Solid electrolytic capacitor and method for manufacturing solid electrolytic capacitor

Abstract

This solid electrolytic capacitor (10) is provided with: a capacitor element (20) which has an anode body (21) having a side surface (21a), an anode wire (22) that is partially embedded in the anode body (21) and has the remainder protruded from the side surface (21a), a dielectric layer (23) that is formed on the surface of the anode body (21), a solid electrolyte layer (24) that covers at least a part of the dielectric layer (23), and a cathode layer (25) that covers at least a part of the solid electrolyte layer (24) and has a first lower surface (25a); a metal member (30) which is connected to the anode wire (22) and has a second lower surface (30a); an outer covering resin (41) that covers the capacitor element (20) and at least a part of the metal member (30); an anode terminal (50) that is exposed from the outer covering resin (41) and has a first metal layer (51), which is connected to the second lower surface (30a), and a second metal layer (52); and a cathode terminal (60) that is exposed from the outer covering resin (41) and has a third metal layer (61), which is connected to the first lower surface (25a), and a fourth metal layer (62).

Description

Solid electrolytic capacitor and method for manufacturing the same CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This disclosure claims the benefit of priority to Japanese Patent Application No. 2024-100798, filed June 21, 2024, in the Japan Patent Office, the entire contents of which are incorporated herein by reference. In addition, all references cited in this disclosure are specifically incorporated by reference in their entirety.

[0002] The present disclosure relates to a solid electrolytic capacitor and a method for manufacturing a solid electrolytic capacitor.

[0003] Conventionally, a solid electrolytic capacitor including a porous anode body and an anode wire partially embedded in the anode body has been known (for example, Patent Document 1). Patent Document 1 discloses "a chip capacitor including a capacitor element including an anode lead wire, on which a dielectric oxide film, a solid electrolyte layer, and a cathode lead layer are sequentially formed, and then the capacitor element is covered with a resin exterior and a terminal electrode is formed on the exterior surface, wherein the anode lead wire and the anode terminal electrode are electrically connected, and the cathode lead layer located on approximately the same plane as the surface from which the anode lead wire is led out is connected to the cathode terminal electrode."

[0004] Japanese Patent Application Laid-Open No. 2002-25860

[0005] In recent years, as electronic devices incorporating solid electrolytic capacitors have become smaller and faster, there has been a demand for lower impedance solid electrolytic capacitors, more specifically, for reduced equivalent series resistance (ESR) and equivalent series inductance (ESL) of solid electrolytic capacitors. In this situation, one of the objectives of the present disclosure is to reduce the ESR and ESL of solid electrolytic capacitors.

[0006] One aspect of the present disclosure relates to a solid electrolytic capacitor, the solid electrolytic capacitor including at least one capacitor element including a porous anode body having a side surface, at least one anode wire partially embedded in the anode body and partially protruding from the side surface, a dielectric layer formed on a surface of the anode body, a solid electrolyte layer covering at least a portion of the dielectric layer, and a cathode layer covering at least a portion of the solid electrolyte layer and having a first lower surface, at least one metal member connected to the anode wire and having a second lower surface, an exterior resin covering at least a portion of the capacitor element and the metal member, at least one anode terminal including a first metal layer connected to the second lower surface and a second metal layer connected to the first metal layer and exposed from the exterior resin, and at least one cathode terminal including a third metal layer connected to the first lower surface and a fourth metal layer connected to the third metal layer and exposed from the exterior resin.

[0007] Another aspect of the present disclosure relates to a method for manufacturing a solid electrolytic capacitor. a fifth step of forming an exterior resin on the adhesive carrier so as to cover at least a portion of the capacitor element and the metal member; a sixth step of peeling off the adhesive carrier to expose from the exterior resin the second lower surface of the metal member and the first lower surface of the cathode layer of the capacitor element; a seventh step of forming a dry-plated layer including portions corresponding to the first metal layer and the third metal layer using a dry plating method; an eighth step of forming a wet-plated layer including portions corresponding to the second metal layer and the fourth metal layer using a wet plating method; and a ninth step of patterning the dry-plated layer and the wet-plated layer to form the first metal layer, the second metal layer, the third metal layer, and the fourth metal layer.

[0008] According to the present disclosure, the ESR and ESL of a solid electrolytic capacitor can be reduced.

[0009] 1A and 1B are diagrams schematically illustrating a solid electrolytic capacitor according to a first embodiment, where (a) is a front cross-sectional view and (b) is a side cross-sectional view taken along line II.

[0023] Figures are diagrams for explaining a method for manufacturing the solid electrolytic capacitor according to the first embodiment, where (a) shows a first step, (b) shows a second step, (c) shows a third and fourth step, and (d) shows a fifth step.

[0024] Figures are diagrams for explaining a method for manufacturing the solid electrolytic capacitor according to the first embodiment, where (a) shows a sixth step, (b) shows a seventh step, and (c) shows an eighth step.

[0025] Figures are diagrams for explaining a method for manufacturing the solid electrolytic capacitor according to the first embodiment, where (a) shows a ninth step, (b) shows a tenth step, and (c) shows a twelfth step.

[0026] Figures are diagrams for explaining a method for manufacturing the solid electrolytic capacitor according to a first modification of the first embodiment, where (a) shows a side cross-sectional view and (b) shows a solid electrolytic capacitor according to a second modification of the first embodiment.

[0027] Figures are diagrams for explaining a solid electrolytic capacitor according to a third modification of the first embodiment, where (a) shows a first step, (b) shows a second step, and (c) shows a third step.

[0028] Figures are diagrams for explaining a method for manufacturing the solid electrolytic capacitor according to the second embodiment, where (a) shows a second step, (b) shows a third step, and (c) shows a twelfth step.

[0029] Figures are diagrams for explaining a method for manufacturing the solid electrolytic capacitor according to the first embodiment, where (a) shows a third step, (b) shows a fourth step, and (c) shows a fifth step. 1 is a front cross-sectional view schematically showing a solid electrolytic capacitor according to Embodiment 3. FIG. 2 is a front cross-sectional view schematically showing a solid electrolytic capacitor according to a modification of Embodiment 3. FIG. 3 is a view schematically showing a solid electrolytic capacitor according to Embodiment 4, where (a) is a front cross-sectional view and (b) is a plan cross-sectional view taken along line XI-XI. FIG. 4 is a view schematically showing a solid electrolytic capacitor according to Embodiment 5, where (a) is a front cross-sectional view and (b) is a plan cross-sectional view taken along line XII-XII. FIG. 5 is a view schematically showing a solid electrolytic capacitor according to a modification of Embodiment 5, where (a) is a front cross-sectional view and (b) is a plan cross-sectional view taken along line XIII-XIII. FIG. 6 is a front cross-sectional view schematically showing a solid electrolytic capacitor according to Embodiment 6. FIG. 7 is a view for explaining a method for manufacturing the solid electrolytic capacitor according to Embodiment 6, where (a) shows the sixth step, (b) shows the eleventh step, and (c) shows the seventh and eighth steps. 10A to 10C are diagrams for explaining a method for manufacturing a solid electrolytic capacitor according to a sixth embodiment, in which (a) shows a ninth step, (b) shows a tenth step, and (c) shows a twelfth step. 11A is a front cross-sectional view schematically showing a solid electrolytic capacitor according to a first modification of the sixth embodiment. 12C is a front cross-sectional view schematically showing a solid electrolytic capacitor according to a second modification of the sixth embodiment. 13C is a front cross-sectional view schematically showing a solid electrolytic capacitor according to a third modification of the sixth embodiment.

