter-wiring insulating layer 32 has a portion adjacent to the inductor wiring 50 in a direction parallel to the first main surface 11A. In this embodiment, the entire inter-wiring insulating layer 32 is adjacent to the inductor wiring 50 in a direction parallel to the first main surface 11A. The inter-wiring insulating layer 32 extends from the second inter-layer insulating layer 33 in a direction perpendicular to the first main surface 11A, i.e., in the first negative direction X2. In other words, the inter-wiring insulating layer 32 extends from the first inter-layer insulating layer 31 in the first positive direction X1. Furthermore, in a specific cross section perpendicular to the center line of the inductor wiring 50, the inter-wiring insulating layer 32 is present in a plurality of discontinuous locations in a direction along the first main surface 11A. 4, for example, the inter-wiring insulating layer 32 is present in seven discontinuous locations along the first main surface 11A. The specific cross section shown in FIG. 4 is a plane that passes through the geometric center of the element body 11 and is perpendicular to the second axis Y.

[0022] Here, among the locations of the inter-wiring insulating layer 32 in the specific cross section, the locations where the surface parallel to the first main surface 11A is in contact with the element body 11 are referred to as outer insulating layers 32A. Furthermore, among the locations of the inter-wiring insulating layer 32 in the specific cross section, the locations where the surface parallel to the first main surface 11A is not in contact with the element body 11 are referred to as inner insulating layers 32B. For example, in the specific cross section shown in FIG. 4 , there are four outer insulating layers 32A. Furthermore, there are three inner insulating layers 32B in the specific cross section. Specifically, in the specific cross section, two outer insulating layers 32A are located on the third positive direction Z1 side of the geometric center of the element body 11, and two inner insulating layers 32B are located between the outer insulating layers 32A. Furthermore, the inductor wiring 50 is located between these inter-wiring insulating layers 32. Furthermore, two outer insulating layers 32A are located on the third negative direction Z2 side of the geometric center of the element body 11, and one inner insulating layer 32B is located between the outer insulating layers 32A. The inductor wiring 50 is located between these inter-wiring insulating layers 32. That is, the inductor wiring 50 is located within a region defined by the inter-wiring insulating layers 32.

[0023] 2 , the inductor component 10 includes two pillar wirings 40 and two external electrodes 60. Each pillar wiring 40 extends in a direction intersecting the first main surface 11A. In this embodiment, each pillar wiring 40 extends in a direction perpendicular to the first main surface 11A. Each pillar wiring 40 is located on the first positive direction X1 side with respect to the inductor wiring 50. Each pillar wiring 40 is electrically connected to the inductor wiring 50.

[0024] Specifically, the first columnar wiring 41, which is one of the two columnar wirings 40, includes a first via 41A and a first escape wiring 41B. The material of the first columnar wiring 41 is the same as the material of the inductor wiring 50. The first via 41A has a substantially cylindrical shape. The first via 41A penetrates the second interlayer insulating layer 33. That is, the first columnar wiring 41 penetrates the second interlayer insulating layer 33. As a result, the first via 41A is located at the same position as the second interlayer insulating layer 33 and the second interlayer magnetic layer 24 in a direction perpendicular to the first main surface 11A. The surface of the first via 41A facing the first negative direction X2 is connected to the inner pad portion 51PA of the inductor wiring 50.

[0025] As shown in Fig. 3, the first escape routing 41B has a substantially cylindrical shape. As shown in Fig. 2, the diameter of the first escape routing 41B is slightly larger than the diameter of the first via 41A. The surface of the first escape routing 41B facing the first negative direction X2 is connected to the first via 41A. Therefore, the first escape routing 41B is located at the same position as the third magnetic layer 25 in a direction perpendicular to the first main surface 11A. The surface of the first escape routing 41B facing the first positive direction X1 is exposed from the first main surface 11A.

[0026] As shown in FIG. 2 , the second columnar wiring 42, which is the other of the two columnar wirings 40, includes a second via 42A and a second lead wiring 42B. The material of the second columnar wiring 42 is the same as the material of the inductor wiring 50. The second columnar wiring 42 is located on the second negative direction Y2 side with respect to the first columnar wiring 41. The second via 42A has a substantially rectangular prism shape. The second via 42A penetrates the second interlayer insulating layer 33. That is, the second columnar wiring 42 penetrates the second interlayer insulating layer 33. As a result, the second via 42A is located at the same position as the second interlayer insulating layer 33 and the second interlayer magnetic layer 24 in the direction perpendicular to the first main surface 11A. The surface of the second via 42A facing the first negative direction X2 is connected to the outer pad portion 51PB of the inductor wiring 50.

