Solid electrolytic capacitor element, capacitor array, and composite electronic component

Abstract

To provide a capacitor array having a high degree of freedom in layout, in which a plurality of solid electrolytic capacitor elements are aggregated into a single array.SOLUTION: A capacitor array according to the present invention includes: a plurality of solid electrolytic capacitor elements formed by dividing one solid electrolytic capacitor sheet; a sheet-shaped first sealing layer; and a sheet-shaped second sealing layer. The solid electrolytic capacitor sheet includes: an anode plate made of a valve-action metal; a porous layer provided on at least one main surface of the anode plate; a dielectric layer provided on a surface of the porous layer; and a cathode layer including a solid electrolyte layer provided on a surface of the dielectric layer. The solid electrolytic capacitor sheet has a first main surface and a second main surface facing each other in a thickness direction. The first main surface side of each of the plurality of solid electrolytic capacitor elements is disposed on the first sealing layer. The second sealing layer is disposed so as to cover the plurality of solid electrolytic capacitor elements on the first sealing layer from the second main surface side. The solid electrolytic capacitor elements are partitioned from each other by a slit-shaped sheet removal portion.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a solid electrolytic capacitor element, a capacitor array, and a composite electronic component. [Background technology]

[0002] Patent Document 1 discloses a solid electrolytic capacitor array comprising a capacitor element group consisting of a plurality of capacitor elements, one or more anode terminals connected to and drawn out from one or more anode lead wires of the capacitor elements in the capacitor element group, one or more cathode terminals connected to and drawn out from cathode layers of the capacitor elements, and an exterior resin layer that covers the capacitor elements, wherein the anode terminals and the cathode terminals are configured as external terminals. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-281750 A Summary of the Invention [Problem to be solved by the invention]

[0004] According to Patent Document 1, by connecting multiple capacitor elements to an anode terminal and a cathode terminal to form an array structure, it is possible to easily manufacture a solid electrolytic capacitor array that achieves low ESR (equivalent series resistance) and low ESL (equivalent series inductance) and has excellent high-frequency characteristics.

[0005] However, when forming an array of multiple capacitor elements using the method described in Patent Document 1, it is necessary to connect pre-formed capacitor elements to each other, which leads to problems such as a tendency for the manufacturing process to become complicated, and a low volumetric capacitance density of the entire capacitor array, etc. Therefore, it cannot be said that the performance for higher frequencies is optimal.

[0006] The present invention has been made to solve the above problems, and aims to provide a capacitor array in which multiple solid electrolytic capacitor elements are integrated into one, allowing for a high degree of freedom in layout. Another aim of the present invention is to provide a composite electronic component in which an electronic component is mounted on the external electrode of the capacitor array. [Means for solving the problem]

[0007] The capacitor array of the present invention includes a plurality of solid electrolytic capacitor elements formed by dividing a single solid electrolytic capacitor sheet, a sheet-like first sealing layer, and a sheet-like second sealing layer. The solid electrolytic capacitor sheet includes an anode plate made of a valve metal, a porous layer provided on at least one main surface of the anode plate, a dielectric layer provided on the surface of the porous layer, and a cathode layer including a solid electrolyte layer provided on the surface of the dielectric layer, and has a first main surface and a second main surface opposed to each other in the thickness direction. The first main surface side of each of the plurality of solid electrolytic capacitor elements is disposed on the first sealing layer. The second sealing layer is disposed so as to cover the plurality of solid electrolytic capacitor elements on the first sealing layer from the second main surface side. The solid electrolytic capacitor elements are divided by a slit-shaped sheet removal portion.

[0008] The composite electronic component of the present invention comprises the capacitor array of the present invention, an external electrode provided on the outside of the first sealing layer or the second sealing layer of the capacitor array and connected to each of the anode plate and the cathode layer of the capacitor array, and an electronic component connected to the external electrode. Effect of the Invention

[0009] According to the present invention, it is possible to provide a capacitor array in which a plurality of solid electrolytic capacitor elements are integrated into one, allowing for a high degree of freedom in layout. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic diagram of an example of a capacitor array of the present invention. [Diagram 2] FIG. 2 is an enlarged cross-sectional view illustrating typically another example of the sheet removing unit. [Diagram 3] FIG. 3A is a perspective view that illustrates an example of a step of preparing a chemical foil, and FIG. 3B is a cross-sectional view thereof. [Figure 4] FIG. 4A is a perspective view that illustrates an example of a step of forming an insulating layer, and FIG. 4B is a cross-sectional view thereof. [Diagram 5] FIG. 5 is a perspective view that illustrates an example of a step of forming a through hole. [Figure 6] FIG. 6A is a perspective view that illustrates an example of a process for forming a solid electrolyte layer, and FIG. 6B is a cross-sectional view thereof. [Figure 7] FIG. 7A is a perspective view that illustrates an example of a step of forming a carbon layer, and FIG. 7B is a cross-sectional view thereof. [Figure 8] FIG. 8A is a perspective view that illustrates an example of a step of forming a copper layer, and FIG. 8B is a cross-sectional view thereof. [Figure 9] FIG. 9A is a perspective view that diagrammatically shows an example of a step of disposing a first sealing layer, and FIG. 9B is a cross-sectional view thereof. [Figure 10] FIG. 10A is a perspective view that illustrates an example of a step of cutting a solid electrolytic capacitor sheet, and FIG. 10B is a cross-sectional view thereof. [Figure 11] FIG. 11 is a perspective view that illustrates an example of a process for arranging a capacitor element of a type different from the solid electrolytic capacitor element. [Figure 12] FIG. 12A is a perspective view that diagrammatically illustrates an example of a step of disposing a second sealing layer, and FIG. 12B is a cross-sectional view thereof. [Figure 13] FIG. 13A is a perspective view that illustrates an example of a process for dividing into a plurality of capacitor arrays, and FIG. 13B is a cross-sectional view thereof. [Figure 14] FIG. 14 is a perspective view that illustrates an example of a process for forming an external anode electrode. [Figure 15] FIG. 15 is a perspective view that illustrates an example of a process for forming an external cathode electrode. [Figure 16] FIG. 16 is a perspective view diagrammatically showing another example of the step of forming a cathode external electrode. [Figure 17] FIG. 17 is a perspective view of FIG. 15 for explaining the function of the through-hole. [Figure 18] FIG. 18 is a perspective view of FIG. 16 for explaining the function of the through-hole. [Figure 19] 19A is a projected plan view of a first modified example of the anode and cathode structures as viewed from the second sealing layer side, and FIG. 19B is a projected cross-sectional view taken along line bb in FIG. 19A. [Figure 20] 20A is a projected plan view of a second modified example of the anode and cathode structure as viewed from the second sealing layer side, and FIG. 20B is a projected cross-sectional view taken along line bb in FIG. 20A. [Figure 21] 21A is a projected plan view of a third modified example of the anode and cathode structure as viewed from the second sealing layer side, and FIG. 21B is a projected cross-sectional view taken along line bb in FIG. 21A. [Figure 22] 22A is a projected plan view of a fourth modified example of the anode and cathode structure as viewed from the second sealing layer side, and FIG. 22B is a projected cross-sectional view taken along line bb in FIG. 22A. [Figure 23] FIG. 23 is a perspective view that illustrates another example of a step of cutting a solid electrolytic capacitor sheet. [Figure 24] FIG. 24 is a plan view that illustrates an example of a capacitance section whose planar shape is not rectangular. [Diagram 25] FIG. 25 is a cross-sectional view illustrating a schematic example of a capacitor array including a stress relieving layer. [Figure 26] FIG. 26 is a perspective view showing a schematic example of a solid electrolytic capacitor sheet for producing the capacitor array shown in FIG. [Figure 27] FIG. 27 is a cross-sectional view illustrating a schematic diagram of another example of a capacitor array including a stress relieving layer. [Figure 28] FIG. 28 is a perspective view showing a schematic example of a solid electrolytic capacitor sheet for producing the capacitor array shown in FIG. [Figure 29] FIG. 29 is a cross-sectional view illustrating a schematic diagram of still another example of a capacitor array including a stress relieving layer. [Diagram 30] FIG. 30 is a perspective view showing typically an example of a solid electrolytic capacitor sheet for producing the capacitor array shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The capacitor array and composite electronic component of the present invention will be described below. However, the present invention is not limited to the following configurations, and can be appropriately modified and applied within the scope of the present invention. Note that the present invention also includes a combination of two or more of the individual preferable configurations of the present invention described below.

