Inductor components

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

Technical Field

[0001] This disclosure relates to an inductor component.

Background Art

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

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the invention described in Patent Document 1, the first interlayer insulating layer, the inter-wiring insulating layer, and the second interlayer insulating layer are located inside the base body. If the volume of the inductor component is the same, including many insulating layers may reduce the volume of the magnetic material in the base body accordingly.

Means for Solving the Problems

[0005] To solve the above problems, one aspect of the present disclosure is an inductor component comprising: a base body having a main surface and containing a magnetic material; a flat interlayer insulating layer extending parallel to the main surface within the base body; and an inductor wiring in contact with a surface of the interlayer insulating layer parallel to the main surface, wherein, 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 the outer surface of the interlayer insulating layer facing in the direction parallel to the main surface is defined as the end face, the entire end face in a specific cross section perpendicular to the center line of the inductor wiring is an inclined surface facing in the direction parallel to the main surface and the negative direction, or an inclined surface facing in the direction parallel to the main surface and the positive direction. [Effects of the Invention]

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

[0007] [Figure 1] Figure 1 is a perspective view of an inductor component. [Figure 2] Figure 2 is a transparent side view of an inductor component. [Figure 3] Figure 3 is a transparent top view of an inductor component. [Figure 4] Figure 4 is a cross-sectional view of the inductor component along line 4-4 in Figure 3. [Figure 5] Figure 5 is an enlarged cross-sectional view of a specific section. [Figure 6] Figure 6 is a schematic diagram showing an enlarged view of the vicinity of the surface of the first interlayer insulating layer in a specific cross-section. [Figure 7] Figure 7 is an explanatory diagram of the manufacturing method for inductor components. [Figure 8] Figure 8 is an explanatory diagram of the manufacturing method for inductor components. [Figure 9] Figure 9 is an explanatory diagram of the manufacturing method for inductor components. [Figure 10] Figure 10 is an explanatory diagram of the manufacturing method for inductor components. [Figure 11] FIG. 11 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 12] FIG. 12 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 13] FIG. 13 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 14] FIG. 14 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 15] FIG. 15 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 16] FIG. 16 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 17] FIG. 17 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 18] FIG. 18 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 19] FIG. 19 is an explanatory diagram of a method for manufacturing an inductor component. [Figure 20] FIG. 20 is an explanatory diagram of a method for manufacturing an inductor component. <0​​​​​​​​​​​​​​​​​​​​​​​ <About the overall structure> As shown in Figure 1, the inductor component 10 is generally in the shape of a rectangular parallelepiped. As shown in Figure 2, the inductor component 10 comprises a base body 11 and inductor wiring 50.

[0010] As shown in Figure 1, the base body 11 has six planar outer surfaces. Of these six outer surfaces, one specific surface is designated as the first main surface 11A. The surface located opposite the first main surface 11A and parallel to it is designated as the second main surface 11B. Both the outer shape of the first main surface 11A and the outer shape of the second main surface 11B are 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, the axis perpendicular to the first principal surface 11A is defined as the first axis X. The axis perpendicular to the first axis X and parallel to a specific side of the first principal surface 11A, in this embodiment to the long side of the first principal surface 11A, is defined as the second axis Y. Furthermore, the axis perpendicular to both the first axis X and the second axis Y is defined as the third axis Z. The direction along the first axis X that the first principal 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. Furthermore, one 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. Furthermore, one 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 Figure 4, the base body 11 has magnetic layers 20, which are arranged in order from the first negative direction X2 side: 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 Figure 4, the boundaries of each magnetic layer 20 are virtually shown by dashed lines, but clear boundaries may not be observed between these magnetic layers 20. The material of these magnetic layers 20 is an organic resin containing metallic magnetic powder. That is, the base body 11 contains a magnetic material. In this embodiment, the metallic magnetic powder is a metallic magnetic powder made of an Fe-based alloy or amorphous alloy. More specifically, the metallic magnetic powder is an FeSiCr-based metal powder containing iron. Note that the metallic magnetic powder is not limited to FeSiCr-based magnetic powder, but may also be FeCo-based, FeSiAr-based, iron oxide-based, or combinations thereof. The organic resin may also be epoxy-based, imide-based, liquid crystal polymer-based, acrylic-based, phenol-based, or combinations thereof. Furthermore, in addition to the above-mentioned materials, an inorganic filler may be mixed in with the organic resin.