[0027] As shown in Fig. 3, the second escape wiring 42B has a substantially rectangular prism shape. As shown in Fig. 2, the dimensions of each side of the second escape wiring 42B are slightly larger than the dimensions of each side of the second via 42A. The surface of the second escape wiring 42B facing the first negative direction X2 is connected to the second via 42A. Therefore, the second escape wiring 42B is located at the same position as the third magnetic layer 25 in a direction perpendicular to the first main surface 11A. The surface of the second escape wiring 42B facing the first positive direction X1 is exposed from the first main surface 11A.

[0028] 1 , each external electrode 60 is exposed from the element body 11. Specifically, each external electrode 60 is located on the first main surface 11A of the element body 11. In other words, each external electrode 60 covers a portion of the outer surface of the element body 11.

[0029] 2 , a first external electrode 61, which is one of the two external electrodes 60, is located on the first main surface 11A on the second positive direction Y1 side with respect to the geometric center of the first main surface 11A. The first external electrode 61 is in contact with a surface of the first escape wiring 41B facing the first positive direction X1. A second external electrode 62, which is the other of the two external electrodes 60, is located on the first main surface 11A on the second negative direction Y2 side with respect to the geometric center of the first main surface 11A. The second external electrode 62 is in contact with a surface of the second escape wiring 42B facing the first positive direction X1.

[0030] The inductor component 10 includes a solder resist 70. The solder resist 70 covers the surface of the element body 11 facing the first positive direction X1, excluding the two external electrodes 60. In other words, the first main surface 11A of the element body 11 is covered by the external electrodes 60 and the solder resist 70 and is not exposed. The solder resist 70 has higher insulating properties than the element body 11.

[0031] <Materials of Insulating Layers> The following describes the materials of the first interlayer insulating layer 31 and the inter-wiring insulating layer 32. The material of the second interlayer insulating layer 33 is the same as that of the first interlayer insulating layer 31. Therefore, only the material of the first interlayer insulating layer 31 will be described.

[0032] As shown in Figure 6, the first interlayer insulating layer 31 contains a photocurable synthetic resin SR and a plurality of fillers FL dispersed within the synthetic resin SR. Dispersed here means that the fillers FL are randomly positioned within the synthetic resin SR. Therefore, even if some of the fillers FL are aggregated, the fillers FL are said to be dispersed as long as the overall arrangement of the fillers FL is random. Note that in Figure 6, only some of the fillers FL are labeled with reference numerals.

[0033] In this embodiment, the synthetic resin SR is an insulating resin. Specifically, the synthetic resin SR is a polyimide resin. This synthetic resin SR is a photocurable resin that is cured by ultraviolet light. The volume fraction of the synthetic resin SR in the first interlayer insulating layer 31 is 40 Vol% or more and 70 Vol% or less. The volume fraction of the synthetic resin SR in the first interlayer insulating layer 31 is calculated, for example, as follows: First, a cross section of the first interlayer insulating layer 31 with a side length of 500 nm is observed using a scanning electron microscope (SEM). Within this area, the area without filler FL, i.e., the total area of ​​the synthetic resin SR, is calculated using image processing. Then, the area ratio is calculated from the area ratio of the total area of ​​the synthetic resin SR to the observed area. This process is repeated three or more times on different cross sections of the first interlayer insulating layer 31, and the area ratio of each area is calculated. The calculated area ratios are then averaged, and this calculation result is used as the volume fraction.

[0034] The filler FL is a non-magnetic inorganic insulating compound. In this embodiment, the filler FL is silica. That is, in this embodiment, the plurality of fillers FL are a non-magnetic inorganic oxide.

[0035] Furthermore, the inter-wiring insulating layer 32 contains an insulating synthetic resin SR but does not contain the above-mentioned filler FL. In this embodiment, the material of the synthetic resin SR of the inter-wiring insulating layer 32 is the same as the material of the synthetic resin SR of the first interlayer insulating layer 31. That is, the material of the synthetic resin SR of the inter-wiring insulating layer 32 is a polyimide resin.

[0036] <Regarding the Shape of the Second Interlayer Insulating Layer> As shown in FIG. 5 , the outer surface of the second interlayer insulating layer 33 that faces a direction parallel to the first main surface 11A is referred to as the end surface ED. In this embodiment, the entire end surface ED is planar. As shown in FIG. 4 , in a specific cross section, there are two end surfaces ED per second interlayer insulating layer 33. As shown in FIG. 5 , in the specific cross section, the entire end surface ED is an inclined surface that faces a direction parallel to the first main surface 11A and the first negative direction X2. In the example shown in FIG. 5 , the end surface ED faces the third positive direction Z1 and the first negative direction X2. In this way, the end surface ED of the second interlayer insulating layer 33 is an inclined surface with respect to a virtual axis perpendicular to the first main surface 11A. In FIG. 5 , the virtual axis coincides with the boundary BD. In addition, as long as the entire end face ED is an inclined surface facing the above-mentioned direction in a particular cross section perpendicular to the center line of the inductor wiring 50, the entire end face ED does not have to be an inclined surface facing the above-mentioned direction in a different cross section.

