Electronic components

Abstract

The present disclosure provides an electronic component that can reduce the resistance of a circuit when connected to an external circuit. The electronic component comprises a composite body composed of a composite material of a resin and a metal magnetic powder; an internal electrode disposed in the composite body and with an end face exposed from an outer surface of the composite body; and a metal film disposed on the outer surface of the composite body and on the end face of the internal electrode, the metal film having a first region and a second region, the first region being disposed on the end face of the internal electrode, the second region being in contact with the metal magnetic powder exposed in the outer surface and disposed on the outer surface of the composite body, the first region having a thickness smaller than the second region.

Description

Technical Field

[0001] The present disclosure relates to an electronic component. Background Art

[0002] In the past, there is an electronic component described in Japanese Patent Publication No. 2017-103423 (Patent Document 1). The electronic component of Patent Document 1 includes: a composite body composed of a composite material of resin and metal magnetic powder; an internal electrode disposed in the composite body with an end face exposed from the outer surface of the composite body; and a metal film disposed on the outer surface of the composite body and the end face of the internal electrode.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2017-103423 Summary of the invention

[0004] However, it is known that in the above-mentioned electronic components, when the metal film is used to connect to the external circuit, the resistance of the electronic components has room for improvement. The inventors have conducted intensive research and found that the resistance between the external circuit and the end surface of the internal electrode, that is, the resistance of the metal film, has room for improvement.

[0005] Specifically, in the electronic component described above, when the external circuit is connected using a metal film arranged on the end surface of the internal electrode, the resistance of the line between the external circuit and the internal electrode (hereinafter also referred to as circuit resistance) can be reduced by uniformly reducing the thickness of the entire metal film.

[0006] However, when the external circuit is connected by a metal film disposed on the outer surface of the composite, the circuit resistance cannot be reduced even if the thickness of the metal film is uniformly reduced. It can be seen that the circuit resistance cannot be sufficiently reduced depending on the position of the metal film to which the external circuit is connected.

[0007] Therefore, the present disclosure provides an electronic component capable of reducing resistance when connected to an external circuit.

[0008] In order to solve the above-mentioned problems, an electronic component as one embodiment of the present disclosure includes:

[0009] The composite body is composed of a composite material of resin and metal magnetic powder.

[0010] an internal electrode disposed in the composite body and having an end surface exposed from an outer surface of the composite body, and

[0011] a metal film disposed on the outer surface of the composite body and the end surface of the internal electrode;

[0012] The metal film has a first region and a second region, the first region is arranged on the end surface of the internal electrode, and the second region is arranged on the outer surface of the composite body in contact with the metal magnetic powder exposed on the outer surface.

[0013] The thickness of the first region is smaller than the thickness of the second region.

[0014] According to the above embodiment, when the electronic component is connected to the external circuit through the first region, the thickness of the first region becomes a factor determining the length of the line between the external circuit and the internal electrode. At this time, since the thickness of the first region can be reduced, the length of the line can be shortened and the circuit resistance can be reduced.

[0015] On the other hand, when the electronic component is connected to an external circuit through the second region, the thickness of the second region becomes a factor determining the cross-sectional area of ​​the line between the external circuit and the internal electrode. In this case, since the thickness of the second region can be increased, the cross-sectional area of ​​the line can be increased, and the circuit resistance can be reduced.

[0016] Therefore, the circuit resistance can be reduced in any case.

[0017] Here, the "thickness of the first region" refers to the thickness of the first region in a direction perpendicular to the surface of the composite body on which the metal film is provided. The "thickness of the second region" refers to the thickness of the second region in a direction perpendicular to the surface of the composite body on which the metal film is provided.

[0018] According to the electronic component as one embodiment of the present disclosure, it is possible to provide an electronic component that can reduce line resistance when connected to an external circuit regardless of the position of a metal film to be connected to the external circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1A This is a perspective plan view showing a first embodiment of an inductor component as an electronic component.

[0020] Figure 1B yes Figure 1A AA cross-section diagram.

[0021] Figure 2 yes Figure 1B A partial enlarged view of .

[0022] Figure 3 yes Figure 1B A partial enlarged view of .

[0023] Figure 4A This is an explanatory diagram for explaining a method for manufacturing an inductor component.

[0024] Figure 4BThis is an explanatory diagram for explaining a method for manufacturing an inductor component.

[0025] Figure 4C This is an explanatory diagram for explaining a method for manufacturing an inductor component.

[0026] Figure 4D This is an explanatory diagram for explaining a method for manufacturing an inductor component.

[0027] Figure 5 This is a partially enlarged view of the second embodiment.