[0013] As shown in Figure 2, the inductor wiring 50 is located inside the base body 11. As shown in Figure 4, the inductor wiring 50 is located in the same place 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% to 1.0 wt%. Note that the inductor wiring 50 is not limited to a conductor mainly composed of copper, but may also be a conductor mainly composed of Ag, Al, and Au.

[0014] As shown in Figure 3, the inductor wiring 50 extends parallel to the first main surface 11A and in a spiral shape. That is, the inductor wiring 50 is linear. As shown in Figure 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 material of the seed layer 51A is copper. As will be described later, by performing electrolytic copper plating on the seed layer 51A, copper grows on the seed layer 51A, and the entire inductor wiring 50 is formed. Note that during 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 Figure 3, the inductor wiring 50 has a pair of pad portions 51P and a wiring 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 designated as the inner pad portion 51PA. The other of the pair of pad portions 51P is designated as the outer pad portion 51PB. When viewed through 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 11. When viewed through in the first negative direction X2, the inner pad portion 51PA is approximately circular in shape. When viewed through 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 11. When viewed through in the first negative direction X2, the outer pad portion 51PB is approximately square in shape.

[0016] The wiring body 51L connects a pair of pad sections 51P. Specifically, when viewing the element 11 through the first negative direction X2, the wiring body 51L extends counterclockwise from the inner pad section 51PA toward the outer pad section 51PB, with the diameter increasing as the number of turns increases. The number of turns of the inductor wiring 50 is 2.5 turns.

[0017] The number of turns in 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 viewed facing the first negative direction X2, and its starting point is located at the first end of the center line, moving it to the second end of the center line, the number of turns is determined to be 1.0 turn when the angle of rotation of the direction of the virtual vector is 360 degrees. However, if the direction of the virtual vector involves multiple windings, the number of turns will increase if the windings are consecutive and in the same direction.

[0018] Furthermore, the centerline of the inductor wiring 50 is determined as follows: When viewing through 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 passing through the center of this identified line segment is defined as the centerline of the inductor wiring 50 when viewing through the first negative direction X2.

[0019] As shown in Figure 4, the inductor component 10 comprises an insulating layer 30 consisting of a first interlayer insulating layer 31, an interwiring 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 base 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 in 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 the direction perpendicular to the first main surface 11A.

[0020] The second interlayer insulating layer 33 is flat. The second interlayer insulating layer 33 extends parallel to the first main surface 11A within the base 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. Note that a partial gap may occur between the inductor wiring 50 and the second interlayer insulating layer 33. The first positive direction X1 is the direction perpendicular to the first main surface 11A, moving from the inductor wiring 50 side towards 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 at the same location as the second interlayer magnetic layer 24 in the direction perpendicular to the first main surface 11A.

[0021] When the side of the inductor wiring 50 facing parallel to the first main surface 11A is considered the side surface, the inter-wiring insulation layer 32 covers the side surface of the inductor wiring 50. Therefore, the inter-wiring insulation layer 32 has a portion adjacent to the inductor wiring 50 in the direction parallel to the first main surface 11A. In this embodiment, the entire inter-wiring insulation layer 32 is adjacent to the inductor wiring 50 in the direction parallel to the first main surface 11A. The inter-wiring insulation layer 32 extends from the second inter-layer insulation layer 33 in a direction perpendicular to the first main surface 11A, i.e., the first negative direction X2. In other words, the inter-wiring insulation layer 32 extends from the first inter-layer insulation layer 31 in the first positive direction X1. Furthermore, in a specific cross-section perpendicular to the centerline of the inductor wiring 50, the inter-wiring insulation layer 32 exists discontinuously in multiple locations along the first main surface 11A. For example, in the specific cross-section shown in Figure 4, the inter-wiring insulation layer 32 exists discontinuously in seven locations along the first main surface 11A. Note that the specific cross-section shown in Figure 4 is a plane that passes through the geometric center of the element 11 and is perpendicular to the second axis Y.