[0012] [Capacitor array] The capacitor array of the present invention includes a plurality of solid electrolytic capacitor elements, a sheet-like first sealing layer, and a sheet-like second sealing layer, with the first main surface side of each of the plurality of solid electrolytic capacitor elements being disposed on the first sealing layer, and the second sealing layer being disposed so as to cover the plurality of solid electrolytic capacitor elements on the first sealing layer from the second main surface side.

[0013] The capacitor array of the present invention is characterized in that a plurality of solid electrolytic capacitor elements are originally a single solid electrolytic capacitor sheet, and the solid electrolytic capacitor elements are separated by slit-shaped removed portions of the sheet.

[0014] By forming multiple solid electrolytic capacitor elements collectively from a single sheet, it is possible to inexpensively manufacture capacitor arrays with a high degree of freedom in layout, which allows for flexible support for different wiring paths for individual applications, such as central processing units (CPUs) and power management ICs (PMICs).

[0015] In addition, by changing the size when dividing the solid electrolytic capacitor element, it is possible to arrange solid electrolytic capacitor elements with different characteristics within a capacitor array, which allows the characteristic impedance to be matched over a wide range when connected in parallel.

[0016] In the capacitor array of the present invention, the first and second sealing layers are layers containing sealing resins such as epoxy resins and phenolic resins. It is necessary to control the glass transition temperature Tg and elastic modulus of these sealing layers so that they do not apply stress to the element part during the formation of the capacitor array and during thermal stress loading. Specifically, it is preferable that the sealing layers are highly filled with inorganic fillers such as alumina and silica.

[0017] FIG. 1 is a cross-sectional view illustrating a typical example of a capacitor array of the present invention. The capacitor array 1 shown in FIG. 1 includes a plurality of solid electrolytic capacitor elements 10A, 10B, and 10C, a sheet-like first sealing layer 11, and a sheet-like second sealing layer 12. The solid electrolytic capacitor element 10A has a first main surface S1 and a second main surface S2 that face each other in the thickness direction (the vertical direction in FIG. 1), and the first main surface S1 side is disposed on the first sealing layer 11. The same is true for the solid electrolytic capacitor elements 10B and 10C. The second sealing layer 12 is disposed so as to cover the plurality of solid electrolytic capacitor elements 10A, 10B, and 10C on the first sealing layer 11 from the second main surface S2 side. Therefore, the capacitor array 1 shown in FIG. 1 has a sheet-like shape as a whole.

[0018] In the capacitor array 1 shown in FIG. 1, the solid electrolytic capacitor element 10A includes an anode plate 21, a porous layer 22 provided on at least one of the main surfaces of the anode plate 21, a dielectric layer 23 provided on the surface of the porous layer 22, and a cathode layer 24 provided on the surface of the dielectric layer 23. In FIG. 1, the cathode layer 24 includes a solid electrolyte layer 24a provided on the surface of the dielectric layer 23, a carbon layer 24b provided on the surface of the solid electrolyte layer 24a, and a copper layer 24c provided on the surface of the carbon layer 24b. In FIG. 1, the porous layer 22 and the dielectric layer 23 are provided on both main surfaces of the anode plate 21, and the cathode layer 24 is provided only on the second main surface S2 side, but the cathode layer 24 may be provided only on the first main surface S1 side, or the cathode layer 24 may be provided on both the first main surface S1 side and the second main surface S2 side. The porous layer 22 may be provided on both main surfaces of the anode plate 21, or on either one of the main surfaces. The same applies to the solid electrolytic capacitor elements 10B and 10C.

[0019] The solid electrolytic capacitor elements 10A, 10B, and 10C are originally a single solid electrolytic capacitor sheet 100 (see FIGS. 8A and 8B, etc.). The solid electrolytic capacitor element 10A and the solid electrolytic capacitor element 10B, and the solid electrolytic capacitor element 10B and the solid electrolytic capacitor element 10C are separated by slit-shaped sheet removal portions 25. Therefore, the solid electrolytic capacitor elements 10A, 10B, and 10C have the same configuration. In addition, the distance from the bottom surface of the second sealing layer 12 to the anode plate 21 of each of the solid electrolytic capacitor elements 10A, 10B, and 10C is constant.

[0020] As shown in FIG. 1, it is preferable that second sealing layer 12 extends toward first sealing layer 11, between anode plates 21 of adjacent solid electrolytic capacitor elements on first sealing layer 11, and further extends into a portion of first sealing layer 11. When second sealing layer 12 penetrates into a part of first sealing layer 11, the adhesion between first sealing layer 11 and second sealing layer 12 is improved, and therefore the reliability of capacitor array 1 is improved.

[0021] 1, second sealing layer 12 extends between anode plates 21 of all solid electrolytic capacitor elements adjacent to each other on first sealing layer 11 toward the first sealing layer 11 side, and also extends into part of first sealing layer 11, but there may be a portion of first sealing layer 11 where second sealing layer 12 does not extend. Also, second sealing layer 12 does not have to extend into first sealing layer 11.

[0022] 1, an insulating layer 30 is preferably provided on the surface of the dielectric layer 23 on the second main surface S2 side, on which the cathode layer 24 is not provided, for insulating the anode plate 21 from the cathode layer 24. In FIG. 1, the insulating layer 30 is provided on the surface of the dielectric layer 23 on the first main surface S1 side, but the insulating layer 30 does not necessarily have to be provided on the surface of the dielectric layer 23 on the first main surface S1 side.

[0023] Although not shown in FIG. 1, external electrodes connected to anode plate 21 and cathode layer 24, respectively, are provided on the outside of first sealing layer 11 or second sealing layer 12, as described below.

[0024] Although the form in which the anode plate or cathode layer is connected to the external electrode is not particularly limited, it is preferable that a through electrode is provided that passes through the first sealing layer or the second sealing layer in the thickness direction, and the anode plate or cathode layer is connected to the external electrode via the through electrode. By using the through electrode, the lead distance from the anode plate or cathode layer to the external electrode can be shortened.

[0025] 1, the side surfaces of the solid electrolytic capacitor elements 10A and 10C are exposed, but may be covered with, for example, a first sealing layer or a second sealing layer, or may be covered with an insulating layer. In addition, for example, a stress relaxation layer, a moisture-proof film, etc. may be provided between the solid electrolytic capacitor elements and the first sealing layer or the second sealing layer.