[0037] Here, in a specific cross section, the outermost edge of the end face ED of the second interlayer insulating layer 33 is defined as the outermost edge EO. In this embodiment, the outermost edge EO is the outer edge of the surface of the second interlayer insulating layer 33 facing the first positive direction X1. In other words, the outermost edge EO is the edge of the end face ED on the first positive direction X1 side. The outer edge of the surface of the second interlayer insulating layer 33 facing the first negative direction X2 is located inside the outermost edge EO. In other words, the entire end face ED of the second interlayer insulating layer 33 has a shape recessed with respect to the outermost edge EO.

[0038] 3, when the inductor component 10 is seen through in a direction perpendicular to the first main surface 11A, the outermost edge EO of the end face ED is located on the boundary BD between the element body 11 and the outer insulating layer 32A. That is, as shown in FIG. 5, in a specific cross section, the outermost edge EO of the end face ED of the second interlayer insulating layer 33 is located on an imaginary line VL extending the boundary BD between the element body 11 and the outer insulating layer 32A in a direction perpendicular to the first main surface 11A. In addition, in this embodiment, the end of the end face ED of the second interlayer insulating layer 33 on the first negative direction X2 side is located on the surface of the outer insulating layer 32A on the first positive direction X1 side.

[0039] <Manufacturing Method> Next, a method for manufacturing the inductor component 10 will be described. First, a base preparation step is performed, as shown in FIG. 7 . Specifically, a plate-shaped base member 101 is prepared. The material of the base member 101 is ceramic. When viewed in the first negative direction X2, the base member 101 has a rectangular shape. The dimensions of each side of the base member 101 are such that multiple inductor components 10 can be accommodated. Next, a dummy insulating layer 102 is applied to the first positive direction X1 side of the base member 101, i.e., the entire upper surface. Note that in FIG. 7 , the dummy insulating layer 102 is illustrated by a thick line.

[0040] Next, as shown in FIG. 8 , a first insulating layer processing step is performed to form a first interlayer insulating layer 31. The first interlayer insulating layer 31 is formed on the surface of the base member 101 facing the first positive direction X1. Specifically, the first interlayer insulating layer 31 is patterned. The patterning is performed over an area slightly larger than the area in which the inductor wiring 50 is to be disposed. Specifically, the first interlayer insulating layer 31 containing a filler FL and a photocurable synthetic resin SR is formed by photolithography. That is, the synthetic resin SR contained in the first interlayer insulating layer 31 is cured by ultraviolet light.

[0041] 9, a seed formation step is performed to form a seed layer 51A. Specifically, a copper seed portion 103 is formed by sputtering on the surfaces of the first interlayer insulating layer 31 and the dummy insulating layer 102 on the first positive direction X1 side.

[0042] 10, a photo-curable resist 104 is laminated on the upper surface of the seed portion 103. Then, only the area of ​​the upper surface of the seed portion 103 where the seed layer 51A of the inductor wiring 50 is to be formed is exposed to light. The exposed areas of the resist 104 are hardened. These hardened areas are formed as the covering portion 105. Thereafter, the unhardened parts of the resist 104, i.e., the parts other than the covering portion 105, are removed.

[0043] Next, as shown in Fig. 11, the seed portion 103 is etched. As a result, the seed portion 103 exposed from the covering portion 105 is removed. Then, as shown in Fig. 12, the covering portion 105 is wet-etched using a chemical. As a result, the covering portion 105 is peeled off. As a result, a seed layer 51A is formed.

[0044] 13, a second insulating layer processing step is performed to form the inter-wiring insulating layer 32. Specifically, first, a photo-curable permanent resist 106 is laminated on the surfaces of the dummy insulating layer 102, the seed layer 51A, and the first interlayer insulating layer 31 on the first positive direction X1 side. Next, the area where the inter-wiring insulating layer 32 is to be formed, i.e., the areas located on both sides of the seed layer 51A, are exposed to light.

[0045] 14, unhardened portions of the permanent resist 106 are peeled off and removed using a chemical solution, thereby forming the inter-wiring insulating layer 32. The permanent resist 106 is made of only synthetic resin SR.

[0046] 15 , a first wiring formation step is performed to form the inductor wiring 50. Specifically, electrolytic copper plating is performed to grow copper from the exposed portion of the seed layer 51A on the surface of the first interlayer insulating layer 31 on the first positive direction X1 side. This forms the entire inductor wiring 50. Note that, in the process of promoting the growth of the copper plating, the surface of the inductor wiring 50 on the first positive direction X1 side may become a curved surface that is convex toward the first positive direction X1 side.