[0028] Explanation of symbols

[0029] 1Inductor parts (electronic parts)

[0030] 2A No. 1 Inductor Component

[0031] 2B Second inductor element

[0032] 10 green body

[0033] 101 1st edge

[0034] 102 2nd edge

[0035] 10a 1st main side

[0036] 10b Side 1

[0037] 10c Side 2

[0038] 111st magnetic layer

[0039] 12 Second magnetic layer

[0040] 12a Upper surface of the second magnetic layer

[0041] 211st Inductor Wiring

[0042] 222nd inductor wiring

[0043] 31 1st columnar wiring

[0044] 31 End surface of the first columnar wiring

[0045] 32 2nd columnar wiring

[0046] 33 3rd column wiring

[0047] 34 4th column wiring

[0048] 41 1st external terminal

[0049] 410 metal film

[0050] 410a Area 1

[0051] 410b Area 2

[0052] 411 1st coating layer

[0053] 412 Second coating layer

[0054] 42 2nd external terminal

[0055] 43 3rd external terminal

[0056] 44 4th external terminal

[0057] 50 Insulation film

[0058] 61 Insulation layer

[0059] 100 motherboard

[0060] 135 resin

[0061] 136 Metal magnetic powder

[0062] T1 Thickness of the first area

[0063] T2 Thickness of the second area DETAILED DESCRIPTION

[0064] Hereinafter, an electronic component as one embodiment of the present disclosure will be described in detail by way of the illustrated embodiments. It should be noted that the drawings include some schematic diagrams and may not reflect actual dimensions and ratios.

[0065] (First embodiment)

[0066] (constitute)

[0067] Figure 1A It is a perspective plan view showing the first embodiment of the electronic component. Figure 1B yes Figure 1A AA cross-section diagram.

[0068] As an example, the electronic component is an inductor component 1. The inductor component 1 is, for example, a surface-mounted electronic component, and is mounted on a circuit board mounted on electronic devices such as personal computers, DVD players, digital cameras, TVs, mobile phones, and automotive electronic products. However, the inductor component 1 may also be a substrate-embedded electronic component instead of a surface-mounted type. In addition, the inductor component 1 is, for example, a component that is a rectangular parallelepiped as a whole. However, the shape of the inductor component 1 is not particularly limited, and may also be a cylindrical shape, a polygonal cylindrical shape, a conical trapezoidal shape, or a polygonal conical trapezoidal shape.

[0069] like Figure 1A and Figure 1BAs shown in FIG. 1 , the inductor component 1 includes: a base body 10 having insulating properties, a first inductor element 2A and a second inductor element 2B arranged in the base body 10, a first columnar wiring 31, a second columnar wiring 32, a third columnar wiring 33, and a fourth columnar wiring 34 embedded in the base body 10 and having their end faces exposed from a rectangular first main surface 10a of the base body 10, a first external terminal 41, a second external terminal 42, a third external terminal 43, and a fourth external terminal 44 arranged on the first main surface 10a of the base body 10, and an insulating film 50 provided on the first main surface 10a of the base body 10. In the figure, a direction parallel to the thickness of the inductor component 1 is defined as a Z direction, a positive Z direction is defined as an upper side, and a reverse Z direction is defined as a lower side. In a plane orthogonal to the Z direction, a direction parallel to the length of the long side of the inductor component 1 is defined as an X direction, and a direction parallel to the width of the short side of the inductor component 1 is defined as a Y direction.

[0070] The body 10 includes an insulating layer 61, a first magnetic layer 11 disposed on a lower surface 61a of the insulating layer 61, and a second magnetic layer 12 disposed on an upper surface 61b of the insulating layer 61. The first main surface 10a of the body 10 corresponds to the upper surface of the second magnetic layer 12. The body 10 has a three-layer structure of the insulating layer 61, the first magnetic layer 11, and the second magnetic layer 12, but may also have a single-layer structure of only a magnetic layer, a two-layer structure of only a magnetic layer and an insulating layer, or a four-layer or more structure consisting of a plurality of magnetic layers and an insulating layer.

[0071] The insulating layer 61 has insulating properties, and the main surface is a rectangular layer. The thickness of the insulating layer 61 is, for example, 10 μm to 100 μm. For example, from the perspective of low height, the insulating layer 61 is preferably an insulating resin layer of epoxy resin, polyimide resin, etc. without a substrate such as glass cloth, but it can also be a sintered body layer composed of a magnetic body such as ferrite, such as Ni-Zn system, Mn-Zn system, alumina, glass, etc., and can also be a resin substrate layer containing a substrate such as glass epoxy resin. It should be noted that when the insulating layer 61 is a sintered body layer, the strength and flatness of the insulating layer 61 can be ensured, and the processability of the laminate on the insulating layer 61 is improved. In addition, when the insulating layer 61 is a sintered body layer, from the perspective of low height, it is preferably ground, and it is particularly preferred to grind from the lower side without the laminate.

[0072] The first magnetic layer 11 and the second magnetic layer 12 have high magnetic permeability, and the main surface is a rectangular layer, and contains a resin 135 and a metal magnetic powder 136 contained in the resin 135. That is, the first magnetic layer 11 and the second magnetic layer 12 are a composite containing the resin 135 and the metal magnetic powder 136. The resin 135 is, for example, an organic insulating material composed of epoxy resin, bismaleimide, liquid crystal polymer, polyimide, etc. The metal magnetic powder 136 preferably contains Fe, and examples thereof include magnetic metal materials such as Fe elemental substance, Fe-Si alloys such as Fe-Si-Cr, Fe-Co alloys, Fe alloys such as Ni-Fe, or their amorphous alloys. The average particle size of the metal magnetic powder 136 is, for example, 0.1μm to 5μm. In the manufacturing stage of the inductor component 1, it can be used as a particle size equivalent to 50% of the cumulative value in the particle size distribution obtained by the laser diffraction and refraction method (i.e., D 50 ) and calculate the average particle size of the metal magnetic powder 136. The content of the metal magnetic powder 136 is preferably 20 Vol% to 70 Vol% relative to the entire magnetic layer. When the average particle size of the metal magnetic powder 136 is 5 μm or less, the DC superposition characteristics are further improved, and the iron loss at high frequencies can be reduced by fine powder.