[0010] The novel features of the present invention are set forth in the appended claims, but the present invention, both in terms of structure and content, together with other objects and features of the present invention, will be better understood from the following detailed description taken in conjunction with the drawings.

[0011] The following describes examples of embodiments of a solid electrolytic capacitor and a method for manufacturing a solid electrolytic capacitor according to the present disclosure. However, the present disclosure is not limited to the examples described below. While specific numerical values ​​and materials are used in the following description, other numerical values ​​and materials may be used as long as the effects of the present disclosure are obtained. Note that the following description will be given assuming that the mounting surface of the solid electrolytic capacitor is the lower side.

[0012] (Solid Electrolytic Capacitor) A solid electrolytic capacitor according to the present disclosure includes at least one capacitor element, at least one metal member, an exterior resin, at least one anode terminal, and at least one cathode terminal, the at least one anode terminal and the at least one cathode terminal being electrically insulated from each other.

[0013] At least one capacitor element includes an anode body, at least one anode wire, a dielectric layer, a solid electrolyte layer, and a cathode layer.

[0014] The anode body is a porous anode body having side surfaces. The anode body is, for example, a porous sintered body having a roughly rectangular parallelepiped shape obtained by sintering metal particles. The roughly rectangular parallelepiped shape of the anode body means a shape having three pairs (i.e., six) of opposing main surfaces (i.e., six main surfaces including the side surfaces). One of the six main surfaces is a side surface, and the other is a bottom surface. The first and second bottom surfaces described below face in the same direction as the bottom surface. Adjacent main surfaces may intersect with each other at an angle of 80° or more and 100° or less. The metal particles may be particles of valve metals such as tantalum, titanium, or niobium. One type of metal particle may be used alone, or two or more types may be used in combination. The metal particles may also be an alloy of two or more metals. For example, an alloy containing a valve metal and silicon, vanadium, boron, or the like may be used. A compound containing a valve metal and a typical element such as nitrogen may also be used. The valve metal alloy contains a valve metal as a main component, for example, 50 atomic % or more of the valve metal.

[0015] At least one anode wire is partially embedded in the anode body and the remainder protrudes from the side surface of the anode body. The shape of the anode wire is not particularly limited and may be, for example, columnar or plate-shaped. The material of the anode wire is also not particularly limited and, in addition to the valve metals mentioned above, examples include copper, aluminum, and aluminum alloys. The anode body and the anode wire may be made of the same material or different materials. The anode wire has an embedded portion embedded in the anode body and a protruding portion protruding from the anode body.

[0016] The dielectric layer is a layer formed on the surface of the anode body. The dielectric layer is made of, for example, a metal oxide. Examples of methods for forming a layer containing a metal oxide on the surface of the anode body include a method of anodizing the surface of the anode body by immersing the anode body in a chemical conversion solution, a gas phase method such as an ALD method (Atomic Layer Deposition method), and a method of heating the anode body in an oxygen-containing atmosphere. The dielectric layer is not limited to a layer containing a metal oxide, and may be any layer having insulating properties.

[0017] The solid electrolyte layer is a layer that covers at least a portion of the dielectric layer. For example, a manganese compound or a conductive polymer is used. Examples of conductive polymers include polypyrrole, polythiophene, polyfuran, polyaniline, polyacetylene, polyphenylene, polyparaphenylene vinylene, polyacene, polythiophene vinylene, polyfluorene, polyvinyl carbazole, polyvinyl phenol, polypyridine, or derivatives of these polymers. These may be used alone or in combination. The conductive polymer may also be a copolymer of two or more monomers. Among these, polythiophene, polyaniline, polypyrrole, etc. are preferred because of their excellent conductivity. Among these, polypyrrole is preferred because of its excellent water repellency.

[0018] The solid electrolyte layer containing the conductive polymer is formed, for example, by polymerizing a raw material monomer on a dielectric layer or by applying a liquid containing the conductive polymer to the dielectric layer. The solid electrolyte layer is composed of one or more solid electrolyte layers. When the solid electrolyte layer is composed of two or more solid electrolyte layers, the composition and formation method (polymerization method) of the conductive polymer used in each layer may be different.

[0019] In this specification, polypyrrole, polythiophene, polyfuran, polyaniline, etc. refer to polymers having polypyrrole, polythiophene, polyfuran, polyaniline, etc. as their basic skeletons, respectively. Therefore, polypyrrole, polythiophene, polyfuran, polyaniline, etc. may also include their respective derivatives. For example, polythiophene includes poly(3,4-ethylenedioxythiophene).

[0020] Various dopants may be added to the polymerization liquid for forming the conductive polymer, or the solution or dispersion of the conductive polymer in order to improve the conductivity of the conductive polymer. The dopant is not particularly limited, but examples thereof include 1,5-naphthalenedisulfonic acid, 1,6-naphthalenedisulfonic acid, 1-octane sulfonic acid, 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 2,6-naphthalenedisulfonic acid, 2,7-naphthalenedisulfonic acid, 2-methyl-5-isopropylbenzenesulfonic acid, 4-octylbenzenesulfonic acid, 4-nitrotoluene-2-sulfonic acid, m-nitrobenzenesulfonic acid, n-octyl sulfonic acid, n-butanesulfonic acid, n-hexanesulfonic acid, o-nitrobenzenesulfonic acid, p-ethylbenzenesulfonic acid, trifluoromethanesulfonic acid, hydroxybenzenesulfonic acid, butylnaphthalenesulfonic acid, benzenesulfonic acid, polystyrenesulfonic acid, polyvinylsulfonic acid, methanesulfonic acid, and derivatives thereof. Examples of the derivatives include metal salts such as lithium salts, potassium salts, and sodium salts; ammonium salts such as methylammonium salts, dimethylammonium salts, and trimethylammonium salts; piperidium salts, pyrrolidium salts, and pyrrolinium salts.

[0021] The cathode layer is a layer covering at least a portion of the solid electrolyte layer and has a first lower surface. This first lower surface is also the lower surface of the capacitor element. The cathode layer may have a carbon layer formed on the solid electrolyte layer and a metal paste layer (e.g., a silver paste layer) formed on the carbon layer. The carbon layer is formed so as to cover at least a portion of the solid electrolyte layer. The carbon layer is made of a composition including a conductive carbon material such as graphite. The metal paste layer is made of a composition including, for example, silver particles and a resin. The configuration of the cathode layer is not limited to this, and may be any configuration that has a current collecting function.

