electronic components

Abstract

An electronic component includes a main body portion comprising alternately stacked insulating layers and conductive layers. Portions of the insulating layers and conductive layers are exposed on side surfaces perpendicular to the stacking direction of the main body portion. A metal film is provided on the side surfaces of the main body portion, extending in the stacking direction and covering the insulating layers and conductive layers exposed on the side surfaces.

Description

[0001] This application is a divisional application of an application filed on January 4, 2017, with application number 201780029556.5 (International Application Number: PCT / JP2017 / 000045), and with the title “Electronic Component”. Technical Field

[0002] The present invention relates to electronic components. Background Art

[0003] A coil component, as an example of an electronic component, is described in Japanese Patent Application Laid-Open No. 2014-197590 (Patent Document 1). This electronic component comprises: a substrate; a first conductive layer disposed on the upper surface of the substrate; a first insulating layer disposed on the first conductive layer; a second conductive layer disposed on the lower surface of the substrate; and a second insulating layer disposed below the second conductive layer. A first external electrode and a second external electrode are disposed on the first insulating layer. The first external electrode is electrically connected to the first conductive layer via a first lead-out electrode. The second external electrode is electrically connected to the second conductive layer via a second lead-out electrode.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-197590

[0005] However, in the above-mentioned conventional coil components, conductor layers are provided on both sides of the substrate. However, for the purpose of reducing height, for example, a structure in which multiple conductor layers and multiple insulating layers are alternately provided on the substrate, and the conductor layers are connected by via electrodes (a laminated structure) can also be considered. In this case, the insulating layer between the conductor layers has a higher thermal expansion coefficient than the conductor layer, resulting in a difference in expansion rate caused by heat, which can cause delamination between the conductor layers, such as at the interface between the conductor layer and the via electrode. Summary of the Invention

[0006] Therefore, an object of the present invention is to provide an electronic component capable of reducing delamination between conductive layers.

[0007] In order to solve the above problems, the electronic component of the present invention

[0008] It comprises: a main body including insulating layers and conductive layers alternately stacked,

[0009] Parts of the insulating layer and the conductive layer are exposed on the side surface in a direction perpendicular to the stacking direction of the main body.

[0010] A metal film is provided on the side surface of the main body portion, extending in a stacking direction and covering the insulating layer and the conductive layer exposed on the side surface.

[0011] Here, exposure includes not only exposure to the outside of the electronic component but also exposure to other components, in other words, exposure at the interface between the electronic component and other components. Covering includes covering at least a portion of the component.

[0012] In the electronic component described above, the metal film extends along the stacking direction of the insulating layer and the conductive layer, covering the insulating layer and the conductive layer on the side surface of the main body. Therefore, the metal film restricts movement of the insulating layer and the conductive layer in the stacking direction. Therefore, even when heat is applied to the electronic component, delamination between the conductive layers caused by the difference in thermal expansion coefficient between the insulating layer and the conductive layer can be reduced.

[0013] In one embodiment of the electronic component, the electronic component includes an external electrode provided on one surface of the main body in the stacking direction and electrically connected to the conductive layer, and the metal film is connected to the external electrode.

[0014] According to the above embodiment, the metal film is connected to the external electrode and covers the insulating layer and the conductive layer on the side surface of the main body. Therefore, the metal film electrically bypasses the external electrode and the conductive layer. Therefore, the resistance (particularly the DC resistance Rdc) between the external electrode and the conductive layer can be reduced.

[0015] In addition, in one embodiment of the electronic component,

[0016] The main body has a columnar electrode, which is located between the external electrode and the conductor layer and electrically connects the external electrode and the conductor layer.

[0017] Parts of the columnar electrodes are exposed on the side surfaces and the one surface of the main body, and the metal film covers the columnar electrodes exposed on the side surfaces.

[0018] According to the above embodiment, a portion of the columnar electrode is exposed on the side surface and one side of the main body, and the metal film covers the columnar electrode exposed on the side surface and one side. Here, in the manufacturing process of the electronic component, when cutting is performed at the side surface (cutting surface) of the main body, the load for cutting the columnar electrode on the side surface side of the main body becomes larger. If the load on the columnar electrode increases, there is a concern that the columnar electrode will peel off from the conductor layer and the resistance between layers will increase. However, the metal film covers the columnar electrode, so it is possible to enhance the peeling of the columnar electrode and reduce the resistance between layers.

[0019] In addition, in one embodiment of the electronic component,

[0020] The main body has a via hole electrode, which is embedded in the insulating layer and electrically connected to the conductor layer.

[0021] Part of the via hole electrode is exposed on the side surface of the main body portion, and the metal film covers the via hole electrode exposed on the side surface.

[0022] According to the above embodiment, a portion of the via electrode is exposed on the side surface of the main body, and the metal film covers the exposed portion of the via electrode. This allows the via electrode to be partially connected to the metal film, reducing thermally induced delamination between the conductor layer and the via electrode. This can be particularly effective in reducing delamination, even when the electronic component is small and the via electrode is further reduced in size.

[0023] In one embodiment of the electronic component, a width of one side of the via hole electrode in the stacking direction is smaller than a width of the other side of the via hole electrode in the stacking direction.

[0024] According to the above embodiment, the width of one side of the via hole electrode in the stacking direction is smaller than the width of the other side of the via hole electrode in the stacking direction. In this case, delamination is more likely to occur at the connection surface of the via hole electrode on one side connected to the conductor layer, thereby effectively reducing delamination caused by the metal film.

[0025] In addition, in one embodiment of the electronic component,

[0026] There are a plurality of the conductor layers exposed on the side surface in the stacking direction.