[0073] The first inductor element 2A and the second inductor element 2B include a first inductor wiring 21 and a second inductor wiring 22 arranged in parallel with the first main surface 10a of the base body 10. Thus, the first inductor element 2A and the second inductor element 2B can be formed in a direction parallel to the first main surface 10a, and the height of the inductor component 1 can be reduced. The first inductor wiring 21 and the second inductor wiring 22 are arranged on the same plane in the base body 10. Specifically, the first inductor wiring 21 and the second inductor wiring 22 are formed only on the upper side of the insulating layer 61, that is, the upper surface 61b of the insulating layer 61, and are covered by the second magnetic layer 12.

[0074] The first and second inductor wirings 21 and 22 are wound in a plane. Specifically, when viewed from the Z direction, the first and second inductor wirings 21 and 22 are semi-elliptical arcs. That is, the first and second inductor wirings 21 and 22 are curved wirings wound about half a turn. In addition, the first and second inductor wirings 21 and 22 include a straight portion in the middle. It should be noted that in the present application, the "spiral" of the inductor wiring refers to a curved shape wound in a plane including a vortex shape, and also includes a curved shape with less than one turn such as the first inductor wiring 21 and the second inductor wiring 22. In addition, the curved shape may also include a partial straight portion.

[0075] The thickness of the first and second inductor wires 21 and 22 is preferably 40 μm to 120 μm, for example. As an example of the first and second inductor wires 21 and 22, the thickness is 45 μm, the wire width is 40 μm, and the space between wires is 10 μm. From the viewpoint of ensuring insulation, the space between wires is preferably 3 μm to 20 μm.

[0076] The first and second inductor wirings 21 and 22 are made of a conductive material, for example, a metal material with a low resistance such as Cu, Ag, Au, etc. In the present embodiment, the inductor component 1 includes only one layer of the first and second inductor wirings 21 and 22, which can reduce the height of the inductor component 1. It should be noted that the first and second inductor wirings 21 and 22 may also be a metal film, for example, a structure in which a conductive layer of Cu, Ag, etc. is formed on a base layer of Cu, Ti, etc. formed by chemical plating.

[0077] The first inductor wiring 21 is electrically connected to the first columnar wiring 31 and the second columnar wiring 32, whose first and second ends are located outside, respectively, and is in a curved shape that describes an arc from the first columnar wiring 31 and the second columnar wiring 32 toward the center side of the inductor component 1. In addition, the first inductor wiring 21 has a pad portion at both ends thereof whose line width is larger than that of the spiral-shaped portion, and is directly connected to the first and second columnar wirings 31 and 32 at the pad portion.

[0078] Similarly, the second inductor wiring 22 is electrically connected to the third columnar wiring 33 and the fourth columnar wiring 34 whose first and second ends are located outside, respectively, and has a curved shape that describes an arc from the third columnar wiring 33 and the fourth columnar wiring 34 toward the center of the inductor component 1 .

[0079] Here, in the first and second inductor wirings 21 and 22, the range surrounded by the curved lines drawn by the first and second inductor wirings 21 and 22 and the straight line connecting the two ends of the first and second inductor wirings 21 and 22 is defined as the inner diameter portion. At this time, when viewed from the Z direction, the inner diameter portions of the first and second inductor wirings 21 and 22 do not overlap each other, and the first and second inductor wirings 21 and 22 are separated from each other.

[0080] The wiring further extends from the connection position of the first and second inductor wirings 21 and 22 with the first to fourth columnar wirings 31 to 34 toward a direction parallel to the X direction and to the outside of the inductor component 1, and the wiring is exposed to the outside of the inductor component 1. That is, the first and second inductor wirings 21 and 22 have an exposed portion 200 exposed to the outside from a side surface parallel to the stacking direction of the inductor component 1 (a surface parallel to the YZ plane).

[0081] This wiring is a wiring connected to the power supply wiring when additional plating is performed after the first and second inductor wirings 21 and 22 are formed in the manufacturing process of the inductor component 1. Additional plating can be easily performed in the inductor substrate state before the inductor component 1 is singulated by the power supply wiring, and the distance between wirings can be narrowed. In addition, by performing additional plating, the distance between wirings of the first and second inductor wirings 21 and 22 is narrowed, thereby improving the magnetic coupling of the first and second inductor wirings 21 and 22, or increasing the wiring width of the first and second inductor wirings 21 and 22 to reduce resistance, or miniaturizing the outer shape of the inductor component 1.