[0026] In the capacitor array of the present invention, the distance between the anode plates of adjacent solid electrolytic capacitor elements on the first sealing layer (D 10The distance between the anode plates of adjacent solid electrolytic capacitor elements on the first sealing layer is preferably 500 μm or less, more preferably 200 μm or less, and even more preferably 150 μm or less, while the distance between the anode plates of adjacent solid electrolytic capacitor elements on the first sealing layer is preferably 500 μm or less, more preferably 200 μm or less, and even more preferably 150 μm or less.

[0027] In the capacitor array of the present invention, the number of solid electrolytic capacitor elements arranged on the first sealing layer is not particularly limited as long as it is two or more. The solid electrolytic capacitor elements may be arranged linearly or planarly on the first sealing layer. The solid electrolytic capacitor elements may be arranged regularly or irregularly on the first sealing layer. The size, shape, etc. of the solid electrolytic capacitor elements may be the same or may be partially or entirely different.

[0028] FIG. 2 is an enlarged cross-sectional view illustrating typically another example of the sheet removing unit. 2 has a taper that narrows in width from the second main surface S2 toward the first main surface S1 of the solid electrolytic capacitor elements 10A and 10B. The taper of the sheet-removed portion 25A does not reach the porous layer 22 on the first main surface S1 side of the solid electrolytic capacitor elements 10A and 10B, and does not reach the anode plate 21.

[0029] In the capacitor array of the present invention, the sheet-removed portion preferably has a taper that decreases in width from one main surface of the solid electrolytic capacitor element to the other main surface of the solid electrolytic capacitor element. The sheet-removed portion may have a taper that decreases in width from the second main surface to the first main surface of the solid electrolytic capacitor element, or may have a taper that decreases in width from the first main surface to the second main surface of the solid electrolytic capacitor element.

[0030] It is preferable that the taper does not reach the anode plate of the solid electrolytic capacitor element. In particular, when the porous layer is provided on both main surfaces of the anode plate, it is preferable that the taper does not reach the porous layer on the other main surface side of the solid electrolytic capacitor element. When the solid electrolytic capacitor element has a taper whose width decreases from the second main surface to the first main surface, it is preferable that the taper does not reach the porous layer on the first main surface side of the solid electrolytic capacitor element. On the other hand, when the solid electrolytic capacitor element has a taper whose width decreases from the first main surface to the second main surface, it is preferable that the taper does not reach the porous layer on the second main surface side of the solid electrolytic capacitor element.

[0031] In the capacitor array of the present invention, the insulating layer is preferably made of a resin. Examples of the resin constituting the insulating layer include insulating resins such as polyphenylsulfone resin, polyethersulfone resin, cyanate ester resin, fluororesin (tetrafluoroethylene, tetrafluoroethylene-perfluoroalkylvinylether copolymer, etc.), polyimide resin, polyamideimide resin, epoxy resin, and derivatives or precursors thereof. The insulating layer may be made of the same resin as the first sealing layer and the second sealing layer. Unlike the first sealing layer and the second sealing layer, if the insulating layer contains an inorganic filler, it may adversely affect the active part of the solid electrolytic capacitor element, so the insulating layer is preferably made of a resin alone.

[0032] In the capacitor array of the present invention, the first sealing layer and the second sealing layer are preferably made of a resin. Examples of the resin constituting the first sealing layer and the second sealing layer include epoxy resin and phenol resin. Furthermore, the first sealing layer and the second sealing layer preferably contain a filler. Examples of the filler contained in the first sealing layer and the second sealing layer include inorganic fillers such as silica particles, alumina particles, and metal particles. The resin constituting the first sealing layer may be the same as or different from the resin constituting the second sealing layer.

[0033] The first sealing layer and the second sealing layer may each be composed of only one layer, or may be composed of two or more layers. The number of layers constituting the first sealing layer may be the same as or different from the number of layers constituting the second sealing layer. When the first sealing layer or the second sealing layer is composed of two or more layers, a through electrode may be provided that passes through each sealing layer present between the anode plate or cathode layer and the external electrode in the thickness direction, and an internal electrode may be provided between each sealing layer, and the anode plate or cathode layer and the external electrode may be connected via the through electrode and the internal electrode.

[0034] In the capacitor array of the present invention, the anode plate of the solid electrolytic capacitor element is made of a valve metal that exhibits a so-called valve action. Examples of the valve metal include simple metals such as aluminum, tantalum, niobium, titanium, and zirconium, and alloys containing these metals. Among these, aluminum or an aluminum alloy is preferred.

[0035] The shape of the anode plate is preferably a flat plate, more preferably a foil. The anode plate may have a porous layer on at least one of its main surfaces, and may have a porous layer on both of its main surfaces. The porous layer is preferably an etching layer formed on the surface of the anode plate.

[0036] The thickness of the anode plate before etching is preferably 60 μm or more and 200 μm or less. The thickness of the core part that is not etched after etching is preferably 15 μm or more and 70 μm or less. The thickness of the porous layer is designed according to the required withstand voltage and electrostatic capacity, but the thickness of the porous layers on both sides of the core part is preferably 10 μm or more and 180 μm or less in total.

[0037] In the capacitor array of the present invention, the dielectric layer of the solid electrolytic capacitor element is provided on the surface of the porous layer. The dielectric layer is formed along the surface of the porous layer to form pores (recesses). The dielectric layer is preferably made of an oxide film of the valve metal. For example, when an aluminum foil is used as the anode plate, the surface of the aluminum foil is anodized in an aqueous solution containing ammonium adipate or the like to form a dielectric layer made of an oxide film.

[0038] The thickness of the dielectric layer is designed according to the required withstand voltage and capacitance, but is preferably 10 nm or more and 100 nm or less.

[0039] In the capacitor array of the present invention, the cathode layer of the solid electrolytic capacitor element is provided on the surface of the dielectric layer. The cathode layer includes a solid electrolyte layer provided on the surface of the dielectric layer. It is preferable that the cathode layer further includes a conductor layer provided on the surface of the solid electrolyte layer.

[0040] Materials constituting the solid electrolyte layer include, for example, conductive polymers such as polypyrroles, polythiophenes, and polyanilines. Among these, polythiophenes are preferred, and poly(3,4-ethylenedioxythiophene), also known as PEDOT, is particularly preferred. The conductive polymer may also contain a dopant such as polystyrene sulfonate (PSS).

[0041] The solid electrolyte layer is formed, for example, by a method of forming a polymerized film of poly(3,4-ethylenedioxythiophene) or the like on the surface of the dielectric layer using a treatment liquid containing a monomer such as 3,4-ethylenedioxythiophene, or a method of applying a dispersion liquid of a polymer such as poly(3,4-ethylenedioxythiophene) to the surface of the dielectric layer and drying it, etc. Note that it is preferable to form the solid electrolyte layer by forming an inner layer that fills the pores (recesses) of the dielectric layer and then forming an outer layer that covers the dielectric layer.

[0042] The solid electrolyte layer can be formed in a predetermined region by applying the above-mentioned treatment liquid or dispersion onto the dielectric layer by sponge transfer, screen printing, dispenser, inkjet printing, etc. The thickness of the solid electrolyte layer is preferably 2 μm or more and 20 μm or less.