[0022] The thickness of the cathode layer may be, for example, 1 μm or more and 100 μm or less. When the cathode layer includes a carbon layer and a metal paste layer, the thickness of the carbon layer may be, for example, 0.1 μm or more and 50 μm or less, and the thickness of the metal paste layer may be, for example, 1 μm or more and 50 μm or less. By providing such a very thin cathode layer, the ESR of the solid electrolytic capacitor can be effectively reduced.

[0023] At least one metal member is connected to the anode wire (more specifically, to the protruding portion of the anode wire). The metal member has a second lower surface. The second lower surface may be substantially parallel to the first lower surface. Here, "substantially parallel" means that the angle between the two surfaces is 5° or less. The material of the metal member is not particularly limited, and may be, for example, copper or a copper alloy, and the surface may be plated as needed. The metal member may be a metal plate-like member or a columnar member (e.g., a rectangular timber). The width dimension of the metal member (i.e., the length dimension perpendicular to the paper surface in FIG. 1 ) may be, for example, 40% or more and 95% or less of the width dimension of the exterior resin. Increasing the width dimension of the metal member in this manner reduces the electrical resistance of the metal member and the ESR of the solid electrolytic capacitor.

[0024] The exterior resin covers at least a portion of the capacitor element and the metal member. For example, at least a portion of the lower surface of the capacitor element (or the first lower surface of the cathode layer) and at least a portion of the second lower surface of the metal member may not be covered with the exterior resin. Examples of the exterior resin include epoxy resin, phenolic resin, silicone resin, melamine resin, urea resin, alkyd resin, polyurethane, polyimide, and unsaturated polyester. The exterior resin may contain a substance other than resin (such as an inorganic filler).

[0025] At least one anode terminal has a first metal layer and a second metal layer and is exposed from the exterior resin. The first metal layer is connected to the second lower surface of the metal member. The second metal layer is connected to the first metal layer. That is, the second metal layer is electrically connected to the anode wire of the capacitor element via the first metal layer or via the first metal layer and the metal member.

[0026] At least one cathode terminal has a third metal layer and a fourth metal layer and is exposed from the exterior resin. The third metal layer is connected to the first lower surface of the cathode layer (or the lower surface of the capacitor element). The fourth metal layer is connected to the third metal layer. That is, the fourth metal layer is electrically connected to the cathode layer of the capacitor element via the third metal layer.

[0027] In the solid electrolytic capacitor having the above-described configuration, the anode terminal and the cathode terminal each have multiple metal layers and are electrically connected to the capacitor element without using a lead frame, thereby reducing the ESR and ESL of the solid electrolytic capacitor.

[0028] The solid electrolytic capacitor may further include a sealing resin that covers at least a portion of the cathode layer and the exterior resin between the anode terminal and the cathode terminal. The type of the sealing resin is not particularly limited and may be, for example, a fluorine-containing resin. The sealing resin may cover at least a portion of the first lower surface of the cathode layer (e.g., a portion of the first lower surface to which the cathode terminal is not connected) and at least a portion of the lower surface of the exterior resin.

[0029] The first metal layer and the third metal layer may each be a dry-plated layer. The second metal layer and the fourth metal layer may each be a wet-plated layer. The dry-plated layer is formed by a dry plating method, and the wet-plated layer is formed by a wet plating method. Dry plating methods include vacuum plating (PVD method) and chemical vapor deposition (CVD method). Vacuum plating (PVD method) includes sputtering, vacuum deposition, ion plating, etc. Wet plating methods include electroplating (e.g., electrolytic plating), electroless plating, chemical plating, and hot-dip plating. For example, sputtering may be used as the dry plating method, and electroplating may be used as the wet plating method.

[0030] The dry-plated layer may contain at least one metal material selected from the group consisting of Ti (titanium), Cr (chromium), and Ni (nickel). The wet-plated layer may contain at least one metal material selected from the group consisting of Cu (copper), Ni (nickel), Sn (tin), and Al (aluminum). For example, the dry-plated layer may contain Ti and the wet-plated layer may contain Cu. The dry-plated layer may be formed as a single layer or as multiple layers. For example, a thin Ti layer and a thin Cu layer may be formed by sputtering as the dry-plated layer. More specifically, the thin Ti layer may be formed first, followed by the formation of the thin Cu layer. In this case, a relatively thick wet-plated Cu layer may be formed by electrolytic plating on the sputtered layer of this two-layer structure.

[0031] The thickness of the dry-plated layer may be 100 nm or more and 3000 nm or less. The thickness of the wet-plated layer may be 3 μm or more and 500 μm or less. In this way, the dry-plated layer is very thin, whereas the wet-plated layer can be thick, resulting in the anode terminal and the cathode terminal being thick overall.

[0032] The capacitor element may have a convex portion formed at a connection portion between the cathode layer and the cathode terminal. The convex portion may protrude downward. Here, the lower surface of the convex portion constitutes at least a part of the first lower surface. If such a convex portion is present, when forming the exterior resin, the resin material flows into the area surrounding the convex portion, thereby achieving electrical insulation between the anode terminal and the cathode terminal without providing the sealing resin. Note that the sealing resin may be provided when the capacitor element has a convex portion.

[0033] The protrusion length of the protrusions may be 100 μm or more and 2000 μm or less. By setting the protrusion length of the protrusions (i.e., the vertical length from the base end to the tip of the protrusions) within this range, it is possible to easily form an exterior resin around the peripheral region of the protrusions while suppressing an increase in size of the solid electrolytic capacitor.

[0034] The at least one anode wire may include a plurality of anode wires, in which case the ESR of the solid electrolytic capacitor can be further reduced by increasing the thickness of the conductive path on the anode side.

[0035] The anode wire may be formed in a plate shape, in which case the conductive path on the anode side can be made thicker, thereby further reducing the ESR of the solid electrolytic capacitor.

[0036] The at least one capacitor element may include a plurality of capacitor elements, each having an anode wire connected to the same metal member, and the total surface area of ​​the capacitor elements may be increased, thereby improving the capacitance of the solid electrolytic capacitor.

[0037] The anode wire may penetrate the anode body. The at least one metal member may include a first metal member connected to one protrusion of the anode wire and a second metal member connected to the other protrusion of the anode wire. The at least one anode terminal may include a first anode terminal connected to the second lower surface of the first metal member and a second anode terminal connected to the second lower surface of the second metal member. In this case, a three-terminal solid electrolytic capacitor having two anode terminals can be easily formed.

[0038] The at least one capacitor element may include a first capacitor element and a second capacitor element having anode wires that face in opposite directions and protrude outward. The at least one metal member may include a first metal member connected to the anode wire of the first capacitor element and a second metal member connected to the anode wire of the second capacitor element. The at least one anode terminal may include a first anode terminal connected to the second lower surface of the first metal member and a second anode terminal connected to the second lower surface of the second metal member. In this case, a three-terminal solid electrolytic capacitor having two anode terminals can be easily formed using first and second capacitor elements having a structure similar to that of a conventional capacitor.

[0039] The at least one capacitor element may include a first capacitor element and a second capacitor element having anode wires that face inward and point in opposite directions. The at least one cathode terminal may include a first cathode terminal connected to the cathode layer of the first capacitor element and a second cathode terminal connected to the cathode layer of the second capacitor element. In this case, a three-terminal solid electrolytic capacitor having two cathode terminals can be easily formed using first and second capacitor elements having a structure similar to that of a conventional capacitor.