[0047] Next, as shown in FIG. 16 , a third insulating layer processing step is performed to form a second interlayer insulating layer 33. The second interlayer insulating layer 33 is formed in the area of ​​the first positive direction X1 side surfaces of the inductor wiring 50 and the interlayer insulating layer 32, excluding the areas where the first via 41A and the second via 42A are to be formed. The second interlayer insulating layer 33 is formed in this area using the same photolithography method as that used to form the first interlayer insulating layer 31. Note that when forming the second interlayer insulating layer 33 using photolithography, the exposure amount is adjusted so that the first positive direction X1 side of the second interlayer insulating layer 33 to be formed has a greater amount of exposure than the first negative direction X2 side. For example, ultraviolet light is irradiated onto the uncured second interlayer insulating layer 33 from the first positive direction X1 side. During this process, the ultraviolet light is blocked or scattered by the filler FL as it travels through the second interlayer insulating layer 33, gradually attenuating its intensity. Therefore, the above-described adjustment of the exposure dose is possible by irradiating the second interlayer insulating layer 33 with ultraviolet light at an intensity such that only a small amount of light reaches the end of the second interlayer insulating layer 33 on the first negative direction X2 side. The above-described adjustment of the exposure dose can also be achieved by, for example, adjusting the irradiation angle of the ultraviolet light. By adjusting the exposure dose in this manner, curing is accelerated on the first positive direction X1 side more than on the first negative direction X2 side, and the entire end surface ED of the second interlayer insulating layer 33 is formed at an angle facing the first negative direction X2 side. Furthermore, when viewed in the first negative direction X2, the outermost edge EO of the end surface ED of the second interlayer insulating layer 33 coincides with the outermost edge of the inter-wiring insulating layer 32. Note that only some of the outermost edges EO are labeled in FIG. 16 .

[0048] Next, as shown in FIG. 17 , a second wiring formation process is performed to form the pillar wiring 40. The area in which the pillar wiring 40 is formed includes the area in which the inductor wiring 50 is exposed from the second interlayer insulating layer 33. First, a pillar-shaped seed layer 107 is formed in the above-mentioned area in the same manner as in the seed formation process described above. Note that the pillar-shaped seed layer 107 is not shown in FIGS. 2 and 3 . Then, using photolithography in the same manner as in the first insulating layer processing process, a resist is exposed to light in the area outside the above-mentioned area. Then, a process similar to the first wiring formation process is performed to form the pillar wiring 40 by copper plating. Thereafter, the resist is removed. As a result, a first pillar wiring 41 and a second pillar wiring 42 are formed.

[0049] 18 , a first magnetic body forming process is performed to form the magnetic layers 20 other than the first magnetic layer 21. First, a resin containing magnetic powder, which is the material for the magnetic layer 20, is applied to the dummy insulating layer 102 on the side facing the first positive direction X1. At this time, the resin containing magnetic powder is applied so as to cover the surface of each columnar wiring 40 facing the first positive direction X1. Next, the resin containing magnetic powder is hardened by pressing, thereby forming the first interlayer magnetic layer 22, the second interlayer magnetic layer 23, the second interlayer magnetic layer 24, and the third magnetic layer 25 on the surface facing the first positive direction X1 of the dummy insulating layer 102.

[0050] Then, the portion of the third magnetic layer 25 on the first positive direction X1 side is removed until the surface of each columnar wiring 40 on the first positive direction X1 side is exposed. In FIG. 18 , the first interlayer magnetic layer 22, the second magnetic layer 23, the second interlayer magnetic layer 24, and the third magnetic layer 25 are indistinguishably illustrated as the magnetic layer 20.

[0051] 19, a base member cutting step is performed. Specifically, the base member 101 and the dummy insulating layer 102 are all removed by cutting. Note that as a result of all of the base member 101 and the dummy insulating layer 102 being cut, a portion of the first interlayer insulating layer 31 on the first negative direction X2 side may be removed, but the inductor wiring 50 is not removed.

[0052] Next, as shown in FIG. 20 , a second magnetic body forming process is performed to form the first magnetic layer 21. Specifically, first, a resin containing magnetic powder, which is the material of the first magnetic layer 21, is applied to the surfaces of the first interlayer insulating layer 31 and the first interlayer magnetic layer 22 on the first negative direction X2 side. Then, the resin containing magnetic powder is hardened by pressing. After that, the portion of the resin on the first negative direction X2 side is removed. For example, the portion of the resin on the first negative direction X2 side is removed so that the dimension of the inductor component 10 in the direction along the first axis X becomes a desired value. As a result, the first magnetic layer 21 is formed on the surfaces of the first interlayer insulating layer 31 and the first interlayer magnetic layer 22 on the first negative direction X2 side. Note that in FIG. 20 , the first magnetic layer 21, the first interlayer magnetic layer 22, the second magnetic layer 23, the second interlayer magnetic layer 24, and the third magnetic layer 25 are all illustrated as the magnetic layer 20 without distinction.