[0022] Here, in a specific cross-section, the portion of the inter-wiring insulation layer 32 where the surface facing parallel to the first main surface 11A is in contact with the base body 11 is defined as the outer insulation layer 32A. In addition, the portion of the inter-wiring insulation layer 32 in a specific cross-section where the surface facing parallel to the first main surface 11A is not in contact with the base body 11 is defined as the inner insulation layer 32B. For example, in the specific cross-section shown in Figure 4, there are four outer insulation layers 32A. Also, in the specific cross-section, there are three inner insulation layers 32B. Specifically, in the specific cross-section, two outer insulation layers 32A are located on the third positive direction Z1 side with respect to the geometric center of the base body 11, and two inner insulation layers 32B are located between these outer insulation layers 32A. The inductor wiring 50 is located between each of these inter-wiring insulation layers 32. Furthermore, two outer insulating layers 32A are located on the third negative direction Z2 side with respect to the geometric center of the element 11, and one inner insulating layer 32B is located between these outer insulating layers 32A. The inductor wiring 50 is located between each of these inter-wiring insulating layers 32. In other words, the inductor wiring 50 is located within the region demarcated by the inter-wiring insulating layers 32.

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

[0024] Specifically, the first columnar wiring 41, which is one of the two columnar wirings 40, consists of a first via 41A and a first lead 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 is substantially cylindrical. 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 location 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 Figure 3, the first lead wire 41B is approximately cylindrical. As shown in Figure 2, the diameter of the first lead wire 41B is slightly larger than the diameter of the first via 41A. The surface of the first lead wire 41B facing the first negative direction X2 is connected to the first via 41A. Therefore, the first lead wire 41B is located at the same location as the third magnetic layer 25 in the direction perpendicular to the first main surface 11A. The surface of the first lead wire 41B facing the first positive direction X1 is exposed from the first main surface 11A.

[0026] As shown in Figure 2, the second columnar wiring 42, which is the other of the two columnar wirings 40, consists of a second via 42A and a second lead wire 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 relative to the first columnar wiring 41. The second via 42A is approximately rectangular prism-shaped. 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 location 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 side of the second via 42A facing the first negative direction X2 side is connected to the outer pad portion 51PB of the inductor wiring 50.

[0027] As shown in Figure 3, the second lead wire 42B is approximately rectangular prism-shaped. As shown in Figure 2, the dimensions of each side of the second lead wire 42B are slightly larger than the dimensions of each side of the second via 42A. The side of the second lead wire 42B facing the first negative direction X2 is connected to the second via 42A. Therefore, the second lead wire 42B is located in the same place as the third magnetic layer 25 in the direction perpendicular to the first main surface 11A. The side of the second lead wire 42B facing the first positive direction X1 is exposed from the first main surface 11A.

[0028] As shown in Figure 1, each external electrode 60 is exposed from the base body 11. Specifically, each external electrode 60 is located on the first main surface 11A of the base body 11. That is, each external electrode 60 covers a portion of the outer surface of the base body 11.

[0029] As shown in Figure 2, the first external electrode 61, 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 the surface of the first lead wiring 41B facing the first positive direction X1. The second external electrode 62, 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 the surface of the second lead wiring 42B facing the first positive direction X1.

[0030] The inductor component 10 is equipped with a solder resist 70. The solder resist 70 covers the portion of the surface of the base body 11 facing the first positive direction X1, excluding the two external electrodes 60. In other words, the first main surface 11A of the base 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 base body 11.

[0031] <Regarding the material of the insulating layer> The materials of the first interlayer insulating layer 31 and the interwiring insulating layer 32 will be described below. Note that 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. Here, "dispersed" means that each filler FL is randomly located within the synthetic resin SR. Therefore, even if some of the fillers FL are aggregated, if the overall arrangement of each filler FL is random, the fillers FL are said to be dispersed. Note that in Figure 6, only some of the fillers FL are labeled with a symbol.