[0040] The first and second metal layers may extend across one side of the exterior resin. The third and fourth metal layers may extend across another side of the exterior resin. With this configuration, when the solid electrolytic capacitor is solder-mounted on a substrate, a solder fillet is likely to be formed on the side, improving the bonding strength between the two. Furthermore, the mounting state can be easily checked, reducing mounting defects and connection failures.

[0041] The first metal layer corresponding to one side of the exterior resin may be connected to at least one of the anode wire and the metal member. This configuration increases the conductive path between the anode terminal and the capacitor element, thereby further reducing the ESR of the solid electrolytic capacitor. The first metal layer corresponding to one side of the exterior resin may be connected only to the anode wire, only to the metal member, or to both.

[0042] The third metal layer corresponding to the other side of the exterior resin may be connected to a side of the cathode layer. With this configuration, the conductive path between the cathode terminal and the capacitor element is increased, thereby further reducing the ESR of the solid electrolytic capacitor.

[0043] (Method for manufacturing a solid electrolytic capacitor) The method for manufacturing a solid electrolytic capacitor according to the present disclosure is a method for manufacturing the above-described solid electrolytic capacitor, and includes steps 1, 2, 3, 4, 5, 6, 7, 8, and 9.

[0044] In the first step, an adhesive carrier having adhesive properties is prepared. For example, the adhesive carrier may be a carrier sheet having a two-layer structure including a support substrate and an adhesive layer provided thereon. The support substrate may be flexible.

[0045] In the second step, the metal member is placed on the adhesive carrier, and at this time, the second lower surface of the metal member may be brought into contact with the adhesive carrier.

[0046] In the third step, the capacitor element is placed on the adhesive carrier, and at this time, the first lower surface of the cathode layer of the capacitor element may be in contact with the adhesive carrier, and the anode wire may be in contact with the upper surface of the metal member.

[0047] In the fourth step, the anode wire is connected to the metal member. The method of connection is not particularly limited, but it is conceivable to connect the anode wire to the metal member by welding, for example.

[0048] In a fifth step, an exterior resin is formed on the adhesive carrier so as to cover at least a portion of the capacitor element and the metal member, while a first lower surface of the capacitor element and a second lower surface of the metal member, which are in contact with the adhesive carrier, are not covered by the exterior resin.

[0049] In the sixth step, the adhesive carrier is peeled off to expose the second lower surface of the metal member and the first lower surface of the cathode layer of the capacitor element from the exterior resin.

[0050] In the seventh step, a dry-plated layer including portions corresponding to the first metal layer and the third metal layer is formed using a dry plating method. The dry-plated layer may be a single layer or may include multiple layers.

[0051] In the eighth step, a wet-plated layer including portions corresponding to the second metal layer and the fourth metal layer is formed by wet plating. The wet-plated layer may be formed on the lower surface of the dry-plated layer.

[0052] In the ninth step, the dry-plated layer and the wet-plated layer are patterned to form a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer. The patterning method is not particularly limited. For example, the desired patterning may be achieved by using photolithography, which involves resist formation, exposure and development, and etching.

[0053] The method for manufacturing a solid electrolytic capacitor may further include a tenth step of forming a sealing resin that covers at least a portion of the cathode layer and the exterior resin (particularly, a portion of the surface that was covered with the adhesive carrier). The tenth step may be performed at any stage after the sixth step.

[0054] Step 10 may be performed between Steps 6 and 7. That is, after the first and second lower surfaces are exposed from the exterior resin, the sealing resin may be formed before the dry-plated layer is formed. In this configuration, when an etching solution is used to pattern the dry-plated layer and the wet-plated layer, the etching solution can be prevented from coming into contact with the capacitor element.

[0055] The method for manufacturing a solid electrolytic capacitor may further include an eleventh step between the sixth and seventh steps, in which portions of the exterior resin on both sides of the capacitor element are removed. By performing the eleventh step, it is possible to form a dry plating layer on the portions corresponding to both sides of the capacitor element. A technique called half dicing can be used for this removal.

[0056] As described above, according to the present disclosure, the ESR and ESL of the solid electrolytic capacitor can be reduced by connecting the anode terminal and cathode terminal, each having a multi-layer structure, to the capacitor element via a short conductive path.

[0057] An example of a solid electrolytic capacitor and a method for manufacturing a solid electrolytic capacitor according to the present disclosure will be described in detail below with reference to the drawings. The components and steps described above can be applied to the components and steps of the example solid electrolytic capacitor and method for manufacturing a solid electrolytic capacitor described below. The components and steps of the example solid electrolytic capacitor and method for manufacturing a solid electrolytic capacitor described below can be modified based on the above description. Furthermore, the matters described below may be applied to the above-described embodiment. Among the components and steps of the example solid electrolytic capacitor and method for manufacturing a solid electrolytic capacitor described below, components and steps that are not essential to the solid electrolytic capacitor and method for manufacturing a solid electrolytic capacitor according to the present disclosure may be omitted. Note that the diagrams shown below are schematic and do not accurately reflect the shapes and numbers of actual components.

[0058] First Embodiment A first embodiment of the present disclosure will be described below. First, the configuration of a solid electrolytic capacitor 10 of this embodiment will be described, and then a method for manufacturing the solid electrolytic capacitor of this embodiment will be described.

[0059] 1, a solid electrolytic capacitor 10 of this embodiment is a two-terminal solid electrolytic capacitor including a capacitor element 20, a metal member 30, an exterior resin 41, a sealing resin 42, an anode terminal 50, and a cathode terminal 60. The anode terminal 50 and the cathode terminal 60 are electrically insulated from each other.

[0060] The capacitor element 20 includes an anode body 21 , an anode wire 22 , a dielectric layer 23 , a solid electrolyte layer 24 , and a cathode layer 25 .

[0061] The anode body 21 is a porous anode body having a side surface 21 a. The anode body 21 is a porous sintered body having a roughly rectangular parallelepiped shape obtained by sintering particles of a valve metal (tantalum in this example), but is not limited to this.

[0062] Anode wire 22 is partially embedded in anode body 21 and the remainder protrudes from side surface 21 a of anode body 21. Anode wire 22 is formed in a generally cylindrical shape. Anode wire 22 is made of tantalum, but is not limited to this. Anode wire 22 has embedded portion 22 a embedded in anode body 21 and protruding portion 22 b protruding from anode body 21.

[0063] The dielectric layer 23 is a layer formed on the surface of the anode body 21. The dielectric layer 23 is made of a metal oxide (tantalum pentoxide in this example), but is not limited to this.

[0064] The solid electrolyte layer 24 is a layer that covers at least a part of the dielectric layer 23. The solid electrolyte layer 24 includes a conductive polymer (polypyrrole in this example), but is not limited to this.

[0065] Cathode layer 25 is a layer that covers at least a portion of solid electrolyte layer 24 and has first lower surface 25a. Cathode layer 25 includes carbon layer 25b formed on solid electrolyte layer 24 and metal paste layer 25c formed on carbon layer 25b, but is not limited to this.