[0053] 21 , a main surface processing step is performed to form a solder resist 70. Specifically, an insulator is patterned by photolithography on portions of the surface of the third magnetic layer 25 on the first positive direction X1 side and the surfaces of each columnar wiring 40 on the first positive direction X1 side where the external electrodes 60 are not to be formed. This forms the solder resist 70.

[0054] Next, as shown in FIG. 22 , an electrode processing step is performed to form the external electrodes 60. The external electrodes 60 are formed in the areas of the surface of the third magnetic layer 25 facing the first positive direction X1 and the surfaces of each columnar wiring 40 facing the first positive direction X1 that are not covered by the solder resist 70. Copper, nickel, and gold are electrolessly plated in these areas. As a result, a first external electrode 61 and a second external electrode 62 are formed. Note that in FIG. 22 , the copper, nickel, and gold layers are not distinguished from one another. Also, as shown in FIG. 22 , a portion of the external electrode 60 may cover a portion of the surface of the solder resist 70 facing the first positive direction X1. Next, as shown in FIG. 23 , a singulation step is performed. Specifically, the inductor component 10 is singulated by dicing along the break lines DL. This allows the inductor component 10 to be obtained.

[0055] <Effects of this Embodiment> (1) In the above embodiment, the entire end face ED is an inclined surface that is parallel to the first main surface 11A and faces the first negative direction X2. That is, the end face ED of the second interlayer insulating layer 33 is recessed relative to the outermost edge EO of the surface of the second interlayer insulating layer 33 facing the first positive direction X1. Since the element body 11 can be present in this recessed portion of the end face ED, the volume of the element body 11 can be increased accordingly. That is, with the above configuration, when the inductor component 10 is viewed through in a direction perpendicular to the first main surface 11A, the volume of the magnetic material can be increased compared to when the entire end face ED of the second interlayer insulating layer 33 is located on the boundary BD. As a result, an improvement in the inductance value of the inductor component 10 can be expected.

[0056] (2) In the above embodiment, the columnar wiring 40 penetrates the second interlayer insulating layer 33 in a direction intersecting the first main surface 11A and is connected to the inductor wiring 50. In other words, the distance between the second interlayer insulating layer 33, which has an end face ED that is an inclined surface, and the columnar wiring 40 is short. In the element body 11, in the vicinity of the columnar wiring 40 that is connected to the inductor wiring 50, magnetic flux may concentrate when a current flows. In such a location where magnetic flux is likely to concentrate, the shape of the end face ED described above ensures a volume of magnetic material, making it less likely for magnetic flux saturation to occur in the inductor component 10.

[0057] (3) In the above embodiment, in the specific cross section, the outermost edge EO of the end face ED of the second interlayer insulating layer 33 is located on an imaginary line VL extending the boundary BD between the element body 11 and the outer insulating layer 32A in a direction perpendicular to the first main surface 11A. That is, when the inductor component 10 is seen through in a direction perpendicular to the first main surface 11A, the second interlayer insulating layer 33 has a minimum size that can cover the inter-wiring insulating layer 32 and the first interlayer insulating layer 31. The volume of the element body 11 can be increased relative to this minimum size of the second interlayer insulating layer 33 by the configuration of the end face ED described above, and therefore the proportion of the element body 11 occupied can be increased.

[0058] (4) In the above embodiment, the second interlayer insulating layer 33 includes a photocurable synthetic resin SR and a plurality of fillers FL dispersed within the synthetic resin SR. In this configuration, when the second interlayer insulating layer 33 is formed, the fillers FL block or scatter light, making it difficult for the synthetic resin SR to harden on the side opposite to the side where light is irradiated. Therefore, the side where hardening is accelerated tends to have larger dimensions in the planar direction than the side where hardening is not accelerated. This configuration is therefore suitable for forming the end face ED as an inclined surface.

[0059] <Modifications> The above embodiment and the following modifications can be implemented in combination with each other within the scope of technical compatibility.

[0060] In the above embodiment, the inductor component 10 does not necessarily have to have the external electrode 60. In this case, the portion of the columnar wiring 40 exposed from the first main surface 11A may be used as an electrode.