[0043] The conductor layer includes at least one of a conductive resin layer and a metal layer. The conductor layer may be only a conductive resin layer or only a metal layer. It is preferable that the conductor layer covers the entire surface of the solid electrolyte layer.

[0044] The conductive resin layer may be, for example, a conductive adhesive layer containing at least one conductive filler selected from the group consisting of a silver filler, a copper filler, a nickel filler, and a carbon filler.

[0045] Examples of the metal layer include a metal plating film and a metal foil. The metal layer is preferably made of at least one metal selected from the group consisting of nickel, copper, silver, and alloys containing these metals as main components. The term "main component" refers to the element component having the largest abundance ratio (wt%).

[0046] The conductive layer includes, for example, a carbon layer provided on the surface of the solid electrolyte layer, and a cathode extraction layer provided on the surface of the carbon layer.

[0047] The carbon layer is provided to electrically and mechanically connect the solid electrolyte layer and the cathode lead layer.

[0048] The carbon layer can be formed in a predetermined area by applying a carbon paste onto the solid electrolyte layer by sponge transfer, screen printing, dispenser, inkjet printing, or the like. The carbon layer is preferably laminated with a cathode lead layer in the next step while the carbon layer is still in a viscous state before drying. The thickness of the carbon layer is preferably 2 μm or more and 20 μm or less.

[0049] The cathode lead layer is, for example, a printed electrode layer. The printed electrode layer can be formed by printing an electrode paste on a carbon layer by sponge transfer, screen printing, spray coating, dispenser, inkjet printing, etc. As the electrode paste, it is preferable to use an electrode paste mainly composed of silver, copper, or nickel. In the case of screen printing, it is also possible to set the thickness of the cathode lead layer to 2 μm or more and 20 μm or less.

[0050] The capacitor array of the present invention is preferably manufactured as follows.

[0051] The method for manufacturing a capacitor array of the present invention includes the steps of preparing a solid electrolytic capacitor sheet having first and second main surfaces facing each other in a thickness direction, arranging a sheet-like first sealing layer on the first main surface side of the solid electrolytic capacitor sheet, cutting the solid electrolytic capacitor sheet in the thickness direction from the second main surface side to divide it into a plurality of solid electrolytic capacitor elements arranged on the first sealing layer, and arranging a sheet-like second sealing layer so as to cover the plurality of solid electrolytic capacitor elements on the first sealing layer from the second main surface side.

[0052] When multiple solid electrolytic capacitor elements are individually disposed on the first sealing layer, it is necessary to provide a clearance between adjacent solid electrolytic capacitor elements, and therefore, as the number of solid electrolytic capacitor elements increases, the proportion occupied by the clearance increases, while the proportion occupied by the effective portion of the solid electrolytic capacitor elements decreases. In contrast, by placing a first sealing layer on the first main surface side of the solid electrolytic capacitor sheet, and then cutting the solid electrolytic capacitor sheet from the second main surface side to divide it into multiple solid electrolytic capacitor elements, a capacitor array in which the effective area of ​​the solid electrolytic capacitor elements accounts for a large proportion can be manufactured.

[0053] An example of each step will be described below.

[0054] First, a solid electrolytic capacitor sheet is prepared as shown in FIGS. 3A, 3B, 4A, 4B, 5, 6A, 6B, 7A, 7B, 8A and 8B.

[0055] FIG. 3A is a perspective view that illustrates an example of a step of preparing a chemical foil, and FIG. 3B is a cross-sectional view thereof. A chemically processed foil 20 of aluminum or the like is prepared as an anode plate 21 having a porous layer 22 on at least one main surface and a dielectric layer 23 on the surface of the porous layer 22. Instead of the chemically processed foil 20, for example, an aluminum foil may be prepared as an anode plate, and a porous layer may be formed by etching the surface of the aluminum foil, and then anodizing may be performed in an aqueous solution containing ammonium adipate or the like to form a dielectric layer made of an oxide film.

[0056] FIG. 4A is a perspective view that illustrates an example of a step of forming an insulating layer, and FIG. 4B is a cross-sectional view thereof. In order to separate the effective portions of the solid electrolytic capacitor elements, an insulating resin is applied onto the dielectric layer 23 to form an insulating layer 30. The method for applying the insulating resin is not particularly limited, and examples include a dispenser and screen printing. In FIG. 4A, an area in which a total of six solid electrolytic capacitor elements, 3 vertically and 2 horizontally, are mounted, constitutes one capacitor array unit.

[0057] FIG. 5 is a perspective view that illustrates an example of a step of forming a through hole. At predetermined positions around the capacitor array unit, through holes 31 are formed penetrating in the thickness direction through chemically formed foil 20 on which insulating layer 30 is formed.

[0058] As described later, a through electrode is formed in the through hole 31. This through electrode is used to connect the anode plate and an external electrode, or to connect the cathode layer and an external electrode. The through electrode may be used to connect the cathode layers formed to sandwich the anode plate. The through electrode may also be used for other connections. As described in [Composite electronic component], the capacitor array of the present invention becomes a composite electronic component by mounting electronic components. In the composite electronic component, the external electrode of the capacitor array and the electronic components are connected in the thickness direction via the through electrode formed in the through hole 31, or electronic components other than the capacitor array are connected in the thickness direction.

[0059] Furthermore, as shown in FIG. 5, a through hole 32 may be formed for arranging a capacitor element of a type different from the solid electrolytic capacitor element.

[0060] FIG. 6A is a perspective view that illustrates an example of a process for forming a solid electrolyte layer, and FIG. 6B is a cross-sectional view thereof. A solid electrolyte layer 24a is formed on the dielectric layer 23. For example, the solid electrolyte layer can be formed by a method of forming a polymer film of poly(3,4-ethylenedioxythiophene) or the like on the surface of the dielectric layer using a treatment liquid containing a monomer such as 3,4-ethylenedioxythiophene, or by applying a dispersion liquid of a polymer such as poly(3,4-ethylenedioxythiophene) to the surface of the dielectric layer and drying it. Note that it is preferable to form the solid electrolyte layer by forming an inner layer that fills the pores of the dielectric layer and then forming an outer layer that covers the dielectric layer.

[0061] FIG. 7A is a perspective view that illustrates an example of a step of forming a carbon layer, and FIG. 7B is a cross-sectional view thereof. The carbon layer 24b is formed on the solid electrolyte layer 24a. For example, the carbon layer can be formed by applying and drying a conductive adhesive paste containing a carbon filler.

[0062] FIG. 8A is a perspective view that illustrates an example of a step of forming a copper layer, and FIG. 8B is a cross-sectional view thereof. A copper layer 24c is formed on the carbon layer 24b. As a result, the cathode layer 24 including the solid electrolyte layer 24a, the carbon layer 24b, and the copper layer 24c is formed on the dielectric layer 23. For example, the copper layer may be formed using a conductive adhesive paste containing a copper filler, or the copper layer may be formed by a copper plating process.

[0063] In this manner, a solid electrolytic capacitor sheet 100 is obtained, which includes an anode plate 21, a porous layer 22 provided on at least one main surface of the anode plate 21, a dielectric layer 23 provided on the surface of the porous layer 22, and a cathode layer 24 provided on the surface of the dielectric layer 23. As shown in Fig. 8B, the solid electrolytic capacitor sheet 100 has a first main surface S1 and a second main surface S2 that face each other in the thickness direction.