[0066] The metal member 30 is connected to the protruding portion 22b of the anode wire 22. The metal member 30 is formed in a generally rectangular parallelepiped shape and has a second lower surface 30a. The second lower surface 30a is located on the same plane as the first lower surface 25a. The metal member 30 is made of copper, but is not limited to this.

[0067] The exterior resin 41 covers at least a portion of the capacitor element 20 and the metal member 30. In this embodiment, the exterior resin 41 covers the capacitor element 20 and the metal member 30 except for the first lower surface 25a and the second lower surface 30a. The exterior resin 41 is made of an insulating resin (epoxy resin in this example).

[0068] The sealing resin 42 covers at least a portion of the cathode layer 25 and the exterior resin 41, at least between the anode terminal 50 and the cathode terminal 60. The sealing resin 42 in this embodiment covers the first lower surface 25a of the cathode layer 25 and the lower surface of the exterior resin 41, excluding the portions where the anode terminal 50 and the cathode terminal 60 are formed. The sealing resin 42 is made of an insulating and water-repellent resin.

[0069] The anode terminal 50 has a first metal layer 51 and a second metal layer 52, and is exposed from the exterior resin 41. The first metal layer 51 is connected to the second lower surface 30a of the metal member 30. The first metal layer 51 is a dry-plated layer containing Ti, and has a thickness of 100 nm or more and 3000 nm or less. The second metal layer 52 is connected to the first metal layer 51. The second metal layer 52 is a wet-plated layer containing Cu, and has a thickness of 3 μm or more and 500 μm or less.

[0070] Cathode terminal 60 has a third metal layer 61 and a fourth metal layer 62, and is exposed from exterior resin 41. Third metal layer 61 is connected to first lower surface 25a of cathode layer 25. Third metal layer 61 is a dry-plated layer containing Ti, and has a thickness of 100 nm or more and 3000 nm or less. Fourth metal layer 62 is connected to third metal layer 61. Fourth metal layer 62 is a wet-plated layer containing Cu, and has a thickness of 3 μm or more and 500 μm or less.

[0071] (Method for Manufacturing Solid Electrolytic Capacitor) Next, a method for manufacturing the above-described solid electrolytic capacitor 10 will be described with reference to Figures 2 to 4. The method for manufacturing the solid electrolytic capacitor of this embodiment includes a first step, a second step, a third step, a fourth step, a fifth step, a sixth step, a seventh step, an eighth step, a ninth step, a tenth step, and a twelfth step.

[0072] In the first step, an adhesive carrier 100 having adhesiveness is prepared (FIG. 2(a)). The adhesive carrier 100 of this embodiment is composed of a carrier sheet having a two-layer structure including a flexible supporting substrate 101 and an adhesive layer 102 provided thereon.

[0073] In the second step, the metal member 30 is placed on the adhesive carrier 100 (FIG. 2B). At this time, the second lower surface 30a of the metal member 30 is brought into contact with the adhesive layer 102 of the adhesive carrier 100.

[0074] In the third step, the capacitor element 20 is placed on the adhesive carrier 100 (FIG. 2(c)). At this time, the first lower surface 25a of the cathode layer 25 of the capacitor element 20 is brought into contact with the adhesive layer 102 of the adhesive carrier 100, and the protruding portion 22b of the anode wire 22 is brought into contact with the upper surface of the metal member 30.

[0075] In the fourth step, the anode wire 22 is connected to the metal member 30. In the fourth step of this embodiment, the anode wire 22 is connected to the metal member 30 by welding.

[0076] In the fifth step, an exterior resin 41 is formed on the adhesive carrier 100 so as to cover at least a portion of the capacitor element 20 and the metal member 30 (FIG. 2(d)). At this time, the first lower surface 25a of the capacitor element 20 and the second lower surface 30a of the metal member 30, which are in contact with the adhesive carrier 100, are not covered by the exterior resin 41.

[0077] In the sixth step, the adhesive carrier 100 is peeled off to expose the second lower surface 30a of the metal member 30 and the first lower surface 25a of the cathode layer 25 of the capacitor element 20 from the exterior resin 41 (FIG. 3(a)).

[0078] In the seventh step, a dry plating layer 70 including portions corresponding to the first metal layer 51 and the third metal layer 61 is formed using a dry plating method (sputtering in this example) (FIG. 3(b)).

[0079] In the eighth step, a wet plating method (in this example, electroplating) is used to form a wet plating layer 80 on the underside of the dry plating layer 70, including portions corresponding to the second metal layer 52 and the fourth metal layer 62 (Figure 3(c)).

[0080] In the ninth step, the dry-plated layer 70 and the wet-plated layer 80 are patterned to form a first metal layer 51, a second metal layer 52, a third metal layer 61, and a fourth metal layer 62 ( FIG. 4( a) ). In the ninth step of this embodiment, the patterning is performed using photolithography.

[0081] In the tenth step, a sealing resin 42 is formed to cover at least a part of the cathode layer 25 and the exterior resin 41 (FIG. 4B). In this embodiment, the tenth step is performed after the ninth step, but instead, the tenth step may be performed between the sixth step and the seventh step.

[0082] In a twelfth step, a portion of the exterior resin 41 and the sealing resin 42 is removed to obtain the solid electrolytic capacitor 10 of this embodiment (FIG. 4(c)). The removal method is not particularly limited, and for example, a dicing method such as a blade dicing method or a laser ablation method can be used.

[0083] Variation 1 of Embodiment 1 Variation 1 of Embodiment 1 of the present disclosure will be described. Solid electrolytic capacitor 10 of this variation differs from embodiment 1 above in the configuration of capacitor element 20. Specifically, as shown in FIG. 5 , capacitor element 20 of this variation has a convex portion 26 formed at the connection portion between cathode layer 25 and cathode terminal 60. Convex portion 26 protrudes downward, and the protrusion length is 100 μm or more and 2000 μm or less. Solid electrolytic capacitor 10 of this variation does not include sealing resin 42, but is not limited to this.

[0084] Second Modification of First Embodiment A second modification of the first embodiment of the present disclosure will now be described. The solid electrolytic capacitor 10 of this modification differs from the first embodiment in that it includes a plurality of anode wires 22. Specifically, as shown in FIG. 6 , the capacitor element 20 of this modification includes two anode wires 22. Each anode wire 22 is connected to a metal member 30.

[0085] Third Modification of First Embodiment A third modification of the first embodiment of the present disclosure will now be described. The solid electrolytic capacitor 10 of this modification differs from the first embodiment in the shape of the anode wire 22. Specifically, as shown in Fig. 7 , the anode wire 22 of this modification is formed in a plate shape extending in the width direction of the solid electrolytic capacitor 10 (the left-right direction in Fig. 7 ). The lower surface of the anode wire 22 and the upper surface of the metal member 30 are in surface contact.