[0033] In this embodiment, the synthetic resin SR is an insulating resin. Specifically, the synthetic resin SR is a polyimide-based resin. This synthetic resin SR is a photocurable resin that hardens when exposed to 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 sides of 500 nm is observed using a scanning electron microscope (SEM). Within this range, the area of ​​the synthetic resin SR, i.e., the area of ​​the area without filler FL, is calculated by image processing. Then, the area ratio is calculated from the area ratio of the total area of ​​the synthetic resin SR to the observed range. This process is repeated three or more times for different cross-sections of the first interlayer insulating layer 31, and the area ratio of each range is calculated. Then, the average value of the calculated area ratios is calculated, and the result is taken as the volume fraction.

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

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

[0036] <Regarding the shape of the second interlayer insulating layer> As shown in Figure 5, the outer surface of the second interlayer insulating layer 33 that faces parallel to the first main surface 11A is defined as the end face ED. In this embodiment, the entire end face ED is planar. As shown in Figure 4, in a specific cross section, there are two end faces ED for each second interlayer insulating layer 33. As shown in Figure 5, in a specific cross section, the entire end face ED is an inclined surface facing parallel to the first main surface 11A and in the first negative direction X2. In the example shown in Figure 5, the end face ED faces the third positive direction Z1 and the first negative direction X2. Thus, the end face 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 Figure 5, the virtual axis coincides with the boundary BD. Note that in a specific cross section perpendicular to the center line of the inductor wiring 50, the entire end face ED is an inclined surface facing the above direction, but in a different cross section, the entire end face ED does not need to be an inclined surface facing the above direction.

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

[0038] Furthermore, as shown in Figure 3, when viewing the inductor component 10 through 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 base body 11 and the outer insulating layer 32A. In other words, as shown in Figure 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 a virtual line VL extended from the boundary BD between the base body 11 and the outer insulating layer 32A in a direction perpendicular to the first main surface 11A. Also, 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] <About the manufacturing method> Next, we will describe the manufacturing method of the inductor component 10. As shown in Figure 7, first, the base preparation process is carried out. 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 top surface. In Figure 7, the dummy insulating layer 102 is shown with a thick line.

[0040] Next, as shown in Figure 8, a first insulating layer processing step is performed to form the first interlayer insulating layer 31. The first interlayer insulating layer 31 is formed on the first positive X1 side surface of the base member 101. Specifically, the first interlayer insulating layer 31 is patterned. The patterning is performed in an area slightly wider than the area where the inductor wiring 50 is arranged. Specifically, the first interlayer insulating layer 31 containing filler FL and 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] Next, as shown in Figure 9, a seed formation process is performed to form the seed layer 51A. Specifically, copper seed portions 103 are formed on the first positive X1 side of the first interlayer insulating layer 31 and the dummy insulating layer 102 by sputtering.

[0042] Next, as shown in Figure 10, a photocurable resist 104 is laminated onto the upper surface of the seed portion 103. Then, only the area of ​​the upper surface of the seed portion 103 in which the seed layer 51A of the inductor wiring 50 is to be formed is exposed to light. The exposed areas of the resist 104 harden. These hardened areas are formed as the covering portion 105. After that, the unhardened parts of the resist 104, i.e., the parts other than the covering portion 105, are removed.

[0043] Next, as shown in Figure 11, the seed portion 103 is etched. This removes the seed portion 103 that is exposed from the covering portion 105. Then, as shown in Figure 12, the coating portion 105 is wet-etched using chemicals. This causes the coating portion 105 to peel off. As a result, the seed layer 51A is formed.

[0044] Subsequently, as shown in Figure 13, a second insulating layer processing step is performed to form the inter-wiring insulating layer 32. Specifically, first, a photocurable permanent resist 106 is laminated to the dummy insulating layer 102, the seed layer 51A, and the first positive direction X1 side of the first inter-layer insulating layer 31. Next, the area where the inter-wiring insulating layer 32 will be formed, that is, the areas located on both sides of the seed layer 51A, are exposed to light.

[0045] Next, as shown in Figure 14, the uncured portion of the permanent resist 106 is peeled off using a chemical solution. This forms the inter-wiring insulating layer 32. The permanent resist 106 consists solely of synthetic resin SR.