[0082] In addition, since the first and second inductor wirings 21 and 22 have an exposed portion 200, the electrostatic breakdown resistance during the processing of the inductor substrate can be ensured. In each inductor wiring 21 and 22, the thickness (dimension along the Z direction) of the exposed surface 200a of the exposed portion 200 is preferably less than the thickness (dimension along the Z direction) of each inductor wiring 21 and 22 and greater than 45μm. By making the thickness of the exposed surface 200a less than the thickness of the inductor wiring 21 and 22, the proportion of the magnetic layers 11 and 12 can be increased, and the inductance can be improved. In addition, by making the thickness of the exposed surface 200a greater than 45μm, the occurrence of broken wires near the exposed surface 200a can be reduced. The exposed surface 200a is preferably an oxide film. As a result, short circuits can be suppressed between the inductor component 1 and its adjacent components.

[0083] The first to fourth pillar-shaped wirings 31 to 34 extend from the inductor wirings 21 and 22 in the Z direction and penetrate the interior of the second magnetic layer 12. The first pillar-shaped wiring 31 extends upward from the upper surface of one end of the first inductor wiring 21, and the end surface of the first pillar-shaped wiring 31 is exposed from the first main surface 10a of the base body 10. The second pillar-shaped wiring 32 extends upward from the upper surface of the other end of the first inductor wiring 21, and the end surface of the second pillar-shaped wiring 32 is exposed from the first main surface 10a of the base body 10. The third pillar-shaped wiring 33 extends upward from the upper surface of one end of the second inductor wiring 22, and the end surface of the third pillar-shaped wiring 33 is exposed from the first main surface 10a of the base body 10. The fourth pillar-shaped wiring 34 extends upward from the upper surface of the other end of the second inductor wiring 22, and the end surface of the fourth pillar-shaped wiring 34 is exposed from the first main surface 10a of the base body 10.

[0084] Therefore, the first columnar wiring 31, the second columnar wiring 32, the third columnar wiring 33, and the fourth columnar wiring 34 extend linearly from the first inductor element 2A and the second inductor element 2B to the end surface exposed from the first main surface 10a in a direction perpendicular to the end surface. As a result, the first external terminal 41, the second external terminal 42, the third external terminal 43, and the fourth external terminal 44 can be connected to the first inductor element 2A and the second inductor element 2B at a shorter distance, and the inductor component 1 can achieve lower resistance and higher inductance. The first to fourth columnar wirings 31 to 34 are made of a conductive material, for example, the same material as the inductor wirings 21 and 22.

[0085] The first to fourth external terminals 41 to 44 are arranged on the first main surface 10 a of the body 10 .

[0086] The first to fourth external terminals 41 to 44 are metal films disposed on the outer surface of the second magnetic layer 12. The first external terminal 41 is in contact with the end surface of the first columnar wiring 31 exposed from the first main surface 10a of the base body 10, and is electrically connected to the first columnar wiring 31. Thus, the first external terminal 41 is electrically connected to one end of the first inductor wiring 21. The second external terminal 42 is in contact with the end surface of the second columnar wiring 32 exposed from the first main surface 10a of the base body 10, and is electrically connected to the second columnar wiring 32. Thus, the second external terminal 42 is electrically connected to the other end of the first inductor wiring 21.

[0087] Similarly, the third external terminal 43 is in contact with the end surface of the third columnar wiring 33, is electrically connected to the third columnar wiring 33, and is electrically connected to one end of the second inductor wiring 22. The fourth external terminal 44 is in contact with the end surface of the fourth columnar wiring 34, is electrically connected to the fourth columnar wiring 34, and is electrically connected to the other end of the second inductor wiring 22.

[0088] In the inductor component 1, the first main surface 10a has a first edge 101 and a second edge 102 extending in a straight line corresponding to the sides of a rectangle. The first edge 101 and the second edge 102 are edges of the first main surface 10a connected to the first side surface 10b and the second side surface 10c of the green body 10, respectively. The first external terminal 41 and the third external terminal 43 are arranged along the first edge 101 on the first side surface 10b side of the green body 10, and the second external terminal 42 and the fourth external terminal 44 are arranged along the second edge 102 on the second side surface 10c side of the green body 10. It should be noted that the first side surface 10b and the second side surface 10c of the green body 10 are surfaces along the Y direction when viewed from a direction orthogonal to the first main surface 10a of the green body 10, and coincide with the first edge 101 and the second edge 102. The arrangement direction of the first external terminal 41 and the third external terminal 43 is the direction connecting the center of the first external terminal 41 and the center of the third external terminal 43, and the arrangement direction of the second external terminal 42 and the fourth external terminal 44 is the direction connecting the center of the second external terminal 42 and the center of the fourth external terminal 44.

[0089] The insulating film 50 is provided on the portion of the first main surface 10a of the blank 10 where the first to fourth external terminals 41 to 44 are not provided. However, the insulating film 50 may overlap the first to fourth external terminals 41 to 44 in the Z direction by covering the ends of the first to fourth external terminals 41 to 44. The insulating film 50 is made of a resin material having high electrical insulation, such as acrylic resin, epoxy resin, polyimide, etc. Thus, the insulation between the first to fourth external terminals 41 to 44 can be improved. In addition, the insulating film 50 replaces the mask when the pattern of the first to fourth external terminals 41 to 44 is formed, and the manufacturing efficiency is improved. In addition, the insulating film 50 can prevent the metal magnetic powder 136 from being exposed to the outside by covering the exposed metal magnetic powder 136 when the metal magnetic powder 136 is exposed from the resin 135. It should be noted that the insulating film 50 may contain a filler composed of an insulating material such as silicon dioxide and barium sulfate.