[0061] In the above embodiment, the columnar wirings 40 do not necessarily extend in a direction perpendicular to the first main surface 11A, but may extend in a direction intersecting the first main surface 11A. In the above embodiment, the columnar wirings 40 may be located on the first negative direction X2 side with respect to the inductor wiring 50. Similarly, the external electrode 60 may be exposed from the second main surface 11B. In other words, the mounting surface of the inductor component 10 may be the second main surface 11B.

[0062] In the above embodiment, the shape of each of the columnar wirings 40 when viewed in a direction perpendicular to the first main surface 11A is not limited to the example of the above embodiment. For example, the shape of each of the columnar wirings 40 when viewed in a direction perpendicular to the first main surface 11A may all be the same.

[0063] In the above embodiment, the number of turns and the shape of the inductor wiring 50 are not limited to those in the above embodiment. For example, the inductor wiring 50 may be linear with no turns.

[0064] In the above embodiments, a portion of the inductor wiring 50 may not be covered by the insulating layer 30 and may be in contact with the magnetic layer 20. In the above embodiments, the inductor component 10 may include multiple inductor wirings 50. For example, assume that the inductor wiring 50 in the above embodiments is the first inductor wiring 50, the inter-wiring insulating layer 32 is the first inter-wiring insulating layer 32, and the outer insulating layer 32A is the first outer insulating layer 32A. In the example shown in FIG. 24 , the inductor component 10 further includes a second inductor wiring 52, a second inter-wiring insulating layer 34, and a third inter-layer insulating layer 35. In the example shown in FIG. 24 , the second inter-wiring insulating layer 34 extends from the second inter-layer insulating layer 33 in the first positive direction X1. The second inductor wiring 52 extends on the first positive direction X1 side with respect to the second inter-layer insulating layer 33 within a region defined by the second inter-wiring insulating layer 34. The third interlayer insulating layer 35 extends on the surfaces of the second inductor wiring 52 and the second interlayer insulating layer 34 on the first positive direction X1 side. That is, the second inductor wiring 52 is in contact with a surface of the third interlayer insulating layer 35 that is parallel to the first main surface 11A. The third interlayer insulating layer 35 is flat. The third interlayer insulating layer 35 extends parallel to the first main surface 11A. In this example, the first positive direction X1 is the direction from the second inductor wiring 52 side toward the third interlayer insulating layer 35. In the example shown in FIG. 24 , the columnar wiring 40 is connected to the second inductor wiring 52.

[0065] 24 , similar to the first inter-wiring insulating layer 32, the second inter-wiring insulating layer 34 is present in seven discontinuous locations in the direction along the first main surface 11A in the specific cross section. Note that FIG. 24 illustrates four of the seven second inter-wiring insulating layers 34. The first inter-wiring insulating layer 32 is also illustrated in this regard. Of the locations of the second inter-wiring insulating layer 34 in the specific cross section, the location where the surface facing a direction parallel to the first main surface 11A is in contact with the element body 11 is referred to as the second outer insulating layer 34A. In this example, the boundary BD between the second outer insulating layer 34A of the second inter-wiring insulating layer 34 and the element body 11 coincides with the boundary BD between the first outer insulating layer 32A of the first inter-wiring insulating layer 32 and the element body 11.

[0066] Here, the outer surfaces of the third interlayer insulating layer 35 that face in a direction parallel to the first main surface 11A are referred to as end surfaces ED. In a specific cross section, there are two end surfaces ED in one location of the third interlayer insulating layer 35. The entire end surface ED is an inclined surface that faces in a direction parallel to the first main surface 11A and in the first negative direction X2. In this example, the inclined surface is planar.

[0067] Also, in the example shown in Figure 24, in a specific cross section, the outermost edge EO of the end face ED of the third interlayer insulating layer 35 is located on a virtual line VL extending the boundary BD between the element body 11 and the second outer insulating layer 34A of the second inter-wiring insulating layer 34 in a direction perpendicular to the first main surface 11A.

[0068] 24 , the entire end face ED of the second interlayer insulating layer 33, which is a surface facing a direction parallel to the first main surface 11A, may be an inclined surface facing a direction parallel to the first main surface 11A and the first negative direction X2. The same applies to the end face ED of the first interlayer insulating layer 31, which is a surface facing a direction parallel to the first main surface 11A. Note that in FIG. 24 , only one end face ED, the outermost edge EO, and the boundary BD are labeled with reference numerals.

[0069] In the above embodiment, the end surface ED is not limited to an inclined surface that is parallel to the first main surface 11A and faces the first negative direction X2. For example, the entire end surface ED may be an inclined surface that is parallel to the first main surface 11A and faces the first positive direction X1.