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

[0047] Next, as shown in Figure 16, a third insulating layer processing step is performed to form the second interlayer insulating layer 33. The area in which the second interlayer insulating layer 33 is formed is the area on the first positive direction X1 side of the inductor wiring 50 and the inter-wiring insulating layer 32, excluding the areas where the first via 41A and the second via 42A are formed. The second interlayer insulating layer 33 is formed in this area by the same photolithography method used to form the first interlayer insulating layer 31. When forming the second interlayer insulating layer 33 by photolithography, the exposure is adjusted so that the exposure amount on the first positive direction X1 side of the second interlayer insulating layer 33 to be formed is greater than that on 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. At this time, as the ultraviolet light travels through the second interlayer insulating layer 33, it is blocked or scattered by the filler FL and gradually attenuates. Therefore, by irradiating the end of the second interlayer insulating layer 33 on the first negative direction X2 side with ultraviolet light at an intensity such that only a very small amount of light reaches it, the exposure amount can be adjusted as described above. Note that the exposure amount can also be adjusted by, for example, adjusting the irradiation angle of the ultraviolet light. By adjusting the exposure amount in this way, curing is accelerated on the first positive direction X1 side more than on the first negative direction X2 side, and the entire end face ED of the second interlayer insulating layer 33 is formed at an angle so that it faces the first negative direction X2 side. Furthermore, when viewed facing the first negative direction X2, the outermost edge EO of the end face ED of the second interlayer insulating layer 33 coincides with the outermost edge of the interwiring insulating layer 32. Note that in Figure 16, only some of the outermost edges EO are labeled.

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

[0049] Next, as shown in Figure 18, a first magnetic material forming step is performed to form 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 first positive direction X1 side. At this time, the resin containing magnetic powder is applied so as to cover the surface of each columnar wiring 40 on the first positive direction X1 side. Next, the resin containing magnetic powder is hardened by press processing to form the first interlayer magnetic layer 22, the second magnetic layer 23, the second interlayer magnetic layer 24, and the third magnetic layer 25 on the surface of the dummy insulating layer 102 on the first positive direction X1 side.

[0050] Then, the portion of the third magnetic layer 25 on the first positive direction X1 side is scraped until the surface of each columnar wiring 40 on the first positive direction X1 side is exposed. Note that in Figure 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 all shown together as magnetic layer 20 without distinction.

[0051] Next, as shown in Figure 19, a base member cutting process is performed. Specifically, the base member 101 and the dummy insulating layer 102 are completely removed by cutting. As a result of cutting the base member 101 and the dummy insulating layer 102, 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 Figure 20, a second magnetic material forming step is performed to form the first magnetic layer 21. Specifically, first, a resin containing magnetic powder, which is the material for the first magnetic layer 21, is applied to the first negative direction X2 side surface of the first interlayer insulating layer 31 and the first interlayer magnetic layer 22. Then, the resin containing magnetic powder is hardened by press working. After that, the portion of the resin on the first negative direction X2 side is machined. For example, the portion of the resin on the first negative direction X2 side is machined so that the dimension in the direction along the first axis X of the inductor component 10 becomes a desired value. As a result, the first magnetic layer 21 is formed on the first negative direction X2 side surface of the first interlayer insulating layer 31 and the first interlayer magnetic layer 22. Note that in Figure 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 shown together as magnetic layer 20 without distinction.

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

[0054] Next, as shown in Figure 22, an electrode processing step is performed to form the external electrodes 60. The area in which the external electrodes 60 are formed is the area of ​​the third magnetic layer 25 on the first positive direction X1 side and the area of ​​each columnar wiring 40 on the first positive direction X1 side that is not covered by the solder resist 70. Copper, nickel, and gold are electrolessly plated into this area. As a result, the first external electrode 61 and the second external electrode 62 are formed. Note that in Figure 22, the copper, nickel, and gold layers are shown without distinction. Also, as shown in Figure 22, a part of the external electrode 60 may cover a part of the area of ​​the solder resist 70 on the first positive direction X1 side. Next, as shown in Figure 23, a dicing process is performed. Specifically, the parts are diced along the broken line 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 facing in a direction parallel to the first main surface 11A and in the first negative direction X2. In other words, 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 11 can exist in this recessed portion of the end face ED, the volume of the element 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 the case where 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 inclined end face ED, and the columnar wiring 40 is small. In the vicinity of the columnar wiring 40 connected to the inductor wiring 50 of the element 11, there is a risk of magnetic flux concentration when current flows. In such locations where magnetic flux is likely to concentrate, the shape of the end face ED described above ensures that the volume of magnetic material is secured, making it less likely for magnetic flux saturation to occur in the inductor component 10.