[0027] The main body has a via electrode that connects the conductor layers adjacent to each other in the stacking direction.

[0028] The metal film connects the conductor layers adjacent to each other in the stacking direction.

[0029] According to the above embodiment, the via hole electrode is usually small, so the area of ​​the connection surface between the conductor layer and the via hole electrode is also smaller. Therefore, interlayer peeling at the contact surface is easily caused by thermal expansion of the insulating layer, but the metal film will connect the adjacent conductor layers in the stacking direction, so the interlayer peeling between the conductor layer and the via hole electrode caused by heat can be reduced.

[0030] In one embodiment of the electronic component, the number of the conductive layers exposed on the side surface is three or more in a stacking direction.

[0031] According to the above embodiment, when there are three or more conductive layers, interlayer delamination is more likely to occur. However, the use of the metal film can more effectively reduce the effect of interlayer delamination.

[0032] In one embodiment of the electronic component, a plurality of the external electrodes are arranged in parallel on the one surface of the main body, a plurality of the metal films are arranged in parallel on the side surface of the main body, and each external electrode is connected to each metal film.

[0033] According to the above embodiment, multiple external electrodes are arranged in parallel on one surface of the main body, and multiple metal films are arranged in parallel on the side surface of the main body, with each external electrode connected to each metal film. Increasing the number of external electrodes and metal films in this manner imposes limitations on the size of the electronic component. Consequently, the connection surface between the conductor layer and other components becomes smaller, making interlayer delamination more likely to occur. This effectively reduces interlayer delamination caused by the metal films.

[0034] In one embodiment of the electronic component, the conductive layer forms a spiral wiring.

[0035] According to the above embodiment, the conductor layer forms narrow wiring, so the connection surface between the conductor layer and other components is easily reduced, which makes interlayer delamination more likely to occur. Therefore, the effect of reducing interlayer delamination caused by the metal film is more effective.

[0036] According to the electronic component of the above aspect, the metal film extending in the stacking direction and covering the insulating layer and the conductive layer exposed on the side surface is provided on the side surface of the main body portion, thereby reducing interlayer delamination of the conductive layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a perspective view showing a first embodiment of the electronic component.

[0038] Figure 2 This is an XZ cross-sectional view of an electronic component.

[0039] Figure 3A These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0040] Figure 3B These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0041] Figure 3C These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0042] Figure 3D These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0043] Figure 3E These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0044] Figure 3F These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0045] Figure 3G These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0046] Figure 3H These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0047] Figure 3I These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0048] Figure 3J These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0049] Figure 3K These are explanatory diagrams for explaining a method for manufacturing an electronic component.

[0050] Figure 4 This is a view taken along the X-direction showing the second embodiment of the electronic component.

[0051] Figure 5 It is a perspective view showing a third embodiment of the electronic component.

[0052] Figure 6A This is a graph showing the relationship between the number of reflow cycles and resistance in Examples.

[0053] Figure 6B This is a graph showing the relationship between the number of reflow cycles and resistance in a comparative example. DETAILED DESCRIPTION

[0054] Hereinafter, one aspect of the present invention will be described in detail based on the illustrated embodiment.

[0055] (First embodiment)

[0056] Figure 1 It is a perspective view showing a first embodiment of the electronic component. Figure 2 This is an XZ cross-sectional view of an electronic component. Figure 1 and Figure 2 A coil component 1 is shown as an example of an electronic component. The coil component 1 is mounted on electronic devices such as personal computers, DVD players, digital cameras, TVs, mobile phones, and automotive electronics, and is, for example, a component having an overall rectangular parallelepiped shape. However, the shape of the coil component 1 is not particularly limited, and may also be cylindrical, polygonal, truncated, or polygonal.

[0057] like Figure 1 and Figure 2As shown, coil component 1 includes: a main body 10 comprising alternately stacked insulating layers 41, 42, 43 and conductive layers 201, 202; and external electrodes 61, 62 disposed on one surface 103 of main body 10 in the stacking direction and electrically connected to conductive layers 201, 202. Here, the stacking direction is not the direction in which insulating layers 41, 42, 43 and conductive layers 201, 202 extend (the XY direction), but rather the direction in which they are stacked (the Z direction). In other words, first insulating layer 41, first conductive layer 201, second insulating layer 42, second conductive layer 202, and third insulating layer 43 are stacked in this order along the stacking direction.

[0058] Parts of the insulating layers 41, 42, 43 and the conductive layers 201, 202 are exposed on the side surfaces 101, 102 of the main body 10 in a direction perpendicular to the stacking direction. A metal film 80 is provided on the side surfaces 101, 102 of the main body 10. The metal film 80 is connected to the external electrodes 61, 62 and extends along the stacking direction to cover the insulating layers 41, 42, 43 and the conductive layers 201, 202 exposed on the side surfaces 101, 102. Figure 1 In FIG. 8 , for easy understanding, the external electrodes 61 and 62 are omitted, and the metal film 80 is depicted with a two-dot chain line.

[0059] Therefore, the metal film 80 extends along the stacking direction of the insulating layers 41, 42, 43 and the conductive layers 201, 202, covering the insulating layers 41, 42, 43 and the conductive layers 201, 202 at the side surfaces 101, 102 of the main body 10. Thus, the metal film 80 restricts the movement of the insulating layers 41, 42, 43 and the conductive layers 201, 202 in the stacking direction. Therefore, even when heat is applied to the coil component 1, delamination between the conductive layers 201, 202 caused by the difference in thermal expansion coefficients between the insulating layers 41, 42, 43 and the conductive layers 201, 202 can be reduced. Furthermore, even if a conductive resin containing metal powder is used instead of the metal film 80, the conductive resin has a thermal expansion coefficient close to that of the insulating layers 41, 42, 43 and cannot restrict the expansion and contraction of the insulating layers 41, 42, 43, thus failing to reduce delamination between the layers.