[0070] In the above embodiment, the end face ED is not limited to being flat. For example, the end face ED may be a curved surface that is convex overall toward the first negative direction X2 or a curved surface that is convex overall toward the first positive direction X1. Furthermore, as long as the entire end face ED faces in a direction parallel to the first main surface 11A and in the first negative direction X2, the curvature of the end face ED may be changed along the way. For example, the end face ED may be flat overall, but may be curved with a rounded chamfer on the first positive direction X1 side.

[0071] In the above embodiment, it is sufficient that at least one of the end faces ED present in the specific cross section is an inclined surface that is parallel to the first main surface 11A and faces the first negative direction X2.

[0072] In the above embodiment, the entire end face of the outer surface of the first interlayer insulating layer 31 facing a direction parallel to the first main surface 11A may be an inclined surface. In this case, among directions orthogonal to the first main surface 11A, the direction from the inductor wiring 50 side toward the first interlayer insulating layer 31 side may be defined as the first positive direction X1, and the direction opposite to the first positive direction X1 may be defined as the first negative direction X2. In this definition, the entire end face of the first interlayer insulating layer 31 may be an inclined surface facing a direction parallel to the first main surface 11A and facing the first negative direction X2, or may be an inclined surface facing a direction parallel to the first main surface 11A and facing the first positive direction X1. Note that in a configuration in which the entire end face of the first interlayer insulating layer 31 is an inclined surface facing one of the above directions, the entire end face ED of the second interlayer insulating layer 33 may also be an inclined surface facing one of the above directions.

[0073] In the above embodiment, the position of the outermost edge EO of the end face ED is not limited to the example of the above embodiment. For example, in a specific cross section, the outermost edge EO of the end face ED of the second interlayer insulating layer 33 may be located on the outer insulating layer 32A side with respect to an imaginary line VL extending the boundary BD between the element body 11 and the outer insulating layer 32A in a direction perpendicular to the first main surface 11A. Also, for example, in the example shown in Figure 25, in a specific cross section, the outermost edge EO of the end face ED of the second interlayer insulating layer 33 is located on the element body 11 side with respect to an imaginary line VL extending the boundary BD between the element body 11 and the outer insulating layer 32A in a direction perpendicular to the first main surface 11A. In other words, when viewed in a direction perpendicular to the first main surface 11A, the outermost edge EO of the end face ED of the second interlayer insulating layer 33 is located outside the area surrounded by the boundary BD between the element body 11 and the outer insulating layer 32A. This configuration ensures connection between the second interlayer insulating layer 33 and the inter-wiring insulating layer 32 while expanding the volume of the magnetic layer 20. In the example shown in Fig. 25, the end of the end face ED on the first negative direction X2 side is also located outside the imaginary line VL, but the end face ED may be located on or inside the imaginary line VL.

[0074] In the above embodiment, when viewed in a direction perpendicular to the first main surface 11A, the entire outermost edge EO of the end face ED of the second interlayer insulating layer 33 does not have to be located within the area surrounded by the boundary BD between the element body 11 and the outer insulating layer 32A. That is, it is sufficient if there is a specific cross section in which the outermost edge EO of the end face ED of the second interlayer insulating layer 33 is located on an imaginary line VL extending the boundary BD between the element body 11 and the outer insulating layer 32A in a direction perpendicular to the first main surface 11A, or on the outer insulating layer 32A side of the imaginary line VL.

[0075] In the above embodiment, the dimension of the second interlayer insulating layer 33 in the direction along the first axis X does not have to be constant. For example, in the example shown in FIG. 25 , the second interlayer insulating layer 33 has a recess 80 recessed toward the first negative direction X2 on the surface facing the first positive direction X1. In this example, the recess 80 can be formed by, for example, irradiating the surface of the second interlayer insulating layer 33 facing the first positive direction X1 with a laser in the state shown in FIG. 16 in the above embodiment. In this example, the outer surface of the recess 80 is curved. This configuration allows for a further increase in the volume of the magnetic material compared to a second interlayer insulating layer 33 with a substantially constant thickness and no recess 80. Note that the recess 80 may also be applied to the first interlayer insulating layer 31.

[0076] In the above embodiment, the synthetic resin SR is not limited to the material of the above embodiment as long as it has insulating properties. Furthermore, the synthetic resin SR can be manufactured by the manufacturing method of the above embodiment as long as it is a photosensitive synthetic resin. Similarly, the material of the filler FL is not limited to the example of the above embodiment. For example, the filler FL may be made of alumina, carbon black, or the like.

[0077] In the above embodiment, the first interlayer insulating layer 31 and the second interlayer insulating layer 33 may not contain the filler FL. That is, the first interlayer insulating layer 31 and the second interlayer insulating layer 33 may be made of only the synthetic resin SR. Furthermore, the inter-wiring insulating layer 32 may contain the filler FL.