[0090] Figure 2 for Figure 1B Enlarged view of part A. Figure 3 for Figure 1B A magnified view of part B. Figure 2 and Figure 3As shown, the external terminal 41 is composed of a metal film 410 arranged on the upper surface 12a of the second magnetic layer 12 and the end surface 31a of the first columnar wiring 31, a first coating layer 411 arranged on the metal film 410, and a second coating layer 412 arranged on the first coating layer 411. The metal film 410 has a first region 410a arranged on the end surface 31a of the first columnar wiring 31 and a second region 410b arranged on the upper surface 12a of the second magnetic layer 12. The thickness T1 of the first region 410a is smaller than the thickness T2 of the second region 410b (hereinafter also referred to as "T1 < T2").

[0091] It should be noted that the configurations of the second, third, and fourth external terminals 42, 43, and 44 are the same as the configuration of the first external terminal 41, and therefore, only the first external terminal 41 will be described below. Figure 2 In the figure, for convenience of explanation, the covering layers 411 and 412 constituting a part of the first external terminal 41 are omitted.

[0092] The thickness T1 of the first region 410a is smaller than the thickness T2 of the second region 410b. When the inductor component 1 is connected to an external circuit using the first region 410a, the thickness T1 of the first region 410a can be reduced, thereby shortening the line length and reducing the circuit resistance.

[0093] On the other hand, when the inductor component 1 is connected to an external circuit using the second region T2, the thickness of the second region T2 can be increased, thereby increasing the cross-sectional area of ​​the line and reducing the circuit resistance. Therefore, the circuit resistance can be reduced in either case.

[0094] In short, as shown in the prior art, when the overall thickness of the metal film 410 is uniformly controlled, it is sometimes impossible to sufficiently reduce the circuit resistance through the connection parts of the metal film. In order to solve such a problem, the present inventors conducted in-depth research and found the following technical insights: the thickness of the metal film 410 has different effects on the circuit resistance depending on the connection parts of the metal film 410 with the external circuit. The structure of "T1<T2" disclosed in the present invention is the result of further research by the present inventors, and the thickness of the metal film 410 is set and derived according to different effects based on this technical insight.

[0095] To explain in detail, when the inductor component 1 is connected to an external circuit using the first region 410a, the thickness T1 of the first region 410a becomes a factor that determines the length of a line between the external circuit and the first columnar wiring 31. By reducing the thickness T1 of the first region 410a, the length of the line can be shortened, and the circuit resistance can be reduced.

[0096] On the other hand, when the inductor component 1 is connected to an external circuit using the second region 410b, the thickness T2 of the second region 410b becomes a factor that determines the cross-sectional area of ​​the line between the external circuit and the first columnar wiring 31. Since the thickness T2 of the second region 410b can be increased, the cross-sectional area of ​​the line can be increased, and the circuit resistance can be reduced.

[0097] As a result, the circuit resistance can be reduced regardless of the connection position between the external circuit and the metal film.

[0098] The above-mentioned “thickness T1 of the first region 410a” refers to the thickness of the first region 410a of the metal film 410 in the direction perpendicular to the surface on which the metal film 410 is provided in the first main surface 10a of the body 10. Similarly, the above-mentioned “thickness T2 of the second region 410b” refers to the thickness of the second region 410b of the metal film 410 in the direction perpendicular to the surface on which the metal film 410 is provided in the first main surface 10a of the body 10.

[0099] The "thickness T1 of the first region 410a" and the "thickness T2 of the second region 410b" are values ​​obtained from the FIB-SIM image of the cross section of the inductor component 1. The FIB-SIM image is a cross-sectional image obtained by SIM (Scanning Ion Microscope) observation using FIB (Focused Ion Beam). The image can be analyzed using image processing software (for example, "A-image" (registered trademark) manufactured by Asahi Kasei Engineering Corporation).

[0100] The above cross section Figure 1B The thickness T1 of the first region 410a and the thickness T2 of the second region 410b only need to satisfy T1<T2 in at least one of the three thickness determining regions shown below.

[0101] In the first thickness determination region, the thickness T1 of the first region 410a is the thickness of the first region 410a at the first center C1, which is the center between the first interface B1 (corresponding to the outer side surface of the first columnar wiring 31) between the second magnetic layer 12 and the first columnar wiring 31 and the second interface B2 (corresponding to the inner side surface of the first columnar wiring 31) between the second magnetic layer 12 and the first columnar wiring 31. The thickness T2 of the second region 410b is the thickness of the second region 410b at the second center C2, which is the center between the second interface B2 and the third interface B3 between the metal film 410 and the insulating film 50.