[0060] Furthermore, the metal film 80 is connected to the external electrodes 61 and 62 and covers the insulating layers 41, 42, and 43 and the conductive layers 201 and 202 on the side surfaces 101 and 102 of the main body 10. Thus, the metal film 80 electrically bypasses the external electrodes 61 and 62 and the conductive layers 201 and 202. Consequently, the resistance (particularly the DC resistance Rdc) between the external electrodes 61 and 62 and the conductive layers 201 and 202 can be reduced.

[0061] Furthermore, when the external electrodes 61 and 62 of the coil component 1 are mounted on the mounting substrate using solder, the solder is transferred onto the metal film 80 and wetted in a direction away from the external electrodes 61 and 62 in the stacking direction, forming a rounded shape, thereby improving the strength of the coil component 1. This improves the reliability of the solder connection and, for example, can prevent the formation of cracks in the solder due to heat such as reflow.

[0062] Furthermore, in the coil component 1 described above, the main body 10 includes columnar electrodes 11 and 12. These columnar electrodes 11 and 12 are located between the external electrodes 61 and 62 and the conductive layers 201 and 202, electrically connecting the external electrodes 61 and 62 to the conductive layers 201 and 202. Parts of the columnar electrodes 11 and 12 are exposed on the side surfaces 101 and 102 and one surface 103 of the main body 10. The metal film 80 covers the columnar electrodes 11 and 12 exposed on the side surfaces 101 and 102.

[0063] Here, during the manufacturing process of coil component 1, when cutting at side surfaces 101 and 102 (cutting surfaces) of main body 10, the load applied to columnar electrodes 11 and 12 on the side surfaces 101 and 102 of main body 10 increases. If the load on columnar electrodes 11 and 12 increases, there is a concern that columnar electrodes 11 and 12 may peel off from conductive layers 201 and 202, and the interlayer resistance may increase. However, since metal film 80 covers columnar electrodes 11 and 12, it can reinforce the peeling of columnar electrodes 11 and 12 and reduce the interlayer resistance.

[0064] Furthermore, in the coil component 1, the main body 10 includes via electrodes 271, 272, and 273 that are embedded in the insulating layers 42 and 43 and electrically connect the conductive layers 201 and 202. Via electrodes 271 and 272 are partially exposed on the side surfaces 101 and 102 of the main body 10, and the metal film 80 covers the exposed via electrodes 271 and 272 on the side surfaces 101 and 102.

[0065] Thus, connecting via electrodes 271, 272 to metal film 80 can reduce thermal delamination between conductor layers 201, 202 and via electrodes 271, 272. Particularly, as coil component 1 is made smaller, further miniaturization of via electrodes 271, 272 can effectively reduce delamination.

[0066] Hereinafter, the coil component 1 will be described in detail.

[0067] like Figure 1 and Figure 2As shown, the coil component 1 has: a main body 10; a first external electrode 61 and a second external electrode 62 arranged on a surface 103 of the main body 10; a metal film 80 arranged on the first side surface 101 and the second side surface 102 of the main body 10; and a first columnar electrode 11 arranged on the main body 10 and connected to the first external electrode 61 and a second columnar electrode 12 connected to the second external electrode 62.

[0068] The main body 10 is formed in a generally rectangular parallelepiped shape and has a length, a width, and a height. The length direction of the main body 10 is the X direction, the width direction of the main body 10 is the Y direction, and the height direction of the main body 10 is the Z direction. The first side surface 101 and the second side surface 102 are located in the X direction.

[0069] The main body 10 includes: a first conductor layer 201 and a second conductor layer 202; an insulator 40 covering the first and second conductor layers 201 and 202; and a magnetic body 30 covering the insulator 40. The insulator 40 is composed of a first insulating layer 41, a second insulating layer 42, and a third insulating layer 43. The first insulating layer 41, the first conductor layer 201, the second insulating layer 42, the second conductor layer 202, and the third insulating layer 43 are stacked in order from the bottom layer to the top layer. In addition, in this specification, the upper and lower parts of the coil component 1 are described as the same as Figure 1 The Z direction is consistent with the direction in which the layers are stacked (stacking direction).

[0070] The first conductor layer 201 includes a first spiral wiring 21. The second conductor layer 202 includes a second spiral wiring 22. The first and second spiral wirings 21 and 22 are each formed in a spiral shape on a plane. The first spiral wiring 21 is formed, for example, in a spiral shape that rotates clockwise while approaching the center when viewed from above. The second spiral wiring 22 is formed, for example, in a spiral shape that rotates clockwise while moving away from the center when viewed from above.

[0071] The first and second spiral wirings 21 and 22 are made of a low-resistance metal such as Cu, Ag, or Au. Preferably, Cu plating formed by a semi-additive process is used to form spiral wirings with low resistance and a narrow pitch.

[0072] First spiral wiring 21 is stacked on first insulating layer 41. Second insulating layer 42 is stacked on first insulating layer 41 and covers first spiral wiring 21. Second spiral wiring 22 is stacked on second insulating layer 42. Third insulating layer 43 is stacked on second insulating layer 42 and covers second spiral wiring 22. In this way, first and second spiral wirings 21 and 22 and first to third insulating layers 41, 42, and 43 are stacked alternately. In other words, first and second spiral wirings 21 and 22 are stacked on insulating layers and covered by insulating layers above them.

