JP4810456B2 - Chip-type solid electrolytic capacitor and manufacturing method thereof - Google Patents

Description

  The present invention relates to a chip-type solid electrolytic capacitor and a method for manufacturing the same. In particular, the present invention relates to a chip-type solid electrolytic capacitor having a side electrode provided with external connection terminals on both sides and a method for manufacturing the same.

The side electrode chip type solid electrolytic capacitor has an anode terminal and a cathode terminal on the side surface of the capacitor. The capacitor element in which one end of the anode lead is embedded is formed on the outermost cathode layer opposite to the anode lead. In addition to being connected to the cathode terminal via a conductive adhesive, it was connected to the anode terminal in a direction perpendicular to the lead-out direction of the anode lead, and the capacitor element was covered with an exterior made of an insulating resin or the like (Patent Document) 1).
JP 2000-348975 A

  The problem to be solved is when manufacturing a capacitor with a large number of side electrodes at the same time, and when the plating layer is cut to form the side electrodes of individual capacitors, damaged parts such as the cut parts are likely to occur. This is the point to prevent this.

The present invention includes an anode sintered body formed by embedding one end of a valve action metal anode lead, press-pressing a powder obtained by mixing a binder into a fine powder of a valve action metal, and sintering the powder. A capacitor element in which an anodized film, a solid electrolyte layer, and a cathode layer are sequentially provided on the sintered body, an anode side-plated terminal plate connected to the anode lead directly or via a lead metal, and the cathode layer A solid electrolytic capacitor having a cathode side surface terminal plate connected to a side surface thereof by a conductive adhesive, and an exterior resin that encloses the capacitor element and separates the anode side surface terminal plate and the cathode side surface terminal plate, A chip-type solid electrolytic capacitor, wherein a side surface of an anode side plating terminal plate or a side surface of the anode side plating terminal plate and a side surface of the cathode side terminal plate are formed by etching. It is to provide a service.
Further, the present invention includes a step of disposing a metal plate on the bottom surface side of a container with an open top surface, and embedding one end of a valve action metal anode lead above the metal plate, to form a fine powder of valve action metal, An anode sintered body formed by press-pressing and sintering a powder mixed with a binder, and a sintered body, and a capacitor element in which the anodized film, a solid electrolyte layer, and a cathode layer are sequentially provided on the sintered body, A step of hanging the anode lead side upward, and a conductive adhesive provided on a surface of the cathode layer opposite to the anode lead side or at a predetermined position of the metal plate, And the step of solidifying the cathode layer, the step of filling the container with an insulation resin for exterior so that the cathode layer is buried, the insulation for exterior while cutting the anode lead side in the middle Electrically connected to the anode lead side on the resin surface A step of providing a plating layer for an anode side plating terminal plate to be connected; a step of etching an adjacent region of the capacitor element of the plating layer; and a step of cutting an adjacent region of the capacitor element on the metal plate; It is providing the manufacturing method of the chip-type solid electrolytic capacitor which has this.
Further, the present invention includes a step of disposing a metal plate on the bottom surface side of a container with an open top surface, and embedding one end of a valve action metal anode lead above the metal plate, to form a fine powder of valve action metal, An anode sintered body formed by press-pressing and sintering a powder mixed with a binder, and a sintered body, and a capacitor element in which the anodized film, a solid electrolyte layer, and a cathode layer are sequentially provided on the sintered body, A step of hanging the anode lead side upward, and a conductive adhesive provided on a surface of the cathode layer opposite to the anode lead side or at a predetermined position of the metal plate, And the step of solidifying the cathode layer, the step of filling the container with an insulation resin for exterior so that the cathode layer is buried, the insulation for exterior while cutting the anode lead side in the middle Electrically connected to the anode lead side on the resin surface A step of providing a plating layer for the anode side plating terminal plate to be connected, a step of removing from the container, providing an etching resist mask on both sides, and etching an adjacent region of the capacitor element of the plating layer, and on the metal plate And a step of cutting adjacent regions of the capacitor element.

The chip-type solid electrolytic capacitor of the present invention is provided with a plating layer for an anode side plating terminal board or a metal for a cathode side terminal board before cutting adjacent regions of a capacitor element of an exterior insulating resin filled in a container. Since the plate is removed as much as possible by etching in the adjacent region of the capacitor element, it is possible to prevent the cutting portion from being generated in the subsequent mechanical cutting step.

The anode lead described in the present invention is made of a valve action metal such as linear or strip-shaped tantalum or niobium, and is led out from one end face of the anode sintered body.
As the conductive adhesive described in the present invention, a general adhesive can be used. For example, a conductive binder such as gold, silver, copper, nickel or carbon is dispersed in a binder made of an organic substance, and conductivity is obtained after solidification. It is what
The cathode side surface terminal plate described in the present invention may be made of copper, iron, zinc, nickel, or an alloy thereof having a thickness of about 50 μm to 500 μm, and may be plated with nickel, zinc, tin, or the like. Examples of alloys include brass and 42 alloy, and examples of plating include tin and tin. Any metal can be selected which is rich in workability such as ductility and has good plating properties such as solder and tin, and good connectivity with the conductive paste.
The anode side plating terminal plate described in the present invention is a terminal plate provided on the side surface on the anode side of the capacitor, and is formed by plating having a thickness of about 50 μm to 500 μm. You may comprise only an electroless-plating layer. The side surface of the anode side plating terminal plate is formed by etching. Alternatively, the vicinity of the corner portion between the side surface of the anode side plating terminal plate and the outer surface thereof may be formed by etching, and the subsequent portion may be formed by cutting.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view of a chip-type solid electrolytic capacitor according to the present invention.