[0086] Second Embodiment A second embodiment of the present disclosure will be described. The solid electrolytic capacitor 10 of this embodiment differs from the first embodiment in the number of capacitor elements 20. Specifically, as shown in FIG. 8 , the solid electrolytic capacitor 10 of this embodiment includes two capacitor elements 20 arranged in parallel. The side surfaces 21 a of the anode bodies 21 of the two capacitor elements 20 (i.e., the side surfaces 21 a from which the anode wires 22 protrude) face in the same direction. The anode wires 22 of each capacitor element 20 are connected to the same metal member 30.

[0087] Embodiment 3 A third embodiment of the present disclosure will be described. The solid electrolytic capacitor 10 of this embodiment differs from the first embodiment in that it is a three-terminal type having two anode terminals 50. Specifically, as shown in FIG. 9 , the solid electrolytic capacitor 10 of this embodiment has an anode wire 22 that penetrates the anode body 21 in the capacitor element 20. Therefore, the anode wire 22 of this embodiment has two protrusions 22b. The solid electrolytic capacitor 10 includes a first metal member 30A connected to one of the protrusions 22b and a second metal member 30B connected to the other protrusion 22b. The solid electrolytic capacitor 10 also includes a first anode terminal 50A connected to the second lower surface 30a of the first metal member 30A and a second anode terminal 50B connected to the second lower surface 30a of the second metal member 30B.

[0088] Modification of Embodiment 3 A modification of Embodiment 3 of the present disclosure will be described. The solid electrolytic capacitor 10 of this modification differs from the third embodiment in the configuration of the capacitor element 20. Specifically, as shown in FIG. 10 , the capacitor element 20 of this modification has a protrusion 26 formed at the connection portion between the cathode layer 25 and the cathode terminal 60. The protrusion 26 protrudes downward, and the protrusion length is 100 μm or more and 2000 μm or less. The solid electrolytic capacitor 10 of this modification does not include the sealing resin 42, but is not limited to this.

[0089] Embodiment 4 A fourth embodiment of the present disclosure will be described. The solid electrolytic capacitor 10 of this embodiment differs from the first embodiment in that it is a three-terminal type having two anode terminals 50. Specifically, as shown in FIG. 11 , the solid electrolytic capacitor 10 of this embodiment includes a first capacitor element 20A and a second capacitor element 20B. The anode wire 22 of the first capacitor element 20A and the anode wire 22 of the second capacitor element 20B face in opposite directions and protrude outward. The solid electrolytic capacitor 10 includes a first metal member 30A connected to the anode wire 22 of the first capacitor element 20A and a second metal member 30B connected to the anode wire 22 of the second capacitor element 20B. The solid electrolytic capacitor 10 also includes a first anode terminal 50A connected to the second lower surface 30a of the first metal member 30A and a second anode terminal 50B connected to the second lower surface 30a of the second metal member 30B.

[0090] Embodiment 5 A fifth embodiment of the present disclosure will be described. The solid electrolytic capacitor 10 of this embodiment differs from the first embodiment in that it is a three-terminal type having two cathode terminals 60. Specifically, as shown in FIG. 12 , the solid electrolytic capacitor 10 of this embodiment includes a first capacitor element 20A and a second capacitor element 20B. The anode wire 22 of the first capacitor element 20A and the anode wire 22 of the second capacitor element 20B face inward and point in opposite directions. The solid electrolytic capacitor 10 also includes a first cathode terminal 60A connected to the cathode layer 25 of the first capacitor element 20A and a second cathode terminal 60B connected to the cathode layer 25 of the second capacitor element 20B.

[0091] Modification of Embodiment 5 A modification of Embodiment 5 of the present disclosure will be described. The solid electrolytic capacitor 10 of this modification differs from the above-described Embodiment 5 in the configuration of the capacitor element 20. Specifically, as shown in FIG. 13 , the capacitor element 20 of this modification has a convex portion 26 formed at the connection portion between the cathode layer 25 and the cathode terminal 60. The convex portion 26 protrudes downward, and the protrusion length is 100 μm or more and 2000 μm or less. The solid electrolytic capacitor 10 of this modification does not include the sealing resin 42, but is not limited to this.

[0092] Sixth Embodiment A sixth embodiment of the present disclosure will be described. A solid electrolytic capacitor 10 of this embodiment differs from the first embodiment in the configuration of an anode terminal 50 and a cathode terminal 60. Specifically, in the solid electrolytic capacitor 10 of this embodiment, as shown in FIG. 14 , a first metal layer 51 and a second metal layer 52 extend across one side surface of the exterior resin 41 (the left side surface in FIG. 14 ), and a third metal layer 61 and a fourth metal layer 62 extend across another side surface of the exterior resin 41 (the right side surface in FIG. 14 ).

[0093] As shown in FIGS. 15 and 16 , the method for manufacturing a solid electrolytic capacitor of this embodiment includes steps 6, 11, 7, 8, 9, 10, and 12 in addition to steps 1 to 5, which are not shown.

[0094] In the sixth step, the adhesive carrier 100 (see Figure 2) is peeled off to expose the second lower surface 30a of the metal member 30 and the first lower surface 25a of the cathode layer 25 of the capacitor element 20 from the exterior resin 41 (Figure 15(a)).

[0095] In an eleventh step, portions of exterior resin 41 on both sides (both left and right sides in the illustrated example) of capacitor element 20 are removed by half dicing (FIG. 15B).

[0096] In the seventh and eighth steps, a dry plating method (in this example, sputtering) is used to form a dry plating layer 70 including portions corresponding to the first metal layer 51 and the third metal layer 61, and then a wet plating method (in this example, electroplating) is used to form a wet plating layer 80 including portions corresponding to the second metal layer 52 and the fourth metal layer 62 on the surface of the dry plating layer 70 (Figure 15(c)).

[0097] In the ninth step, the dry-plated layer 70 and the wet-plated layer 80 are patterned to form a first metal layer 51, a second metal layer 52, a third metal layer 61, and a fourth metal layer 62 ( FIG. 16( a) ). In the ninth step of this embodiment, the patterning is performed using photolithography.

[0098] In the tenth step, a sealing resin 42 is formed to cover at least a part of the cathode layer 25 and the exterior resin 41 (FIG. 16(b)). Note that in this embodiment, the tenth step is performed after the ninth step, but instead, the tenth step may be performed between the sixth step and the seventh step.

[0099] In step 12, the exterior resin 41 and the metal layers 51, 52, 61, and 62 are partially removed to obtain the solid electrolytic capacitor 10 of this embodiment ( FIG. 16( c) ). The removal method is not particularly limited, and for example, a dicing method such as a blade dicing method or a laser ablation method can be used. In step 12 of this embodiment, a portion of the upper side of the exterior resin 41 is removed by polishing.

[0100] A first modification of the sixth embodiment of the present disclosure will now be described. The solid electrolytic capacitor 10 of this modification differs from the sixth embodiment in that the anode terminal 50 and the cathode terminal 60 are connected to the capacitor element 20 on each side of the exterior resin 41. Specifically, in the solid electrolytic capacitor 10 of this modification, as shown in FIG. 17 , the first metal layer 51 corresponding to one side of the exterior resin 41 is connected to the anode wire 22 and the metal member 30, and the third metal layer 61 corresponding to the other side of the exterior resin 41 is connected to the side of the cathode layer 25.