[0102] In the second thickness determination region, the thickness T1 of the first region 410a is the thickness T1 of the first region 410a ranging from the first center C1 to the first and second interfaces B1 and B2 sides to the length R1, respectively. The thickness T2 of the second region 410b is the thickness T2 of the second region 410b ranging from the second center C2 to the second and third interfaces B2 and B3 sides to the length R2, respectively.

[0103] In the third thickness determining region, the thickness T1 of the first region 410a is the thickness of the first region 410a between the first interface B1 and the second interface B2 and does not include the thickness of the first region in the region P1 ranging from the first interface B1 and the second interface B2 to the first columnar wiring 31 side to the length r1 respectively.

[0104] The thickness T2 of the second region 410b is the thickness of the second region 410b in the second region 410 between the second interface B2 and the third interface B3, excluding the range from the second interface B2 to the third interface B3 side to the length r2 and the range from the third interface B3 to the second interface B2 side to the length r3.

[0105] In the second and third thickness determination regions, a plurality of locations may be measured (for example, the number of measurements n=3, 5, etc.), and the average value of the plurality of measured values ​​may be used as the thickness T1, T2 of the first and second regions 410a, 410b.

[0106] The length between the first interface B1 and the first center C1 (the length in the X direction) is greater than the sum of the lengths r1 and R1. The length between the second interface B2 and the second center C2 (the length in the X direction) is greater than the sum of the lengths r2 and R2. The length between the second center C2 and the third interface B3 (the length in the X direction) is greater than the sum of the lengths R2 and r3. Considering the range in which the thicknesses T1 and T2 of the first and second regions 410a and 410b can be measured, that is, the widths of the first and second regions 410a and 410b, the lengths r1, r2, r3, R1 and R2 are, for example, each independently 3 to 10 μm.

[0107] The lengths r1, r2, and r3 may be the same as or different from each other. The lengths R1 and R2 may be the same as or different from each other.

[0108] The ratios of the lengths r1 and R1 to the width (length in the X direction) of the first region 410a are, for example, independently 5% to 50%. The ratios of the lengths r2, r3, and R2 to the width (length in the X direction) of the second region 410b are, for example, independently 5% to 50%.

[0109] In the image analysis of the FIB-SIM image, the position of the interface is visually confirmed using the color tone (e.g., contrast, etc.) of the FIB-SIM image. The thickness T1 of the first region 410a and the thickness T2 of the second region 410b are thereby measured. Here, the interface between the structures formed by similar materials can also be visually confirmed. For example, even in the case where the first columnar wiring 31 and the metal film 410 are composed of Cu as the main component, the interface between the first columnar wiring 31 and the metal film 410 can be visually confirmed. Specifically, in the case where the first columnar wiring 31 is formed using an electroplating method and the metal film 410 is formed by a chemical plating method, the first columnar wiring 31 has a structure with higher crystallinity than the metal film 410. The existence of the above-mentioned interface can be confirmed based on the difference in crystallinity caused by different manufacturing methods. In addition, when the first pillar wiring 31 is substantially composed of Cu, and a trace component (e.g., Ni, etc.) is added to the main component Cu to form the metal film 410, if the obtained FIB-SIM image is subjected to energy dispersive X-ray (EDX) mapping, the position where the trace component is distributed (i.e., the metal film 410) can be determined. Thus, the presence of the above-mentioned interface can be confirmed by the presence or absence of a specific trace component.

[0110] As described above, the first external terminal 41 includes the metal film 410, the first coating layer 411, and the second coating layer 412. If the coating layers 411 and 412 covering the metal film 410 are further provided, the metal film 410 and the coating layers 411 and 412 can each have different functions, thereby adding a new function to the metal film 410.

[0111] The metal film 410 mainly includes Cu. The metal film 410 is preferably composed of a metal or alloy containing Cu. As a result, a metal film 410 with high conductivity is obtained. In particular, when the metal magnetic powder 136 includes Fe and the metal film 410 is formed by plating, the metal film 410 can be formed more easily. This is because the Fe contained in the metal magnetic powder 136 and the Cu contained in the plating solution undergo a substitution reaction to form the metal film 410. In addition, the metal film 410 preferably further includes Ni. If the metal film 410 includes Ni, the internal stress accumulated in the metal film 410 is relaxed.

[0112] In the second region 410b, the thickness of the metal film 410 is greater than the total thickness of the first and second coating layers 411 and 412. At this time, if the metal film 410 is made of Cu, the thickness of the second region 410b made of Cu having excellent conductivity is the largest, thereby reducing the circuit resistance.

[0113] The first coating layer 411 is a metal film that directly covers the metal film 410 and includes, for example, Ni, etc. The first coating layer 411 has a function of suppressing migration of the metal film 410 and solder corrosion.

[0114] The second covering layer 412 is a metal film that directly covers the first covering layer 411 and constitutes the outermost layer of the first external terminal 41, and includes, for example, Au, Sn, etc. The second covering layer 412 has a function of ensuring solder wettability.

[0115] The second magnetic layer 12 has an upper surface 12a in contact with the metal film 410, and at least one metal magnetic powder 136 is exposed on the upper surface 12a. Therefore, the metal film 410 is disposed on the upper surface 12a of the second magnetic layer 12 and in contact with the exposed surface of the upper surface 12a.