[0073] The second spiral wiring 22 is electrically connected to the first spiral wiring 21 via a third via electrode 273 extending on the inner circumference in the stacking direction. The third via electrode 273 is provided within the second insulating layer 42. The inner circumference 21a of the first spiral wiring 21 and the inner circumference 22a of the second spiral wiring 22 are electrically connected via the third via electrode 273. Thus, the first spiral wiring 21 and the second spiral wiring 22 form an inductor.

[0074] When viewed in the stacking direction, the outer peripheral portion 21b of the first spiral wiring 21 and the outer peripheral portion 22b of the second spiral wiring 22 are located at both ends of the insulator 40. The outer peripheral portion 21b of the first spiral wiring 21 is located on the first columnar electrode 11 side, and the outer peripheral portion 22b of the second spiral wiring 22 is located on the second columnar electrode 12 side.

[0075] The outer peripheral portion 21 b of the first spiral wiring 21 is electrically connected to the first columnar electrode 11 via the second via hole electrode 272 provided on the outer peripheral side of the second insulating layer 42 , the first connecting wiring 25 provided on the second insulating layer 42 , and the first via hole electrode 271 provided on the outer peripheral side of the third insulating layer 43 .

[0076] The outer peripheral portion 22b of the second spiral wiring 22 is electrically connected to the second columnar electrode 12 via a first via electrode 271 provided in the third insulating layer 43. Furthermore, the outer peripheral portion 22b of the second spiral wiring 22 is also electrically connected to the second connecting wiring 26 provided on the first insulating layer 41 via a second via electrode 272 provided in the second insulating layer 42, but this structure is not required. However, by providing the second connecting wiring 26 and connecting it to the outer peripheral portion 22b, the symmetry within the coil component 1 can be improved, thereby reducing differences in electrical characteristics and reliability.

[0077] Here, the second connecting wiring 26 and the first spiral wiring 21 constitute the first conductor layer 201, and the first connecting wiring 25 and the second spiral wiring 22 constitute the second conductor layer 202. However, in the first conductor layer 201, the second connecting wiring 26 and the first spiral wiring 21 are not electrically connected, and in the second conductor layer 202, the first connecting wiring 25 and the second spiral wiring 22 are not electrically connected.

[0078] The insulator 40 is made of a composite material of an inorganic filler and a resin. The resin is, for example, an organic insulating material made of epoxy resin, bismaleimide, liquid crystal polymer, polyimide, etc. The inorganic filler is an insulating layer such as SiO2. In addition, the insulator 40 is not limited to a composite material and can also be made of resin alone. The thermal expansion coefficient of the insulator 40 (the first, second, and third insulating layers 41, 42, and 43) is usually above 30 ppm / k, but in this case, the metal film 80 can also effectively reduce interlayer delamination. The insulator 40 has a radially inner hole portion 40a on the inner side of the radial inner side of the first and second spiral wirings 21 and 22.

[0079] Magnetic body 30 is composed of a composite material of resin 35 and metal magnetic powder 36. Resin 35 is an organic insulating material such as epoxy resin, bismaleimide, liquid crystal polymer, or polyimide. Metal magnetic powder 36 is, for example, an FeSi alloy such as FeSiCr, an FeCo alloy, an Fe alloy such as NiFe, or an amorphous alloy thereof.

[0080] The magnetic body 30 has an inner magnetic circuit 37a and an outer magnetic circuit 37b. The inner magnetic circuit 37a is located radially inward of the first and second spiral wirings 21 and 22 and the radially inner hole 40a of the insulator 40. The outer magnetic circuit 37b is located above and below the first and second spiral wirings 21 and 22 and the insulator 40, and is also located radially outward of the insulator 40 (not shown).

[0081] First and second columnar electrodes 11 and 12 are disposed above the first and second spiral wirings 21 and 22 in the stacking direction. First columnar electrode 11 is located on the first side surface 101 side of main body 10. Second columnar electrode 12 is located on the second side surface 102 side of main body 10. Columnar electrodes 11 and 12 are formed, for example, from the same material as spiral wirings 21 and 22.

[0082] The first columnar electrode 11 is embedded in the magnetic body 30 of the main body 10, with portions of the first columnar electrode 11 exposed on a first side surface 101 and a first surface 103 of the main body 10. The second columnar electrode 12 is embedded in the magnetic body 30 of the main body 10, with portions of the second columnar electrode 12 exposed on a second side surface 102 and a first surface 103 of the main body 10.

[0083] The first columnar electrode 11 is electrically connected to the first spiral wiring 21, and the second columnar electrode 12 is electrically connected to the second spiral wiring 22. A first external electrode 61 is provided on the upper surface of the first columnar electrode 11, and a second external electrode 62 is provided on the upper surface of the second columnar electrode 12. The first and second external electrodes 61 and 62 are connected to electrodes on the mounting substrate via solder when the coil component 1 is mounted on the mounting substrate.

[0084] The metal film 80 contacts the first columnar electrode 11, the first via electrode 271, the first connecting wiring 25, the second via electrode 272, and the outer peripheral portion 21b of the first spiral wiring 21 on the first side surface 101 of the main body 10, and also contacts the first external electrode 61. The metal film 80 is composed of a low-resistance metal such as Cu, Ag, or Au. The metal film 80 is formed, for example, by electrolytic plating, chemical plating, or sputtering.

[0085] Likewise, the metal film 80 contacts the second columnar electrode 12 , the first via electrode 271 , the outer peripheral portion 22 b of the second spiral wiring 22 , the second via electrode 272 , and the second connecting wiring 26 at the second side surface 102 of the main body 10 , and contacts the second external electrode 62 .