[0101] A second modification of the sixth embodiment of the present disclosure will now be described. The solid electrolytic capacitor 10 of this modification differs from the sixth embodiment in that the anode terminal 50 and the cathode terminal 60 are connected to the capacitor element 20 on each side of the exterior resin 41. Specifically, in the solid electrolytic capacitor 10 of this modification, as shown in FIG. 18 , the first metal layer 51 corresponding to one side of the exterior resin 41 is connected to the metal member 30, and the third metal layer 61 corresponding to the other side of the exterior resin 41 is connected to the side of the cathode layer 25.

[0102] A third modification of the sixth embodiment of the present disclosure will now be described. The solid electrolytic capacitor 10 of this modification differs from the sixth embodiment in that the anode terminal 50 and the cathode terminal 60 are connected to the capacitor element 20 on each side of the exterior resin 41. Specifically, in the solid electrolytic capacitor 10 of this modification, as shown in FIG. 19 , the first metal layer 51 corresponding to one side of the exterior resin 41 is connected to the anode wire 22, and the third metal layer 61 corresponding to the other side of the exterior resin 41 is connected to the side of the cathode layer 25.

[0103] <<Supplementary Note>> The above embodiments disclose the following technology: (Technology 1) A solid electrolytic capacitor comprising: at least one capacitor element including: a porous anode body having a side surface; at least one anode wire partially embedded in the anode body and partially protruding from the side surface; a dielectric layer formed on a surface of the anode body; a solid electrolyte layer covering at least a portion of the dielectric layer; and a cathode layer covering at least a portion of the solid electrolyte layer and having a first lower surface; at least one metal member connected to the anode wire and having a second lower surface; an exterior resin covering at least a portion of the capacitor element and the metal member; at least one anode terminal having a first metal layer connected to the second lower surface and a second metal layer connected to the first metal layer, and exposed from the exterior resin; and at least one cathode terminal having a third metal layer connected to the first lower surface and a fourth metal layer connected to the third metal layer, and exposed from the exterior resin. (Technology 2) The solid electrolytic capacitor according to Technology 1, further comprising a sealing resin covering at least a portion of the cathode layer and the exterior resin at least between the anode terminal and the cathode terminal. (Technology 3) The solid electrolytic capacitor according to Technology 1 or 2, wherein the first metal layer and the third metal layer are each dry-plated layers, and the second metal layer and the fourth metal layer are each wet-plated layers. (Technology 4) The solid electrolytic capacitor according to Technology 3, wherein the dry-plated layer contains at least one metal material selected from the group consisting of Ti, Cr, and Ni, and the wet-plated layer contains at least one metal material selected from the group consisting of Cu, Ni, Sn, and Al. (Technology 5) The solid electrolytic capacitor according to Technology 3 or 4, wherein the dry-plated layer has a thickness of 100 nm or more and 3000 nm or less, and the wet-plated layer has a thickness of 3 μm or more and 500 μm or less. (Technology 6) The solid electrolytic capacitor according to any one of Technologies 1 to 5, wherein the capacitor element has a convex portion formed at a connection portion between the cathode layer and the cathode terminal. (Technology 7) The solid electrolytic capacitor according to Technology 6, wherein the convex portion has a protruding length of 100 μm or more and 2000 μm or less.(Technology 8) The solid electrolytic capacitor according to any one of Technologies 1 to 7, wherein the at least one anode wire includes a plurality of anode wires. (Technology 9) The solid electrolytic capacitor according to any one of Technologies 1 to 8, wherein the anode wire is formed in a plate shape. (Technology 10) The solid electrolytic capacitor according to any one of Technologies 1 to 9, wherein the at least one capacitor element includes a plurality of capacitor elements, and the anode wire of each of the plurality of capacitor elements is connected to the same metal member. (Technology 11) The solid electrolytic capacitor according to any one of Technologies 1 to 10, wherein the anode wire penetrates the anode body, the at least one metal member includes a first metal member connected to one protruding portion of the anode wire and a second metal member connected to the other protruding portion of the anode wire, and the at least one anode terminal includes a first anode terminal connected to the second lower surface of the first metal member and a second anode terminal connected to the second lower surface of the second metal member. (Technology 12) The solid electrolytic capacitor according to any one of Technologies 1 to 10, wherein the at least one capacitor element includes a first capacitor element and a second capacitor element, the anode wires of which face in opposite directions and protrude outward, the at least one metal member includes a first metal member connected to the anode wire of the first capacitor element and a second metal member connected to the anode wire of the second capacitor element, and the at least one anode terminal includes a first anode terminal connected to the second lower surface of the first metal member and a second anode terminal connected to the second lower surface of the second metal member. (Technology 13) The solid electrolytic capacitor according to any one of Technologies 1 to 10, wherein the at least one capacitor element includes a first capacitor element and a second capacitor element, the anode wires of which face in opposite directions and protrude inward, and the at least one cathode terminal includes a first cathode terminal connected to the cathode layer of the first capacitor element and a second cathode terminal connected to the cathode layer of the second capacitor element.(Technology 14) The solid electrolytic capacitor according to any one of Techniques 1 to 13, wherein the first metal layer and the second metal layer extend across one side of the exterior resin, and the third metal layer and the fourth metal layer extend across another side of the exterior resin. (Technology 15) The solid electrolytic capacitor according to Technique 14, wherein the first metal layer corresponding to one side of the exterior resin is connected to at least one of the anode wire and the metal member. (Technology 16) The solid electrolytic capacitor according to Techniques 14 or 15, wherein the third metal layer corresponding to the other side of the exterior resin is connected to a side of the cathode layer. (Technology 17) A method for manufacturing the solid electrolytic capacitor according to any one of Technologies 1 to 13, comprising: a first step of preparing an adhesive carrier having adhesiveness; a second step of arranging the metal member on the adhesive carrier; a third step of arranging the capacitor element on the adhesive carrier; a fourth step of connecting the anode wire and the metal member; a fifth step of forming the exterior resin on the adhesive carrier so as to cover at least a part of the capacitor element and the metal member; a sixth step of peeling off the adhesive carrier to expose the second lower surface of the metal member and the first lower surface of the cathode layer of the capacitor element from the exterior resin; a seventh step of forming a dry plated layer including portions corresponding to the first metal layer and the third metal layer using a dry plating method; and an eighth step of forming a wet plated layer including portions corresponding to the second metal layer and the fourth metal layer using a wet plating method. and a ninth step of patterning the dry-plated layer and the wet-plated layer to form the first metal layer, the second metal layer, the third metal layer, and the fourth metal layer. (Technology 18) The method for manufacturing a solid electrolytic capacitor according to Technology 17, further comprising a tenth step of forming a sealing resin that covers the cathode layer and at least a part of the exterior resin. (Technology 19) The method for manufacturing a solid electrolytic capacitor according to Technology 18, wherein the tenth step is performed between the sixth step and the seventh step.(Technology 20) The method for manufacturing a solid electrolytic capacitor according to any one of Techniques 17 to 19, further comprising an eleventh step between the sixth step and the seventh step of removing portions of the exterior resin on both sides of the capacitor element.