[0064] Next, as shown in FIGS. 9A and 9B, a sheet-like first sealing layer is disposed on the first main surface side of the solid electrolytic capacitor sheet.

[0065] FIG. 9A is a perspective view that diagrammatically shows an example of a step of disposing a first sealing layer, and FIG. 9B is a cross-sectional view thereof. The first sealing layer 11 is disposed on the first main surface S1 side of the solid electrolytic capacitor sheet 100. For example, a sheet made of an insulating resin is attached to the solid electrolytic capacitor sheet. The first sealing layer 11 may fill a portion of the through holes 31 and 32.

[0066] 10A and 10B, the solid electrolytic capacitor sheet is cut in the thickness direction from the second main surface side to separate it into a plurality of solid electrolytic capacitor elements arranged on the first sealing layer. Examples of the cutting method include laser processing, dicing processing, and the like.

[0067] FIG. 10A is a perspective view that illustrates an example of a step of cutting a solid electrolytic capacitor sheet, and FIG. 10B is a cross-sectional view thereof. Using the first sealing layer 11 on the first main surface S1 side as a support, the solid electrolytic capacitor sheet 100 is cut in the thickness direction from the second main surface S2 side. At this time, it is preferable that a part of the first sealing layer 11 is also cut. As a result, the solid electrolytic capacitor sheet 100 is divided into solid electrolytic capacitor elements 10A, 10B, 10C, 10D, 10E, and 10F by the slit-shaped sheet removal portion 25 while remaining placed on the first sealing layer 11. Strictly speaking, as shown in FIG. 10A, the capacitor array units are not divided into solid electrolytic capacitor elements in adjacent portions, but each capacitor array unit can be considered to be divided into solid electrolytic capacitor elements 10A, 10B, 10C, 10D, 10E, and 10F.

[0068] The width of the sheet removal portion is not particularly limited, but is preferably 15 μm or more, more preferably 30 μm or more, and even more preferably 50 μm or more. On the other hand, the distance between the anode plates of adjacent solid electrolytic capacitor elements on the first sealing layer is preferably 500 μm or less, more preferably 200 μm or less, and even more preferably 150 μm or less.

[0069] The aspect ratio, which is the ratio of length to width, of the sheet removal portion is preferably equal to or greater than 10, and more preferably equal to or greater than 100. On the other hand, the aspect ratio of the sheet removal portion is preferably equal to or less than 1000.

[0070] FIG. 11 is a perspective view that illustrates an example of a process for arranging a capacitor element of a type different from the solid electrolytic capacitor element. 11, a capacitor element 110 of a type different from the solid electrolytic capacitor element may be disposed in the space formed with the through hole 32. Examples of the capacitor element of a type different from the solid electrolytic capacitor element include a multilayer ceramic capacitor and a silicon capacitor.

[0071] Then, as shown in FIGS. 12A and 12B, a sheet-like second sealing layer is disposed so as to cover the plurality of solid electrolytic capacitor elements on the first sealing layer from the second main surface side.

[0072] FIG. 12A is a perspective view that diagrammatically illustrates an example of a step of disposing a second sealing layer, and FIG. 12B is a cross-sectional view thereof. The second sealing layer 12 is disposed so as to cover the solid electrolytic capacitor elements 10A, 10B, 10C, 10D, 10E, and 10F from the second main surface S2 side. For example, a sheet made of an insulating resin is attached to the solid electrolytic capacitor elements. At this time, the second sealing layer 12 penetrates between the anode plates 21 of the adjacent solid electrolytic capacitor elements on the first sealing layer 11 toward the first main surface S1 side, and further penetrates into a part of the first sealing layer 11.

[0073] FIG. 13A is a perspective view that illustrates an example of a process for dividing into a plurality of capacitor arrays, and FIG. 13B is a cross-sectional view thereof. As shown in FIGS. 13A and 13B, by cutting into capacitor array units, a capacitor array 1 is obtained in which a plurality of solid electrolytic capacitor elements 10A, 10B, 10C, 10D, 10E, and 10F are mounted in one array.

[0074] In the above-described method, a large-sized chemical foil is used and divided into a plurality of capacitor arrays. However, it is also possible to use a chemical foil of a size sufficient for obtaining one capacitor array, thereby eliminating the step of dividing into capacitor arrays.

[0075] In the method of manufacturing a capacitor array of the present invention, it is preferable to arrange the second sealing layer after cutting the solid electrolytic capacitor sheet as in the above-mentioned method. However, it is also possible to arrange a part of the second sealing layer, cut the solid electrolytic capacitor sheet together with the second sealing layer, and then arrange the remaining second sealing layer on the second main surface side.

[0076] In this manner, the capacitor array of the present invention can be manufactured.

[0077] After the capacitor array is fabricated as described above, it is preferable to form external electrodes connected to the anode plate and cathode layer of the capacitor array on the outside of the first sealing layer or the second sealing layer of the capacitor array. For example, external electrodes having a desired pattern can be formed by attaching copper foil and then performing an etching process. Hereinafter, the external electrode connected to the anode plate is also referred to as an anode external electrode, and the external electrode connected to the cathode layer is also referred to as a cathode external electrode.

[0078] FIG. 14 is a perspective view that illustrates an example of a process for forming an external anode electrode. 14, anode external electrodes 41A, 41B, 41C, 41D, 41E, and 41F are formed for each anode plate 21 on the outside of second sealing layer 12. As shown in FIG 14, anode external electrode 41B may be formed so as to connect solid electrolytic capacitor element 10B and capacitor element 110 in parallel.

[0079] FIG. 15 is a perspective view that illustrates an example of a process for forming an external cathode electrode. 15, cathode external electrodes 42A, 42B, 42C, and 42D are formed on the outside of the second sealing layer 12. The cathode external electrode 42A is commonly connected to the cathode layers 24 of the solid electrolytic capacitor elements 10A and 10B, and the cathode external electrode 42C is commonly connected to the cathode layers 24 of the solid electrolytic capacitor elements 10D and 10E. A cathode external electrode may be formed for each cathode layer.

[0080] FIG. 16 is a perspective view diagrammatically showing another example of the step of forming a cathode external electrode. 16, cathode external electrodes 42A and 42B are formed on the outside of the second sealing layer 12. The cathode external electrode 42A is commonly connected to the cathode layers 24 of the solid electrolytic capacitor elements 10A, 10B, 10D, and 10E, and the cathode external electrode 42B is commonly connected to the cathode layers 24 of the solid electrolytic capacitor elements 10C and 10F.

[0081] Although not shown, it is preferable to form a through electrode penetrating the second sealing layer (or the first sealing layer) in the thickness direction, and connect the anode plate and the anode external electrode, and connect the cathode layer and the cathode external electrode via the through electrode. There are no particular limitations on the method for forming the through electrode, and examples include a method in which the anode external electrode and the cathode external electrode are formed and then laser via processing is performed. In addition, the through electrode may be formed before disposing the first sealing layer or the second sealing layer, or may be formed after disposing the first sealing layer or the second sealing layer and before forming the anode external electrode and the cathode external electrode.

[0082] Fig. 17 is a perspective view of Fig. 15 for explaining the function of the through-hole. Fig. 18 is a perspective view of Fig. 16 for explaining the function of the through-hole. 17 and 18, through hole 31X is used to connect the anode plate and an external electrode, through hole 31Y is used to connect the cathode layer and an external electrode, and through hole 31Z is used for connections other than the capacitor.