[0057] (3) In the above embodiment, in a specific cross-section, the outermost edge EO of the end face ED of the second interlayer insulating layer 33 is located on a virtual line VL that extends the boundary BD between the base 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 viewed through in a direction perpendicular to the first main surface 11A, the second interlayer insulating layer 33 is the minimum size that can cover the interwiring insulating layer 32 and the first interlayer insulating layer 31. In addition to this minimum size of the second interlayer insulating layer 33, the volume of the base body 11 can be increased by the configuration of the end face ED described above, so the proportion occupied by the base body 11 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 forming the second interlayer insulating layer 33, light is blocked or scattered by the fillers FL, so the curing of the synthetic resin SR is not easily promoted on the side opposite to the side to which light is irradiated. Therefore, the dimensions in the surface direction tend to be larger on the side where curing is promoted than on the side where it is not promoted, so this configuration is suitable for making the end face ED an inclined surface.

[0059] <Example of changes> The above embodiments and the following modifications can be combined and implemented to the extent that they do not conflict with each other technically.

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

[0061] In the above embodiment, each columnar wiring 40 is not limited to extending 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 wiring 40 may be located on the first negative direction X2 side relative 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 columnar wiring 40 when viewed through in a direction perpendicular to the first main surface 11A is not limited to the example of the above embodiment. For example, the shapes of each columnar wiring 40 when viewed through 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 shape of the inductor wiring 50 are not limited to the examples of the above embodiment. For example, the inductor wiring 50 may be a straight line with 0 turns.

[0064] In the above embodiment, 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 embodiment, the inductor component 10 may include a plurality of inductor wirings 50. For example, suppose the inductor wiring 50 in the above embodiment is the first inductor wiring 50, the inter-wiring insulation layer 32 is the first inter-wiring insulation layer 32, and the outer insulation layer 32A is the first outer insulation layer 32A. In the example shown in Figure 24, the inductor component 10 further includes a second inductor wiring 52, a second inter-wiring insulation layer 34, and a third inter-layer insulation layer 35. In the example shown in Figure 24, the second inter-wiring insulation layer 34 extends from the second inter-layer insulation layer 33 in the first positive direction X1. The second inductor wiring 52 extends in the region demarcated by the second inter-wiring insulation layer 34, on the side of the second inter-layer insulation layer 33 in the first positive direction X1. The third inter-layer insulation layer 35 extends on the surface of the second inductor wiring 52 and the second inter-wiring insulation layer 34 on the side of the first positive direction X1. In other words, the second inductor wiring 52 is in contact with the 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 towards the third interlayer insulating layer 35. Also, in the example shown in Figure 24, the columnar wiring 40 is connected to the second inductor wiring 52.

[0065] In the example shown in Figure 24, similar to the first inter-wiring insulation layer 32, the second inter-wiring insulation layer 34 exists discontinuously in seven locations along the first main surface 11A in a specific cross-section. Note that Figure 24 shows four of the seven locations of the second inter-wiring insulation layer 34. The first inter-wiring insulation layer 32 is also shown in the same manner. Among the locations of the second inter-wiring insulation layer 34 in a specific cross-section, the location where the surface facing parallel to the first main surface 11A is in contact with the base body 11 is defined as the second outer insulation layer 34A. In this example, the boundary BD between the second outer insulation layer 34A of the second inter-wiring insulation layer 34 and the base body 11 coincides with the boundary BD between the first outer insulation layer 32A of the first inter-wiring insulation layer 32 and the base body 11.

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

[0067] Furthermore, 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 that extends the boundary BD between the base body 11 and the second outer insulating layer 34A of the second interwiring insulating layer 34 in a direction perpendicular to the first main surface 11A.