[0086] Next, use Figures 3A to 3K A method for manufacturing the coil component 1 will be described.

[0087] like Figure 3A As shown, a base 50 is prepared. In this embodiment, a plurality of coil components 1 are manufactured using one base 50. The base 50 includes an insulating substrate 51 and a base metal layer 52 provided on both sides of the insulating substrate 51. In this embodiment, the insulating substrate 51 is a glass epoxy substrate, and the base metal layer 52 is a Cu foil with a smooth upper surface. By peeling off the base 50 as described later, the thickness of the base 50 does not affect the thickness of the coil component 1. Therefore, a thickness that is easy to handle appropriately can be used for reasons such as warping during processing.

[0088] Moreover, if Figure 3B As shown, a dummy metal layer 60 is bonded to one surface of the base 50. In this embodiment, the dummy metal layer 60 is a Cu foil. The dummy metal layer 60 is bonded to the base metal layer 52 of the base 50, and thus the dummy metal layer 60 is bonded to the smooth surface of the base metal layer 52. This weakens the adhesion between the dummy metal layer 60 and the base metal layer 52, making it easier to peel the base 50 from the dummy metal layer 60 in a later step. The adhesive bonding the base 50 and the dummy metal layer 60 is preferably a low-viscosity adhesive. In addition, to weaken the adhesion between the base 50 and the dummy metal layer 60, the bonding surface of the base 50 and the dummy metal layer 60 is preferably a glossy surface.

[0089] Next, the first insulating layer 41 is laminated onto the dummy metal layer 60 temporarily secured to the base 50. At this point, the first insulating layer 41 is heat-pressed and thermally cured using a vacuum laminator, a press, or the like. Subsequently, the central portion of the first insulating layer 41, corresponding to the inner magnetic circuit (magnetic core), is removed using a laser or the like to form an opening 41a.

[0090] Moreover, if Figure 3CAs shown, on the first insulating layer 41, a first spiral wiring 21 and a second connecting wiring 26 are stacked as the first conductor layer 201 using a semi-additive process. The first spiral wiring 21 and the second connecting wiring 26 are formed in a manner that does not contact each other. The second connecting wiring 26 is arranged on the side opposite to the outer peripheral portion 21b. In detail, first, a power supply film is formed on the first insulating layer 41 by chemical plating, sputtering, evaporation, etc. After the power supply film is formed, a photosensitive resist is coated and attached to the power supply film, and a wiring pattern is formed by photolithography. Thereafter, metal wiring equivalent to the first spiral wiring 21 and the second connecting wiring 26 is formed by electrolytic plating. After the metal wiring is formed, the photosensitive resist is peeled off and removed using a chemical solution, and the power supply film is etched away. In addition, thereafter, the metal wiring can be used as a power supply portion, and wiring 21 and 26 in a narrow space can be obtained by performing additional Cu electrolytic plating. Furthermore, a first sacrificial conductor 71 corresponding to the internal magnetic circuit is provided on the dummy metal layer 60 within the opening 41 a of the first insulating layer 41 using a semi-additive process.

[0091] Moreover, if Figure 3D As shown, the second insulating layer 42 is stacked on the first insulating layer 41 to cover the first spiral wiring 21, the second connecting wiring 26, and the first sacrificial conductor 71. The second insulating layer 42 is then heat-pressed and thermally cured using a vacuum laminator or a press.

[0092] Moreover, if Figure 3E As shown, via holes 42b for filling second and third via hole electrodes 272 and 273 are formed in second insulating layer 42 by laser processing or the like. Furthermore, a portion of second insulating layer 42 corresponding to the inner magnetic path (core) is removed by laser processing or the like to form opening 42a.

[0093] Moreover, if Figure 3F As shown, the second and third via-hole electrodes 272 and 273 are filled in the via holes, and the second spiral wiring 22 and the first connecting wiring 25, serving as the second conductor layer 202, are stacked on the second insulating layer 42. The second spiral wiring 22 and the first connecting wiring 25 are formed so as not to contact each other. The first connecting wiring 25 is provided on the side opposite to the outer peripheral portion 22b. Furthermore, a second sacrificial conductor 72 corresponding to the inner magnetic circuit is provided on the first sacrificial conductor 71 within the opening 42a of the second insulating layer 42. In this case, the second and third via-hole electrodes 272, 273, the second spiral wiring 22, the first connecting wiring 25, and the second sacrificial conductor 72 can be provided using the same process as the first spiral wiring 21, the second connecting wiring 26, and the first sacrificial conductor 71.

[0094] Moreover, if Figure 3GAs shown, the third insulating layer 43 is laminated on the second insulating layer 42 to cover the second spiral wiring 22, the first connecting wiring 25, and the second sacrificial conductor 72. The third insulating layer 43 is then heat-pressed and thermally cured using a vacuum laminator or a press.

[0095] Moreover, if Figure 3H As shown, a portion of the third insulating layer 43 corresponding to the inner magnetic path (magnetic core) is removed by laser or the like to form an opening 43a.

[0096] Thereafter, the base 50 is peeled off from the dummy metal layer 60 at the bonding surface between one surface of the base 50 (base metal layer 52) and the dummy metal layer 60. Then, the dummy metal layer 60 is removed by etching or the like. At this time, the first and second sacrificial conductors 71 and 72 are removed by etching or the like, as shown in FIG. Figure 3I As shown, a radially inner hole 40a corresponding to the inner magnetic circuit is provided in the insulator 40. Subsequently, a through hole 43b for receiving the first via electrode 271 is formed in the third insulating layer 43 using laser processing or other methods. Furthermore, the first via electrode 271 is filled in the through hole 43b, and the first and second columnar electrodes 11 and 12 are stacked on the third insulating layer 43. At this point, the first via electrode 271 and the first and second columnar electrodes 11 and 12 can be formed using the same process as the first spiral wiring 21.