[0083] The anode external electrode and the cathode external electrode may be formed simultaneously or separately.

[0084] Modified examples of the anode and cathode structures will be described below with reference to the drawings. In the following drawings, only the characteristic configurations are shown, and configurations such as the dielectric layer, solid electrolyte layer, and insulating layer are omitted.

[0085] 19A is a projected plan view of a first modified example of the anode and cathode structures as viewed from the second sealing layer side, and FIG. 19B is a projected cross-sectional view taken along line bb in FIG. 19A.

[0086] The capacitor array 1A shown in FIGS. 19A and 19B includes a line conductor 50, an anode through electrode 51 penetrating the first sealing layer 11 and the second sealing layer 12 in the thickness direction, an anode via conductor 52 penetrating the second sealing layer 12 in the thickness direction, an anode wiring pattern 53 provided on the outside of the second sealing layer 12, and an anode wiring pattern 54 provided on the outside of the first sealing layer 11. In the capacitor array 1A shown in FIGS. 19A and 19B, a part of the porous layer 22 is removed in a line shape, and the line conductor 50 is provided in the removed part. Then, an anode via conductor 52 is provided directly above the line conductor 50, and an anode wiring pattern 53 is provided directly above the anode via conductor 52. The anode plate 21 is electrically connected to the anode through electrode 51 via the line conductor 50, the anode via conductor 52, and the anode wiring pattern 53.

[0087] 19A and 19B further includes a cathode through electrode 61 penetrating first sealing layer 11 and second sealing layer 12 in the thickness direction, a cathode via conductor 62 penetrating second sealing layer 12 in the thickness direction, a cathode wiring pattern 63 provided on the outside of second sealing layer 12, and a cathode wiring pattern 64 provided on the outside of first sealing layer 11. The cathode via conductor 62 is provided directly on the cathode layer 24, and the cathode wiring pattern 63 is provided directly on the cathode via conductor 62. The cathode layer 24 is electrically connected to the cathode through electrode 61 via the cathode via conductor 62 and the cathode wiring pattern 63.

[0088] As shown in FIG. 19A, the anodes X and cathodes Y are preferably arranged in a staggered line shape.

[0089] 20A is a projected plan view of a second modified example of the anode and cathode structure as viewed from the second sealing layer side, and FIG. 20B is a projected cross-sectional view taken along line bb in FIG. 20A.

[0090] The capacitor array 1B shown in Figures 20A and 20B has a similar configuration to the capacitor array 1A shown in Figures 19A and 19B, except that the line conductor 50 is located on the same line as the anode through electrode 51. The anode wiring pattern 53 is omitted in Figure 20A, and the anode via conductor 52 is omitted in Figure 20B.

[0091] As shown in FIG. 20A, the anodes X and cathodes Y are preferably arranged in a staggered line shape.

[0092] 21A is a projected plan view of a third modified example of the anode and cathode structure as viewed from the second sealing layer side, and FIG. 21B is a projected cross-sectional view taken along line bb in FIG. 21A.

[0093] Capacitor array 1C shown in Figures 21A and 21B has a similar configuration to capacitor array 1A shown in Figures 19A and 19B, except that it has via conductors 50A instead of line conductors 50. In capacitor array 1C shown in Figures 21A and 21B, openings are formed in parts of porous layer 22, and via conductors 50A are provided in the openings. Capacitor array 1C shown in Figures 21A and 21B can save space compared to capacitor array 1A shown in Figures 19A and 19B.

[0094] As shown in FIG. 21A, the anodes X and cathodes Y are preferably arranged in a staggered line shape.

[0095] 22A is a projected plan view of a fourth modified example of the anode and cathode structure as viewed from the second sealing layer side, and FIG. 22B is a projected cross-sectional view taken along line bb in FIG. 22A.

[0096] 22A and 22B, the anode plate 21 is directly connected to the wall surface of the anode through electrode 51. Therefore, the capacitor array 1D shown in Figures 22A and 22B can save space.

[0097] As shown in FIG. 22A, the anodes X and cathodes Y are preferably arranged in a staggered pattern.

[0098] As described above, in the capacitor array of the present invention, when viewed from the first sealing layer side or the second sealing layer side, it is possible to arrange the anodes and cathodes in a staggered line pattern or in a staggered check pattern.

[0099] In the capacitor array of the present invention, the anode may be led out and connected to the anode through electrode from either the main surface direction or the end surface direction.

[0100] As described above, when manufacturing the capacitor array of the present invention, the method of cutting the solid electrolytic capacitor sheet includes laser processing, dicing processing, etc. Among them, by cutting the solid electrolytic capacitor sheet using laser processing, the solid electrolytic capacitor elements can be formed into any shape. Therefore, it is possible to arrange two or more types of solid electrolytic capacitor elements with different areas of the capacitance part in one capacitor array, arrange the sheet removal part so as not to cover the entire capacitor array, arrange solid electrolytic capacitor elements whose planar shape of the capacitance part is not rectangular, etc.

[0101] FIG. 23 is a perspective view that illustrates another example of a step of cutting a solid electrolytic capacitor sheet. In Fig. 23, the shape of the divided solid electrolytic capacitor elements is different from that in Fig. 10A. In the example shown in Fig. 23, the solid electrolytic capacitor elements 10A, 10B, and 10C having different capacitance areas are divided by sheet removal portion 25. In Fig. 23, solid electrolytic capacitor element 10C is disposed on an extension of sheet removal portion 25 that separates solid electrolytic capacitor elements 10A and 10B.

[0102] In this manner, in the capacitor array of the present invention, at least a portion of the sheet removal portion may be positioned so as not to overlap the entire capacitor array.

[0103] In the capacitor array of the present invention, at least one solid electrolytic capacitor element may be disposed on the extension of the sheet removed portion.

[0104] The capacitor array of the present invention may contain two or more types of solid electrolytic capacitor elements having capacitive portions with different areas.

[0105] The capacitor array of the present invention may include a solid electrolytic capacitor element whose planar shape of the capacitance part is not rectangular. In this specification, "rectangle" means a square or a rectangle. Therefore, the capacitor array of the present invention may include, for example, a solid electrolytic capacitor element whose planar shape of the capacitance part is a polygon such as a quadrangle, a triangle, a pentagon, a hexagon, or a shape including a curved part, a circle, an ellipse, or the like. In this case, two or more types of solid electrolytic capacitor elements whose planar shapes of the capacitance part are different may be included. In addition to the solid electrolytic capacitor element whose planar shape of the capacitance part is not rectangular, a solid electrolytic capacitor element whose planar shape of the capacitance part is rectangular may or may not be included.

[0106] FIG. 24 is a plan view that illustrates an example of a capacitance section whose planar shape is not rectangular. The capacitive section 70 shown in Fig. 24 has a non-rectangular outer shape and has a through hole 71 formed therein. The above-mentioned through electrode can be formed inside the through hole 71. In Fig. 24, insulating sections 72 are provided on the outer and inner wall surfaces of the capacitive section 70.

[0107] As described above, the capacitor array of the present invention may further include a stress relaxation layer between the solid electrolytic capacitor element and the first sealing layer or the second sealing layer. In this case, the stress relaxation layer may be provided at least either between the solid electrolytic capacitor element and the first sealing layer or between the solid electrolytic capacitor element and the second sealing layer.