[0078] In the above embodiment, the material of the base member 101 is not limited to the example in the above embodiment. For example, the material of the base member 101 may be glass epoxy resin, glass, etc. In the wiring formation process in the above embodiment, a dummy wiring may be formed to connect to the inductor wiring 50. For example, the dummy wiring can be used as a power supply wiring when forming copper plating.

[0079] <Supplementary Notes> Technical concepts that can be derived from the above embodiments and modified examples are described below. [1] An inductor component comprising: an element body having a main surface and containing a magnetic material; an interlayer insulating layer in a plate shape extending parallel to the main surface within the element body; and an inductor wiring in contact with a surface of the interlayer insulating layer that is parallel to the main surface, wherein, among directions orthogonal to the main surface, a direction from the inductor wiring toward the interlayer insulating layer is defined as a positive direction, a direction opposite to the positive direction is defined as a negative direction, and a surface of an outer surface of the interlayer insulating layer that faces a direction parallel to the main surface is defined as an end face, in a specific cross section orthogonal to a center line of the inductor wiring, the entire end face is an inclined surface that faces parallel to the main surface and the negative direction, or an inclined surface that faces parallel to the main surface and the positive direction.

[0080] [2] The inductor component according to [1], further comprising: a columnar wiring that penetrates the interlayer insulating layer in a direction intersecting the main surface and is connected to the inductor wiring. [3] The inductor component according to [1] or [2], wherein the interlayer insulating layer has a recess that is recessed toward the negative direction on the surface facing the positive direction.

[0081] [4] An inductor component according to any one of [1] to [3], further comprising an inter-wiring insulating layer extending from the inter-layer insulating layer in a direction perpendicular to the main surface and having a portion adjacent to the inductor wiring in a direction parallel to the main surface, wherein in the specific cross section, the inter-wiring insulating layer is present in multiple discontinuous locations in a direction along the main surface, and when the location of each location of the inter-wiring insulating layer where the surface facing parallel to the main surface is in contact with the element body is defined as an outer insulating layer, in the specific cross section, the outermost edge of the end face of the inter-layer insulating layer is located on an imaginary line extending the boundary between the element body and the outer insulating layer in a direction perpendicular to the main surface, or on the outer insulating layer side of the imaginary line.

[0082] [5] The inductor component according to any one of [1] to [4], wherein the interlayer insulating layer contains a photocurable synthetic resin and a plurality of fillers dispersed in the synthetic resin.

[0083] BD...boundary ED...end face EO...outermost edge FL...filler X1...first positive direction X2...first negative direction 10...inductor component 11...element body 11A...first main surface 20...magnetic layer 31...first interlayer insulating layer 32...inter-wiring insulating layer 32A...outer insulating layer 33...second interlayer insulating layer 40...columnar wiring 50...inductor wiring 80...recess

Claims

1. A substrate having a main surface and containing a magnetic material, Within the substrate, a flat interlayer insulating layer extending parallel to the main surface, Among the interlayer insulating layers, the inductor wiring that is in contact with the surface parallel to the main surface, Equipped with, When, among the directions perpendicular to the main surface, the direction from the inductor wiring side toward the interlayer insulating layer side is defined as the positive direction, and the direction opposite to the positive direction is defined as the negative direction, and when, among the outer surfaces of the interlayer insulating layer, the surface facing parallel to the main surface is defined as the end face, In a specific cross-section perpendicular to the center line of the inductor wiring, the entire end face is an inclined surface facing in a direction parallel to the main surface and in the negative direction, or an inclined surface facing in a direction parallel to the main surface and in the positive direction. Inductor components.

2. The interlayer insulating layer is further provided with columnar wiring that penetrates the main surface in a direction intersecting it and is connected to the inductor wiring. The inductor component according to claim 1.

3. The interlayer insulating layer has a recess in the plane facing the positive direction that is recessed toward the negative direction. The inductor component according to claim 1.

4. The device further comprises an inter-wiring insulating layer extending from the inter-layer insulating layer in a direction perpendicular to the main surface and having a portion adjacent to the inductor wiring in a direction parallel to the main surface, In the aforementioned specific cross-section, the inter-wiring insulating layer exists discontinuously in multiple locations along the main surface. When the portion of the aforementioned wiring insulation layer in which the surface facing parallel to the main surface is in contact with the base body is defined as the outer insulation layer, In the aforementioned specific cross-section, the outermost edge of the end face of the interlayer insulating layer is located on a virtual line extending in a direction perpendicular to the main surface from the boundary between the base body and the outer insulating layer, or on the outer insulating layer side with respect to said virtual line. The inductor component according to claim 1.

5. The interlayer insulating layer comprises a photocurable synthetic resin and a plurality of fillers dispersed within the synthetic resin. The inductor component according to claim 1.