[0097] Moreover, if Figure 3J As shown, the first and second columnar electrodes 11 and 12 and the upper and lower surfaces of the insulator 40 are covered with magnetic material 30. The magnetic material 30 is then heat-pressed and heat-cured using a vacuum laminator, a press, or the like, thereby forming the coil substrate 5. At this time, the magnetic material 30 also fills the hole 40a of the insulator 40.

[0098] Moreover, if Figure 3K As shown in FIG. 1 , the magnetic bodies 30 on the upper and lower sides of the coil substrate 5 are thinned by a grinding process. At this time, by partially exposing the first and second columnar electrodes 11 and 12, the upper surfaces of the first and second columnar electrodes 11 and 12 are located on the same plane as the upper surface of the magnetic body 30. Furthermore, the first and second external electrodes 61 and 62 (see FIG. 1 ) are provided on the upper surfaces of the first and second columnar electrodes 11 and 12. Figure 2 ).

[0099] Thereafter, the coil substrate 5 (main body 10) is singulated by cutting and scribing along the cut surfaces C. At this point, the cut surfaces C constitute the first and second side surfaces 101 and 102 of the main body 10. In other words, the first columnar electrode 11, the first via electrode 271, the first connecting wiring 25, the second via electrode 272, and the outer peripheral portion 21b of the first spiral wiring 21 are exposed on the first side surface 101 of the main body 10. The second columnar electrode 12, the first via electrode 271, the outer peripheral portion 22b of the second spiral wiring 22, the second via electrode 272, and the second connecting wiring 26 are exposed on the second side surface 102 of the main body 10.

[0100] Then, a metal film 80 is provided on the first and second side surfaces 101 and 102 of the main body 10 (see Figure 2 ). The metal film 80 is formed by, for example, Cu plating. The plating process may also be any of chemical plating and electrolytic plating. Thus, on the first side surface 101, the metal film 80 covers the first external electrode 61, the first columnar electrode 11, the first via electrode 271, the first connecting wiring 25, the second via electrode 272, and the peripheral portion 21b of the first spiral wiring 21. On the second side surface 102, the metal film 80 covers the second external electrode 62, the second columnar electrode 12, the first via electrode 271, the peripheral portion 22b of the second spiral wiring 22, the second via electrode 272, and the second connecting wiring 26. In this way, a Figure 2 The coil component 1 is shown.

[0101] Furthermore, in the manufacturing method exemplified above, the coil substrate 5 is formed on one of the two surfaces of the base 50. However, the coil substrate 5 can also be formed on both surfaces of the base 50. Furthermore, it is also possible to form a plurality of coil substrates 5 simultaneously by forming a plurality of first and second spiral wirings 21 and 22, an insulator 40, and the like in parallel on one surface of the base 50 and then forming them as a single piece. This allows the simultaneous formation of a plurality of coil substrates 5 using a single base 50, thereby achieving higher productivity.

[0102] (Second embodiment)

[0103] Figure 4 This is an X-direction view showing a second embodiment of the electronic component of the present invention. The second embodiment differs from the first embodiment in the structure of the via electrodes. This difference is described below. In the second embodiment, reference numerals identical to those in the first embodiment indicate the same structures as in the first embodiment, and therefore their descriptions are omitted.

[0104] like Figure 4As shown, for the coil component 1A as an electronic component, the width of one side of the first via electrode 271A in the stacking direction is smaller than the width of the other side of the first via electrode 271A in the stacking direction. Specifically, the width of the lower end (the lower side in the Z direction) of the first via electrode 271A is smaller than the width of the upper end (the lower side in the Z direction) of the first via electrode 271A. In other words, when viewed from the X direction, the shape of the first via electrode 271A is trapezoidal. In this case, from the perspective of the contact area, interlayer delamination is likely to occur at the connection surface connected to the lower end side (one side) of the first via electrode 271A, that is, to the first connection wiring 25.

[0105] Therefore, this structure can more effectively reduce delamination of the metal film 80. The second via electrode 272A has the same structure as the first via electrode 271A. The second side surface 102 has the same structure as the first side surface 101.

[0106] Furthermore, the width of the upper end of the first via hole electrode may be smaller than the width of the lower end of the first via hole electrode. In addition, at least one of the first and second via hole electrodes may also have the above-mentioned structure.

[0107] (Third embodiment)

[0108] Figure 5 This is a perspective view of a third embodiment of the electronic component of the present invention. The third embodiment differs from the first embodiment in the number of external electrodes and metal films. This structural difference is described below. In the third embodiment, reference numerals identical to those in the first embodiment denote the same structures as in the first embodiment, and therefore their descriptions are omitted.

[0109] like Figure 5 As shown, in the coil component 1B as an electronic component, a plurality of first external electrodes 61 (four in this embodiment) are arranged side by side along the Y direction on one surface 103 of the main body 10. A plurality of metal films 80 (four in this embodiment) are arranged side by side along the Y direction on the first side surface 101 of the main body 10. Each first external electrode 61 is connected to each metal film 80.

[0110] Similarly, a plurality of second external electrodes 62 (four in this embodiment) are arranged side by side along the Y direction on one surface 103 of the main body 10. A plurality of metal films 80 (four in this embodiment) are arranged side by side along the Y direction on the second side surface 102 of the main body 10. Each second external electrode 62 is connected to each metal film 80.