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

[0069] In the above embodiment, the end face 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 face 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 planar. For example, the end face ED may be a curved surface that is convex to the first negative direction X2 as a whole, or a curved surface that is convex to the first positive direction X1. Also, as long as the entire end face ED is in a direction parallel to the first main surface 11A and facing the first negative direction X2, its curvature may be changed along the end face ED. For example, the end face ED may be planar as a whole, but have a curved surface 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 multiple end faces ED in a particular 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 in a direction parallel to the first main surface 11A may be an inclined surface. In this case, among the directions perpendicular 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 in a direction parallel to the first main surface 11A and in the first negative direction X2, or it may be an inclined surface facing in a direction parallel to the first main surface 11A and in the first positive direction X1. Furthermore, in a configuration in which the entire end face of the first interlayer insulating layer 31 is an inclined surface facing in either of the above directions, the entire end face ED of the second interlayer insulating layer 33 may also be an inclined surface facing in either 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 a virtual line VL that extends the boundary BD between the base 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 base body 11 side with respect to a virtual line VL that extends the boundary BD between the base body 11 and the outer insulating layer 32A in a direction perpendicular to the first main surface 11A. That is, when viewed through 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 region enclosed by the boundary BD between the base body 11 and the outer insulating layer 32A. This configuration allows for an increase in the volume of the magnetic layer 20 while ensuring connection between the second interlayer insulating layer 33 and the interwiring insulating layer 32. In the example shown in Figure 25, the end face ED on the first negative direction X2 side is located outside the virtual line VL, but the end face ED may be located on or inside the virtual line VL.

[0074] In the above embodiment, when viewed through 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 necessarily have to be located within the region enclosed by the boundary BD between the base body 11 and the outer insulating layer 32A. That is, there should be a specific cross-section where the outermost edge EO of the end face ED of the second interlayer insulating layer 33 lies on a virtual line VL extended from the boundary BD between the base 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 with respect to the virtual 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 Figure 25, the second interlayer insulating layer 33 has a recess 80 on the surface facing the first positive direction X1 that is recessed toward the first negative direction X2. In this example, the recess 80 can be formed by irradiating the surface of the second interlayer insulating layer 33 facing the first positive direction X1 with a laser, in the state shown in Figure 16 of the above embodiment. The outer surface of the recess 80 in this example is curved. With this configuration, the volume of magnetic material can be further increased compared to the case in which a second interlayer insulating layer 33 with substantially constant thickness and without the recess 80 is used. Note that the recess 80 may also be applied to the first interlayer insulating layer 31.

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

[0077] In the above embodiment, the first interlayer insulating layer 31 and the second interlayer insulating layer 33 do not necessarily contain filler FL. That is, the first interlayer insulating layer 31 and the second interlayer insulating layer 33 may be composed only of synthetic resin SR. Also, the interwiring insulating layer 32 may contain filler FL.

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

[0079] <Note> The technical concepts that can be derived from the above embodiments and modifications are described below. [1] An inductor component comprising: a body having a main surface and containing a magnetic material; a flat interlayer insulating layer extending parallel to the main surface within the body; and an inductor wiring in contact with a surface of the interlayer insulating layer parallel to the main surface, wherein, 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, the direction opposite to the positive direction is defined as the negative direction, and when the outer surface of the interlayer insulating layer facing in the direction 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 the direction parallel to the main surface and in the negative direction, or an inclined surface facing in the direction parallel to the main surface and in 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 in the plane facing the positive direction that is recessed toward the negative direction.

[0081] [4] The inductor component according to any one of [1] to [3], further comprising an inter-wiring insulating layer extending from the interlayer 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 exists discontinuously in multiple locations along the main surface, and when the portion of the inter-wiring insulating layer whose surface facing in a direction parallel to the main surface is in contact with the base body is defined as the outer insulating layer, the outermost edge of the end face of the interlayer insulating layer in the specific cross section is located on a virtual line extending the boundary between the base body and the outer insulating layer in a direction perpendicular to the main surface, or on the outer insulating layer side with respect to the virtual line.

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

[0083] BD…boundary ED…End face EO... outermost edge FL... Filler X1…first positive direction X2…1st negative direction 10…Inductor components 11... Base body 11A…1st main surface 20...Magnetic layer 31…First interlayer insulating layer 32…Insulation layer between wiring 32A…Outer insulation layer 33…Second interlayer insulating layer 40…Column 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.