[0116] (Manufacturing method)

[0117] Next, a method for manufacturing the inductor component 1 will be described.

[0118] like Figure 4A As shown in FIG. 1 , in a state where the plurality of inductor wirings 21 and 22 and the plurality of columnar wirings 31 to 34 are covered by the base body 10, the upper surface of the base body 10 is ground by grinding or the like, so that the end faces of the columnar wirings 31 to 34 are exposed from the upper surface of the base body 10. Figure 4B As shown, an insulating film 50 indicated by hatching is formed on the entire upper surface of the base body 10 by a coating method such as spin coating or screen printing, or a dry method such as dry film resist affixing. The insulating film 50 is, for example, a photosensitive resist.

[0119] Thereafter, in the region where the external terminal is to be formed, the insulating film 50 is removed by photolithography, laser, drilling, sandblasting, or the like, thereby forming through holes 50a in the insulating film 50 through which the end faces of the columnar wirings 31 to 34 and a portion of the base body 10 (second magnetic layer 12) are exposed. Figure 4B As shown, the entire end surface of the columnar wirings 31 to 34 is exposed from the through hole 50a, or a portion of the end surface of the columnar wirings 31 to 34 may be exposed. Alternatively, the end surfaces of a plurality of columnar wirings 31 to 34 may be exposed from one through hole 50a.

[0120] Afterwards, if Figure 4C As shown in FIG. 1 , a metal film 410 is formed in the through hole 50a by a method described later, and further, first and second coating layers 411 and 412 are formed on the metal film 410 to form the mother substrate 100. The metal film 410 and the first and second coating layers 411 and 412 constitute the external terminals 41 to 44 before cutting. Figure 4DAs shown in the figure, the mother substrate 100, that is, the plurality of sealed inductor wirings 21, 22, is singulated along the cutting line C for every two inductor wirings 21, 22 using a dicing blade or the like, thereby manufacturing a plurality of inductor components 1. The metal film 410 and the first and second covering layers 411, 412 are cut along the cutting line C to form the external terminals 41 to 44. It should be noted that the method for manufacturing the external terminals 41 to 44 may be a method of cutting the metal film 410 and the first and second covering layers 411, 412 as described above, or a method of removing the insulating film 50 so as to form the through hole 50a in the shape of the external terminals 41 to 44 before forming the metal film 410 and the first and second covering layers 411, 412.

[0121] (Method of Manufacturing Metal Film 410)

[0122] A method for manufacturing the above-mentioned metal film 410 will be described.

[0123] A metal film 410 having conductivity and in contact with the base body 10 is formed by chemical plating on the end faces of the columnar wirings 31 to 34 and the upper surface of the base body 10. At this time, the plating conditions are controlled so that the thickness T1 of the first region 410a is smaller than the thickness T2 of the second region 410b. The metal film 410 is, for example, a layer containing Cu.

[0124] Specifically, the metal film 410 including Cu is deposited on the metal magnetic powder 136 including Fe by chemical plating.

[0125] To describe in detail, the metal magnetic powder 136 exposed on the upper surface 12a of the second magnetic layer 12 in contact with the metal film 410 functions as a catalyst. The metal (e.g., Fe) contained in the metal magnetic powder 136 undergoes a substitution reaction with the metal (e.g., Cu) used to form the metal film 410. As a result, the metal film 410 is formed on the metal magnetic powder 136.

[0126] Thereafter, the metal film 410 precipitated on the metal magnetic powder 136 grows, and the metal film 410 is also formed on the resin 135 of the second magnetic layer 12. Thereafter, the reducing agent contained in the plating solution decomposes to release electrons, which are supplied to the Cu ions in the plating solution to cause a reduction reaction.

[0127] In the chemical plating treatment, for example, formaldehyde can be preferably used as a reducing agent. In addition, the above-mentioned plating solution can also contain a complexing agent such as Rochelle salt or ethylenediaminetetraacetic acid (EDTA). It should be noted that in the method disclosed herein, before using the plating solution for plating, a plating pretreatment solution can be used to perform a plating pretreatment. The above-mentioned plating pretreatment solution may not contain a catalyst (such as a Sn-Pd catalyst, etc.).

[0128] In order to form the metal film 410 on the pillar-shaped wirings (Cu) 31 to 34, for example, the metal film 410 precipitated on the metal magnetic powder 136 may be grown and extended on the pillar-shaped wirings 31 to 34. Alternatively, a Pd layer may be formed on the pillar-shaped wirings 31 to 34 as a catalyst layer, and the metal film 410 may be formed on the catalyst layer by chemical plating.

[0129] (Method for Manufacturing First Covering Layer 411)

[0130] The first coating layer 411 is not particularly limited, and can be formed by, for example, plating. The first coating layer 411 is formed by, for example, a substitution reaction with the metal film 410 .

[0131] (Method for Manufacturing Second Covering Layer 412)

[0132] The second coating layer 412 is not particularly limited, and can be formed by, for example, plating. The second coating layer 412 is formed by, for example, a substitution reaction with the first coating layer 411.