[0111] In this way, if the number of the first and second external electrodes 61, 62 and the metal film 80 increases, there will be restrictions on the size of the coil component 1, so the columnar electrodes 11, 12, spiral wiring 21, 22, via-hole electrodes 271, 272, and connecting wiring 25, 26 become smaller.

[0112] However, as described in the first embodiment, the metal film 80 covers the columnar electrodes 11 and 12 , the spiral wirings 21 and 22 , the via electrodes 271 and 272 , and the connection wirings 25 and 26 , and thus can effectively reduce delamination between these layers.

[0113] The present invention is not limited to the above-described embodiment, and design changes can be made without departing from the spirit of the present invention. For example, the respective features of the first to third embodiments may be combined.

[0114] In the first embodiment, the metal film and the external electrodes are separate components, but the metal film and the external electrodes may be the same component (integrated). In addition, in the first embodiment, the columnar electrodes are provided, but the columnar electrodes may be omitted.

[0115] In the first embodiment described above, the pillar electrodes and via electrodes are exposed on the side surfaces. However, it is also possible to expose only the conductor layers on the side surfaces without exposing the pillar electrodes and via electrodes on the side surfaces. In this case, the metal film is formed by plating growth from the conductor layers on both sides of the insulating layer, spanning the insulating layers. As a result, the metal film covers the insulating layers between the conductor layers. In other words, the via electrodes can be covered by the insulating layers without exposing the via electrodes on the side surfaces of the main body. In this case, there are multiple conductor layers exposed on the side surfaces in the stacking direction, the main body includes via electrodes that connect adjacent conductor layers in the stacking direction, and the metal film forms a structure that connects adjacent conductor layers in the stacking direction. In the absence of a metal film, the via electrodes are typically smaller than the conductor layers, and the area of ​​the connection surface between the conductor layers and the via electrodes is also reduced. This makes it easier for delamination to occur at this contact surface due to thermal expansion of the insulating layer. On the other hand, in the above structure, the metal film connects adjacent conductor layers in the stacking direction, thereby limiting the thermal expansion and compression of the insulating layer between the conductor layers. Thus, even in a structure in which the via hole electrodes are not exposed on the side surface of the main body, that is, a structure in which the metal film and the via hole electrodes are not in contact with each other, delamination between the conductor layer and the via hole electrodes can be reduced.

[0116] In the second embodiment described above, the structure of the metal film, the columnar electrodes, and the trapezoidal via-hole electrodes has been described. However, the structure may also be the metal film and the trapezoidal via-hole electrodes alone.

[0117] In the third embodiment described above, the structure of the plurality of metal films, the plurality of external electrodes, the columnar electrodes, and the via-hole electrodes has been described. However, the structure may be simply the plurality of metal films and the plurality of external electrodes.

[0118] While the first embodiment described above includes a two-layer spiral wiring, a spiral wiring with three or more layers may also be used. In other words, while the conductor layer is two layers, it may also have three or more layers. If the conductor layer has three or more layers, the insulating layer is stacked multiple times, which increases thermal expansion and contraction, making interlayer delamination more likely. Therefore, the metal layer is more effective in reducing interlayer delamination. Furthermore, while the insulating layer has three layers, it may also have four or more layers.

[0119] In the first embodiment described above, the electronic component is a coil component, but it may also be a capacitor, etc. In the case of a coil component, the conductor layer forms a spiral wiring, that is, a narrow wiring. Therefore, the connection surface of the conductor layer to other components is easily reduced, which makes it easy for interlayer delamination to occur. Therefore, the effect of reducing interlayer delamination by using a metal film is more effective.

[0120] (Example)

[0121] Next, examples of the first embodiment will be described.

[0122] Figure 6A The relationship between the number of reflows and the DC resistance Rdc when the coil component is mounted on the mounting substrate via solder is shown for the example of the first embodiment. In addition, the DC resistance Rdc is measured as the DC resistance value (unit: Ω) between the external electrodes (between the external electrodes 61 and 62 of the coil component 1). Figure 6A As shown, in the embodiment, the DC resistance Rdc hardly changes before and after reflow.

[0123] Figure 6B The relationship between the number of reflows and the DC resistance Rdc is shown for the coil component without the metal film as a comparative example of the first embodiment. Figure 6A Same. Figure 6B As shown in FIG. 1 , in the comparative example, the DC resistance Rdc increases before and after reflow, which means that delamination between the conductor layers occurs due to heat during reflow.

[0124] Thus, the embodiment incorporating a metal film can reduce delamination between the conductor layers. Furthermore, the embodiment exhibits a lower pre-reflow DC resistance (Rdc) than the comparative example. This is believed to be because the embodiment forms a path between the external electrode and the conductor layer via the metal film. This path avoids the interface between the conductor layer and the via electrode, where DC resistance (Rdc) is likely to increase, resulting in a lower DC resistance (Rdc). Therefore, the structure of the embodiment also has the effect of reducing the DC resistance between the external electrode and the conductor layer.

[0125] Description of Reference Numerals

[0126] 1, 1A, 1B...coil component (electronic component); 10...main body; 101...first side surface; 102...second side surface; 103...one surface; 11...first columnar electrode; 12...second columnar electrode; 21...first spiral wiring; 21a...inner circumference; 21b...outer circumference; 22...second spiral wiring; 22a...inner circumference; 22b...outer circumference; 25...first connecting wiring; 26...second connecting wiring; 30...magnetic body; 40...insulator; 41...first insulating layer; 42...second insulating layer; 43...third insulating layer; 61...first external electrode; 62...second external electrode; 80...metal film; 201...first conductive layer; 202...second conductive layer; 271...first via electrode; 272...second via electrode; C...cut surface.