[0108] When the capacitor array of the present invention includes a stress relaxation layer, the stress relaxation layer may also be provided in the sheet removal portion, in other words, the stress relaxation layer may also be provided between adjacent solid electrolytic capacitor elements.

[0109] By providing the stress relaxation layer in the above-mentioned location, it is possible to relax the stress occurring between the inside and outside of the capacitor array without impairing the capabilities (resistance, blocking performance, etc.) required for each of the conductor and insulating parts arranged at the outermost part of the solid electrolytic capacitor element, or the capabilities required for the sealing layer (easy adhesion to wiring, easy to form smoothly, etc.) In particular, when the in-plane layout is different (for example, when the shape of the solid electrolytic capacitor element is asymmetric within the main surface or with the other main surface), it is also possible to relax the stress in the surface direction by providing a stress relaxation layer so that the thermal characteristics are different only in one part.

[0110] Fig. 25 is a cross-sectional view showing an example of a capacitor array having a stress relaxation layer. Fig. 26 is a perspective view showing an example of a solid electrolytic capacitor sheet for manufacturing the capacitor array shown in Fig. 25. For convenience, Fig. 26 shows that only one capacitor array is provided with a stress relaxation layer. Fig. 25 corresponds to a cross section of the solid electrolytic capacitor sheet shown in Fig. 26 taken along the arrow.

[0111] 25 includes stress relaxation layers 13 between solid electrolytic capacitor elements 10A, 10B, 10C and first sealing layer 11, and between solid electrolytic capacitor elements 10A, 10B, 10C and second sealing layer 12. In the capacitor array 1E shown in Fig. 25, the stress relaxation layer 13 is provided so as to cover the entire insulating layer 30. Furthermore, the stress relaxation layer 13 fills in the sheet removal portion 25.

[0112] Although not shown in Fig. 26, stress relaxation layer 13 is also provided between solid electrolytic capacitor elements 10D, 10E, 10F and first sealing layer 11. By disposing second sealing layer 12 from the state shown in Fig. 26, stress relaxation layer 13 is also provided between solid electrolytic capacitor elements 10D, 10E, 10F and second sealing layer 12. Through hole 31 shown in Fig. 26 may or may not be filled with stress relaxation layer 13.

[0113] Fig. 27 is a cross-sectional view showing a schematic diagram of another example of a capacitor array having a stress relaxation layer. Fig. 28 is a perspective view showing a schematic diagram of an example of a solid electrolytic capacitor sheet for manufacturing the capacitor array shown in Fig. 27. For convenience, Fig. 28 shows that a stress relaxation layer is provided only on one capacitor array. Fig. 27 corresponds to a cross section taken along the arrow of the solid electrolytic capacitor sheet shown in Fig. 28.

[0114] 27 includes stress relaxation layers 13 between the solid electrolytic capacitor elements 10A, 10B, 10C and the first sealing layer 11, and between the solid electrolytic capacitor elements 10A, 10B, 10C and the second sealing layer 12. In the capacitor array 1F shown in Fig. 27, the stress relaxation layers 13 are provided so as to cover not only the entire insulating layer 30 but also the entire solid electrolytic capacitor elements 10A, 10B, 10C. Furthermore, the stress relaxation layers 13 are filled in the sheet removal portions 25.

[0115] Although not shown in Fig. 28, stress relaxation layer 13 is also provided between solid electrolytic capacitor elements 10D, 10E, 10F and first sealing layer 11. By disposing second sealing layer 12 from the state shown in Fig. 28, stress relaxation layer 13 is also provided between solid electrolytic capacitor elements 10D, 10E, 10F and second sealing layer 12. Through hole 31 shown in Fig. 28 may or may not be filled with stress relaxation layer 13.

[0116] Fig. 29 is a cross-sectional view showing a schematic diagram of yet another example of a capacitor array having a stress relaxation layer. Fig. 30 is a perspective view showing a schematic diagram of an example of a solid electrolytic capacitor sheet for manufacturing the capacitor array shown in Fig. 29. For convenience, in Fig. 30, a stress relaxation layer is provided on only one capacitor array. Fig. 29 corresponds to a cross section taken along the arrow of the solid electrolytic capacitor sheet shown in Fig. 30.

[0117] 29, stress relaxation layers 13 are provided only in a portion of capacitor array 1G. Capacitor array 1G shown in Fig. 29 includes stress relaxation layers 13 between solid electrolytic capacitor elements 10B, 10C and first sealing layer 11, and between solid electrolytic capacitor elements 10A, 10C and second sealing layer 12. Furthermore, stress relaxation layers 13 are filled in sheet removal portions 25.

[0118] 30, the stress relaxation layer 13 may or may not be provided between at least one of the solid electrolytic capacitor elements 10D, 10E, and 10F and the first sealing layer 11. The stress relaxation layer 13 may or may not be provided between at least one of the solid electrolytic capacitor elements 10D, 10E, and 10F and the second sealing layer 12. The through hole 31 shown in FIG. 30 may or may not be filled with the stress relaxation layer 13.

[0119] For example, when the shape of a solid electrolytic capacitor element is asymmetric within a principal surface or with respect to the other principal surface, the thermal stress of the entire capacitor array can be balanced by providing a stress relief layer 13 only in a portion of the capacitor array, as in the capacitor array 1G shown in FIG.

[0120] In the capacitor array of the present invention, the stress relaxation layer is preferably made of an insulating resin. Examples of the insulating resin constituting the stress relaxation layer include epoxy resin, phenolic resin, and silicone resin. Furthermore, the stress relaxation layer preferably contains a filler. Examples of the filler contained in the stress relaxation layer include inorganic fillers such as silica particles, alumina particles, and metal particles. The insulating resin constituting the stress relaxation layer is preferably different from the resin constituting the first sealing layer and the second sealing layer.

[0121] Since the first and second sealing layers are required to have properties such as adhesion to the external electrodes as an exterior body, it is difficult to simply match the linear expansion coefficient with that of the solid electrolytic capacitor element or to select a resin with an arbitrary elastic modulus. In contrast, by providing a stress relaxation layer, it is possible to adjust the thermal stress design without losing the functions of the solid electrolytic capacitor element, the first sealing layer, and the second sealing layer.

[0122] The stress relaxation layer preferably has lower moisture permeability than at least one of the first sealing layer and the second sealing layer. In this case, in addition to adjusting the stress, it is possible to reduce the intrusion of moisture into the solid electrolytic capacitor element. The moisture permeability of the stress relaxation layer can be adjusted by the type of insulating resin constituting the stress relaxation layer, the amount of filler contained in the stress relaxation layer, etc.

[0123] In the capacitor array of the present invention, when a stress relaxation layer is provided between the solid electrolytic capacitor element and the first sealing layer, it is sufficient that the stress relaxation layer is provided between at least one solid electrolytic capacitor element and the first sealing layer. The stress relaxation layer does not have to be provided over the entire area between the solid electrolytic capacitor element and the first sealing layer, and there may be a portion between the solid electrolytic capacitor element and the first sealing layer where the stress relaxation layer is not provided.

[0124] In the capacitor array of the present invention, when a stress relaxation layer is provided between the solid electrolytic capacitor element and the second sealing layer, it is sufficient that the stress relaxation layer is provided between at least one solid electrolytic capacitor element and the second sealing layer. The stress relaxation layer does not have to be provided over the entire area between the solid electrolytic capacitor element and the second sealing layer, and there may be a portion between the solid electrolytic capacitor element and the second sealing layer where the stress relaxation layer is not provided.