[0133] (Second embodiment)

[0134] Figure 5 This is a partial enlarged view of the second magnetic layer 12 and the metal film 410A in the electronic component 1A of the second embodiment. The height of the end surface of the columnar wiring 31 to 34 relative to the upper surface of the second magnetic layer 12 is different between the second embodiment and the first embodiment. The difference is described below. The other configurations are the same as those of the first embodiment, and the same reference numerals as those of the first embodiment are marked, and their description is omitted.

[0135] like Figure 5 As shown, unlike the first embodiment in which the first main surface 10a of the blank 10 has a flat structure, the second embodiment has a concave structure. Figure 5 In, with Figure 2 Likewise, the coating layers 411 and 412 are omitted.

[0136] The end surface 31a of the first columnar wiring 31A is lower than the first main surface 10a which is the outer surface of the second magnetic layer 12. Therefore, the outer surface of the second magnetic layer 12 has a recessed portion at a position corresponding to the end surface of the first columnar wiring 31A. The metal film 410A is configured to fit into the recessed portion, so the metal film 410A is more firmly connected to the outer surface of the second magnetic layer 12 than when the end surface of the first columnar wiring 31A is flush with the outer surface of the second magnetic layer 12.

[0137] It should be noted that the present disclosure is not limited to the above-described embodiments, and design changes may be made within a scope that does not depart from the gist of the present disclosure.

[0138] In the above embodiment, two inductor elements, namely the first inductor element and the second inductor element, are arranged in the body. However, three or more inductor elements may be arranged. In this case, the number of external terminals and columnar wirings may be six or more, respectively.

[0139] In the above embodiment, the number of turns of the inductor wiring included in the inductor element is less than one turn, but the number of turns of the inductor wiring may be a curve with more than one turn. In addition, the total number of inductor wiring included in the inductor element is not limited to one layer, and may be a multilayer structure of two or more layers. In addition, the first inductor wiring of the first inductor element and the second inductor wiring of the second inductor element are not limited to the structure arranged on the same plane parallel to the first main surface, and may be a structure in which the first inductor wiring and the second inductor wiring are arranged in a direction orthogonal to the first main surface.

[0140] The "inductor wiring" is a wiring that generates magnetic flux in the magnetic layer when current flows, thereby providing inductance to the inductor component, and its structure, shape, material, etc. are not particularly limited. For example, various known wiring shapes such as zigzag wiring can be used.

[0141] In the above embodiment, the metal film 410 and the first coating layer 411 are used as external terminals of the inductor component, but are not limited thereto. For example, these metal films may also be internal electrodes of the inductor component. In addition, these metal films are not limited to inductor components, but may also be applied to other electronic components such as capacitor components and resistor components, and may also be used in circuit substrates carrying these electronic components. For example, these metal films may also be wiring patterns of circuit substrates.

[0142] In the above embodiment, the metal film 410 and the first coating layer 411 are used for external terminals, but they can also be used for inductor wiring. That is, the composite body can be used instead of the substrate, and the inductor wiring can be formed in the form of a metal film on the composite body by chemical plating. In this way, a metal film having the above-mentioned effect as an inductor wiring can be obtained, and a metal film can be formed as the above-mentioned effect.

[0143] In the above embodiment, the first to fourth columnar wirings 31 to 34 having end faces on the main surface 10a of the body 10 are used as internal electrodes, but the present invention is not limited thereto. That is, wirings having end faces on the first and second side faces 10b and 10c of the body 10 may also be used. In this case, the electronic component 1 has external terminals 41 to 44 at least on the first and second side faces 10b and 10c of the body 10.

Claims

1. An electronic component comprising: The composite body is composed of a composite material of resin and metal magnetic powder. an internal electrode disposed in the composite body and having an end surface exposed from an outer surface of the composite body, and a metal film disposed on the outer surface of the composite body and on the end surface of the internal electrode; The metal film has a first region and a second region, the first region being arranged on the end surface of the internal electrode, and the second region being arranged on the outer surface of the composite body in contact with the metal magnetic powder exposed on the outer surface. The thickness of the first region is smaller than the thickness of the second region, The metal film has a recessed portion on the end surface of the internal electrode, and the first region includes a portion of a bottom surface of the recessed portion. The exposed surface of the metal magnetic powder exposed from the composite is flat.

2. The electronic component according to claim 1, wherein A coating layer covering the metal film is further provided.

3. The electronic component according to claim 2, wherein: The coating layer includes a first coating layer covering the metal film, The first coating layer is made of Ni.

4. The electronic component according to claim 3, wherein The coating layer further includes a second coating layer covering the first coating layer, The second covering layer is made of Au.

5. The electronic component according to any one of claims 2 to 4, wherein The metal film is composed of Cu, In the second region, the thickness of the metal film is greater than the thickness of the coating layer.

6. The electronic component according to any one of claims 1 to 4, wherein The end surface of the internal electrode is lower than the outer surface of the composite body.

7. The electronic component according to any one of claims 1 to 4, wherein The metal magnetic powder includes Fe-based magnetic powder.

8. The electronic component according to any one of claims 1 to 4, wherein further comprising an inductor wiring disposed in the complex, The metal film constitutes at least a portion of an external terminal, and the external terminal is electrically connected to the inductor wiring through the internal electrode.

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