[0104] While the present invention has been described in terms of presently preferred embodiments, such disclosure is not to be interpreted as limiting. Various changes and modifications will no doubt become apparent to those skilled in the art to which the present invention pertains upon reading the above disclosure. It is therefore intended that the appended claims be interpreted to cover all changes and modifications that do not depart from the true spirit and scope of the invention.

[0105] The present disclosure can be used for a solid electrolytic capacitor and a method for manufacturing a solid electrolytic capacitor.

[0106] 10: Solid electrolytic capacitor 20: Capacitor element 21: Anode body 21a: Side surface 22: Anode wire 22a: Embedded portion 22b: Protruding portion 23: Dielectric layer 24: Solid electrolyte layer 25: Cathode layer 25a: First lower surface 25b: Carbon layer 25c: Metal paste layer 26: Protruding portion 20A: First capacitor element 20B: Second capacitor element 30: Metal member 30a: Second lower surface 30A: First metal member 30B: Second metal member 41: Exterior resin 42: Sealing resin 50: Anode terminal 51: First metal layer 52: Second metal layer 50A: First anode terminal 50B: Second anode terminal 60: Cathode terminal 61: Third metal layer 62: Fourth metal layer 60A: First cathode terminal 60B: Second cathode terminal 70: Dry plated layer 80: Wet plated layer 100: Adhesive carrier 101: Support substrate 102: Adhesive layer

Claims

1. A solid electrolytic capacitor comprising: at least one capacitor element having: a porous anode body having a side surface; at least one anode wire partially embedded in the anode body and the remainder protruding from the side surface; a dielectric layer formed on the surface of the anode body; a solid electrolyte layer covering at least a portion of the dielectric layer; and a cathode layer covering at least a portion of the solid electrolyte layer and having a first lower surface; at least one metal member connected to the anode wire and having a second lower surface; an exterior resin covering at least a portion of the capacitor element and the metal member; at least one anode terminal having a first metal layer connected to the second lower surface and a second metal layer connected to the first metal layer, the anode terminal being exposed from the exterior resin; and at least one cathode terminal having a third metal layer connected to the first lower surface and a fourth metal layer connected to the third metal layer, the cathode terminal being exposed from the exterior resin.

2. The solid electrolytic capacitor according to claim 1, further comprising a sealing resin that covers at least a portion of the cathode layer and the exterior resin at least between the anode terminal and the cathode terminal.

3. The solid electrolytic capacitor according to claim 1 or 2, wherein the first metal layer and the third metal layer are each dry-plated layers, and the second metal layer and the fourth metal layer are each wet-plated layers.

4. The solid electrolytic capacitor according to claim 3, wherein the dry-plated layer contains at least one metal material selected from the group consisting of Ti, Cr, and Ni, and the wet-plated layer contains at least one metal material selected from the group consisting of Cu, Ni, Sn, and Al.

5. The solid electrolytic capacitor according to claim 3, wherein the thickness of the dry-plated layer is 100 nm or more and 3000 nm or less, and the thickness of the wet-plated layer is 3 μm or more and 500 μm or less.

6. The solid electrolytic capacitor according to claim 1 or 2, wherein the capacitor element has a protrusion formed at a connection site between the cathode layer and the cathode terminal.

7. The solid electrolytic capacitor according to claim 6, wherein the protruding length of the convex portion is 100 μm or more and 2000 μm or less.

8. The solid electrolytic capacitor according to claim 1 or 2, wherein the at least one anode wire comprises a plurality of anode wires.

9. The solid electrolytic capacitor according to claim 1 or 2, wherein the anode wire is formed in a plate shape.

10. The solid electrolytic capacitor according to claim 1 or 2, wherein the at least one capacitor element includes a plurality of capacitor elements, and the anode wire of each of the plurality of capacitor elements is connected to the same metal member.

11. The solid electrolytic capacitor according to claim 1 or 2, wherein the anode wire penetrates the anode body, the at least one metal member includes a first metal member connected to one protrusion of the anode wire and a second metal member connected to the other protrusion of the anode wire, and the at least one anode terminal includes a first anode terminal connected to the second lower surface of the first metal member and a second anode terminal connected to the second lower surface of the second metal member.

12. The solid electrolytic capacitor according to claim 1 or 2, wherein the at least one capacitor element includes a first capacitor element and a second capacitor element, the anode wires of which face in opposite directions and protrude outward; the at least one metal member includes a first metal member connected to the anode wire of the first capacitor element and a second metal member connected to the anode wire of the second capacitor element; and the at least one anode terminal includes a first anode terminal connected to the second lower surface of the first metal member and a second anode terminal connected to the second lower surface of the second metal member.

13. The solid electrolytic capacitor according to claim 1 or 2, wherein the at least one capacitor element includes a first capacitor element and a second capacitor element in which the anode wires face inward and point in opposite directions, and the at least one cathode terminal includes a first cathode terminal connected to the cathode layer of the first capacitor element and a second cathode terminal connected to the cathode layer of the second capacitor element.

14. The solid electrolytic capacitor according to claim 1 or 2, wherein the first metal layer and the second metal layer extend across one side of the exterior resin, and the third metal layer and the fourth metal layer extend across another side of the exterior resin.

15. The solid electrolytic capacitor according to claim 14, wherein the first metal layer corresponding to one side of the exterior resin is connected to at least one of the anode wire and the metal member.

16. The solid electrolytic capacitor according to claim 14, wherein the third metal layer corresponding to the other side of the exterior resin is connected to a side of the cathode layer.

17. A method for manufacturing the solid electrolytic capacitor according to claim 1 or 2, comprising: a first step of preparing an adhesive carrier having adhesiveness; a second step of arranging the metal member on the adhesive carrier; a third step of arranging the capacitor element on the adhesive carrier; a fourth step of connecting the anode wire and the metal member; a fifth step of forming the exterior resin on the adhesive carrier so as to cover at least a portion of the capacitor element and the metal member; a sixth step of peeling off the adhesive carrier to expose from the exterior resin the second lower surface of the metal member and the first lower surface of the cathode layer of the capacitor element; a seventh step of forming a dry plating layer using a dry plating method, the dry plating layer including portions corresponding to the first metal layer and the third metal layer; and an eighth step of forming a wet plating layer using a wet plating method, the wet plating layer including portions corresponding to the second metal layer and the fourth metal layer. and a ninth step of patterning the dry-plated layer and the wet-plated layer to form the first metal layer, the second metal layer, the third metal layer, and the fourth metal layer.

18. The method for producing a solid electrolytic capacitor according to claim 17, further comprising a tenth step of forming a sealing resin that covers at least a portion of the cathode layer and the exterior resin.

19. The method for manufacturing a solid electrolytic capacitor according to claim 18, wherein the tenth step is carried out between the sixth step and the seventh step.

20. The method for manufacturing a solid electrolytic capacitor according to claim 17, further comprising an eleventh step between the sixth step and the seventh step, of removing portions of the exterior resin on both sides of the capacitor element.

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