[0125] In the capacitor array of the present invention, when a stress relaxation layer is provided between the solid electrolytic capacitor element and the first sealing layer and between the solid electrolytic capacitor element and the second sealing layer, the stress relaxation layer may be provided between at least one solid electrolytic capacitor element and the first sealing layer and between at least one solid electrolytic capacitor element and the second sealing layer. There may be a solid electrolytic capacitor element in which the stress relaxation layer is provided only on the first sealing layer side, a solid electrolytic capacitor element in which the stress relaxation layer is provided only on the second sealing layer side, or a solid electrolytic capacitor element in which the stress relaxation layer is provided both on the first sealing layer side and the second sealing layer side. The stress relaxation layer does not have to be provided over the entire area between the solid electrolytic capacitor element and the first or second sealing layer, and there may be a portion between the solid electrolytic capacitor element and the first or second sealing layer where the stress relaxation layer is not provided.

[0126] In the capacitor array of the present invention, when a stress relaxation layer is provided in the sheet removal portion, it is sufficient that the stress relaxation layer is provided in at least one sheet removal portion. The stress relaxation layer is preferably filled in the sheet removal portion. Furthermore, it is preferable that the stress relaxation layer penetrates into a part of the first sealing layer.

[0127] [Composite electronic components] The composite electronic component of the present invention comprises a capacitor array of the present invention, external electrodes provided on the outside of the first sealing layer or the second sealing layer of the capacitor array and connected to each of the anode plate and cathode layer of the capacitor array, and an electronic component connected to the external electrodes.

[0128] In the composite electronic component of the present invention, the electronic component connected to the external electrode may be a passive element or an active element. Both the passive element and the active element may be connected to the external electrode, or either the passive element or the active element may be connected to the external electrode. Also, a composite of the passive element and the active element may be connected to the external electrode.

[0129] Examples of passive elements include inductors, etc. Examples of active elements include memories, GPUs (Graphical Processing Units), CPUs (Central Processing Units), MPUs (Micro Processing Units), and PMICs (Power Management ICs).

[0130] As described above, the capacitor array of the present invention has a sheet-like shape as a whole. Therefore, in the composite electronic component of the present invention, the capacitor array can be treated like a mounting board, and electronic components can be mounted on the capacitor array. Furthermore, by making the electronic components to be mounted on the capacitor array into a sheet-like shape, it is also possible to connect the capacitor array and the electronic components in the thickness direction via through electrodes that penetrate each electronic component in the thickness direction. As a result, the active elements and passive elements can be configured like a single module.

[0131] For example, a switching regulator can be formed by electrically connecting the capacitor array of the present invention between a voltage regulator including a semiconductor active element and a load to which the converted DC voltage is supplied.

[0132] In the composite electronic component of the present invention, a circuit layer may be formed on either side of a capacitor matrix sheet on which a plurality of capacitor arrays of the present invention are laid out, and the capacitors may be connected to passive elements or active elements.

[0133] Alternatively, the capacitor array of the present invention may be placed in a cavity previously provided in a substrate, embedded in resin, and then a circuit layer may be formed on the resin. Other passive and active components may be mounted in other cavities in the same substrate.

[0134] Alternatively, the capacitor array of the present invention may be mounted on a smooth carrier such as a wafer or glass, an outer layer made of resin may be formed, a circuit layer may be formed, and then connected to passive or active elements. [Explanation of symbols]

[0135] 1,1A,1B,1C,1D,1E,1F,1G Capacitor array 10A, 10B, 10C, 10D, 10E, 10F Solid electrolytic capacitor elements 11 First sealing layer 12 Second sealing layer 13 Stress relief layer 20 Chemical foil 21 Anode plate 22 Porous layer 23 Dielectric layer 24 Cathode layer 24a Solid electrolyte layer 24b Carbon layer 24c copper layer 25,25A Sheet removal section 30 Insulating layer 31,31X,31Y,31Z,32 Through hole 41A,41B,41C,41D,41E,41F Anode external electrode 42A,42B,42C,42D Cathode external electrode 50 Line Conductor 50A via conductor 51 Anode through electrode 52 Anode via conductor 53,54 Anode wiring pattern 61 Cathode through electrode 62 Cathode via conductor 63,64 Cathode wiring pattern 70 Capacity part 71 Through hole 72 Insulation 100 Solid electrolytic capacitor sheet 110 Solid electrolytic capacitor elements and other types of capacitor elements S1 First main surface S2 2nd main surface D 10 Anode Plate Spacing X Anode Y cathode

Claims

1. an anode plate having a first main surface and a second main surface opposed to each other in a thickness direction and made of a valve metal; a porous layer provided on at least one main surface of the anode plate; a dielectric layer provided on a surface of the porous layer; a cathode layer including a solid electrolyte layer provided on a surface of the dielectric layer; A stress relief layer, A solid electrolytic capacitor element, wherein, in a plan view of the first main surface, at least a portion of the stress relaxation layer overlaps with the anode plate, and at least a portion of the stress relaxation layer does not overlap with the cathode layer.

2. The solid electrolytic capacitor element according to claim 1 , wherein at least a portion of the cathode layer overlaps with the stress relaxation layer in a plan view of the first main surface.

3. The solid electrolytic capacitor element according to claim 1 , wherein at least a portion of the cathode layer does not overlap the stress relaxation layer in a plan view of the first main surface.

4. an insulating layer provided on a surface of the dielectric layer in an area where the cathode layer is not provided, 4. The solid electrolytic capacitor element according to claim 1, wherein the stress relaxation layer has a higher filler content than the insulating layer.

5. 5. The solid electrolytic capacitor element according to claim 1, wherein the stress relaxation layer contains a resin.

6. The solid electrolytic capacitor element according to claim 1, wherein the stress relaxation layer contains a filler.

7. a first sealing layer covering the solid electrolytic capacitor element from the first main surface side; 7. The solid electrolytic capacitor element according to claim 1, further comprising a second sealing layer covering the solid electrolytic capacitor element from the second main surface side.

8. The solid electrolytic capacitor element according to claim 7 , wherein the stress relaxation layer has a lower moisture permeability than at least one of the first sealing layer and the second sealing layer.

9. A single solid electrolytic capacitor sheet is divided into a plurality of solid electrolytic capacitor elements, The solid electrolytic capacitor element is a solid electrolytic capacitor element according to any one of claims 1 to 8, The solid electrolytic capacitor elements are separated by slit-shaped sheet removal portions.

10. The capacitor array according to claim 9 , wherein the stress relief layer is also provided in the sheet removal portion.

11. 11. The capacitor array according to claim 9, wherein the sheet-removed portion has a taper whose width decreases from one main surface of the solid electrolytic capacitor element to the other main surface of the solid electrolytic capacitor element.

12. the porous layer is provided on both main surfaces of the anode plate, 12. The capacitor array of claim 11, wherein the taper does not reach the porous layer on the other main surface side of the solid electrolytic capacitor element.

13. A capacitor array according to any one of claims 9 to 12, an external electrode provided outside the capacitor array and connected to each of the anode plate and the cathode layer of the capacitor array; and an electronic component connected to the external electrode.

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