Claims

1. An electronic component, characterized in that have: a main body portion comprising a first end surface and a second end surface facing each other and an upper surface connecting the first end surface and the second end surface; a circuit element embedded in the body; a first connecting wiring embedded in the first end surface side of the main body and electrically connected to the circuit element; a columnar electrode, the columnar electrode being arranged apart from the first connection wiring in a first direction when viewed from a direction perpendicular to the first end surface, and being embedded in the main body so as to be partially exposed from the first end surface to the upper surface; as well as a first via hole electrode connecting the first connection wiring and the columnar electrode, embedded in the body portion and partially exposed from the first end surface; In terms of an exposed width on the first end surface along a second direction orthogonal to the first direction when viewed from a direction orthogonal to the first end surface, the exposed width of the first via electrode is smaller than the exposed width of the columnar electrode.

2. The electronic component according to claim 1, wherein There are multiple first via electrodes. A sum of the exposed widths of the plurality of first via electrodes is smaller than the exposed width of the columnar electrode.

3. The electronic component according to claim 2, wherein The exposed widths of the plurality of first via electrodes are the same as each other, The plurality of first via-hole electrodes are arranged at equal intervals along the second direction. The electronic component according to claim 1 , wherein have: a second connecting wiring embedded in the second end surface of the main body and provided on a side opposite to the first direction and separated from the first connecting wiring; a second via electrode connecting the outer periphery of the second spiral wiring in the circuit element and the second connection wiring; The exposed width of the second via electrode is smaller than the exposed width of the columnar electrode.

5. The electronic component according to claim 4, wherein There are multiple second via electrodes. A sum of the exposed widths of the plurality of second via electrodes is smaller than the exposed width of the pillar electrode. The electronic component according to claim 5 , wherein The exposed widths of the plurality of second via electrodes are the same as each other, The plurality of second via-hole electrodes are arranged at equal intervals along the second direction.

7. The electronic component according to claim 4, wherein The first via electrode and the second via electrode are not arranged along the first direction.

8. The electronic component according to claim 4, wherein Part of the first via hole electrode and part of the first connection wiring are exposed from the first end surface.

9. The electronic component according to claim 8, wherein Part of the second via hole electrode and part of the second connection wiring are exposed from the second end surface.

10. The electronic component according to claim 1, wherein The electronic component has: a second connecting wiring embedded in the second end surface of the main body and provided on the side opposite to the first direction and separated from the first connecting wiring; a second via electrode connecting the outer periphery of the second spiral wiring in the circuit element and the second connection wiring; The exposed width of the second via electrode is smaller than the exposed width of the columnar electrode. The exposed width of the second via electrode is 0. The electronic component according to claim 1 , wherein The circuit element is an inductor, The main body is composed of a magnetic body and an insulator. The columnar electrode is located in the magnetic body. The first connection wiring, the first via electrode, and the inductor are located within the insulator.

12. The electronic component according to claim 11, wherein Also features: a second connecting wiring embedded in the second end surface side of the main body and electrically connected to the circuit element; a second columnar electrode disposed apart from the first connection wiring in the first direction and embedded in the main body portion so as to be partially exposed from the second end surface to the upper surface; as well as a second via electrode connecting the outer periphery of the second spiral wiring in the circuit element and the second connection wiring; Regarding the second exposure width on the second end surface along the second direction, the second exposure width of the second via electrode on the second end surface side is smaller than the second exposure width of the second columnar electrode on the second end surface side.

13. The electronic component according to claim 12, wherein The first end of the inductor is electrically connected to the first connection wiring on the first end surface side. The second end of the inductor is electrically connected to the second connection wiring on the second end surface side.

14. The electronic component according to claim 4, wherein The circuit element is a stacked inductor composed of a plurality of spiral wirings formed in a spiral shape in a plane parallel to the upper surface. The main body is composed of a magnetic body and an insulator. The columnar electrode is located in the magnetic body. The first connecting wiring, the first via electrode, the second connecting wiring, the second via electrode, and the inductor are located within the insulator.

15. The electronic component according to claim 14, wherein Also features: a second columnar electrode disposed apart from the first connection wiring in the first direction and embedded in the main body portion so as to be partially exposed from the second end surface to the upper surface; a fourth via electrode connecting the outer periphery of the second spiral wiring in the circuit element and the second columnar electrode; In terms of the second exposure width on the second end face along the second direction, the second exposure width of the fourth conductive hole electrode on the second end face side and the second exposure width of the second conductive hole electrode on the second end face side are smaller than the second exposure width of the second columnar electrode on the second end face side.

16. The electronic component according to claim 15, wherein The first end of the inductor is electrically connected to the first connection wiring on the first end surface side. The second end of the inductor is electrically connected to the second connection wiring on the second end surface side.

17. A method for manufacturing an electronic component, wherein: have: The step of laminating insulating layers in a first direction to form a coil body; forming a circuit element and a first connection wiring electrically connected to the circuit element on the insulating layer; forming a first via electrode on the first connection wiring; forming a columnar electrode on the first via electrode so as to be exposed from the upper surface of the coil body; as well as a cutting step of cutting the coil body portion along a cutting plane parallel to the first direction and intersecting the columnar electrode and the first via electrode; In the process of forming the first conductive hole electrode, the first conductive hole electrode is formed in such a manner that, with respect to the exposed width on the cutting surface along a second direction orthogonal to the first direction when viewed from a direction orthogonal to the cutting surface of the coil body portion, the exposed width of the first conductive hole electrode is smaller than the exposed width of the columnar electrode.

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