  Reference numeral 1 denotes a capacitor element, in which one end of an anode lead 2 made of a valve action metal wire or strip thin plate is embedded, and a powder obtained by mixing a binder with a fine powder of the valve action metal is press-press molded, A sponge-like anode sintered body formed by sintering in vacuum, an anodized film on the sintered body, a solid electrolyte layer such as manganese dioxide or a conductive polymer, and a cathode layer of a carbon layer or a silver layer Are sequentially provided. The solid electrolyte is provided on the surface of the anodic oxide film, and manganese dioxide or a conductive polymer can be used as the material. As the conductive polymer, in addition to polythiophene obtained by chemical oxidative polymerization of a thiophene monomer, for example, polypyrrole or polyaniline can be used. The forming method is not limited to chemical oxidative polymerization, and can be formed by electrolytic oxidative polymerization.

Reference numeral 3 denotes a cathode side surface terminal plate made of copper, iron, zinc, nickel, or an alloy thereof having a thickness of about 50 μm to 500 μm or plated with nickel, zinc, tin or the like. Examples of alloys include brass and 42 alloy, and examples of plating include tin and tin. Any metal can be selected which has excellent workability such as ductility and good plating properties such as solder and tin. The conductive adhesive 4 is electrically connected to the end face of the capacitor element opposite to the anode lead 2 side. The inner surface of the cathode side surface terminal plate may be a flat surface. However, it is preferable that the inner surface of the cathode side surface terminal plate has irregularities of about several tens of μm because the mechanical connection with the end face of the capacitor element is good.
Further, protrusion-shaped guides can be provided on the four sides around the inner surface of the cathode side surface terminal plate so that the capacitor element end surface side opposite to the anode lead 2 side can be accommodated in the center of the cathode side surface terminal plate. For the protruding guide, a resin similar to the exterior resin can be used.

  A lead metal 5 is electrically connected to the anode lead 2 by welding or the like. It consists of a plate material or a wire material, copper, iron, zinc, nickel, or alloys thereof, or those plated with nickel, zinc, tin or the like. Examples of alloys include brass and 42 alloy, and examples of plating include tin and tin. Any metal can be selected which has excellent workability such as ductility and good plating properties such as solder and tin. In FIG. 1, the lead metal 5 is an example of a plate material, but a through hole 6 may be provided in a connection portion with the anode lead 2 so that the tip of the anode lead 2 can be easily cut. The lead metal 5 is not always necessary, but for this purpose, it is necessary to make the surface of the anode lead 2 easy to be plated, such as removal of an oxide film by plasma treatment or thermal spraying of a metal that can be easily plated. .

  7 is an exterior resin, and a general sealing material such as an epoxy resin is used. In particular, a material having a low viscosity is preferable from the viewpoint of easy resin filling.

Reference numeral 8 denotes an anode side plating terminal plate made of a planar plated metal having a thickness of about 50 μm to 500 μm. Generally, it forms with the electroplating layer 10 which provided the electroless-plating layer 9 in the foundation | substrate. You may comprise only the electroless-plating layer 9. FIG. The side surface of the anode side plating terminal plate 8 is formed by etching. In particular, the vicinity of the corner between the side surface of the anode side plating terminal plate 8 and the outer surface thereof may be formed by etching, and the subsequent portion may be formed by cutting.
The electroless plating is first treated with a treatment solution containing palladium chloride, a divalent copper circular salt such as cupric sulfate, a complexing agent such as ethylenediaminetetraacetic acid, a reducing agent such as formaldehyde, and a hydroxylation. An electroless plating solution composed of a pH adjusting agent such as an alkali is used, and there is no particular limitation.

FIG. 2 shows a schematic cross-sectional view of another chip-type solid electrolytic capacitor according to the present invention.
The side surface of the anode side surface plating terminal plate 8 and the side surface of the cathode side surface terminal plate 3 are formed by etching. In particular, when the anode side plating terminal plate 8 and the cathode side terminal plate 3 use a copper-based material, it is preferable to provide a solder or tin plating layer 17 on the outer surface and side surfaces thereof. This makes it easy to form comparable solder fillets at both ends of the capacitor and prevents chip standing.

FIG. 3 shows an example of a method for manufacturing a chip-type solid electrolytic capacitor according to the present invention.
The side surface of the anode side plating terminal plate shows a method of forming by etching.
In FIG. 3A, a metal plate is arranged on the bottom surface side of a container with an open top surface, and a plurality of capacitor elements are suspended above the metal plate in accordance with a predetermined position with the anode lead side facing upward. This shows a step of solidifying the adhesive adhesive and the cathode layer and filling the container with an exterior insulating resin so that the cathode layer is buried.
FIG. 3B shows a step of providing a plating layer serving as an anode side terminal while cutting the anode lead or the lead metal in the middle.
FIG. 3C shows that an etching resist mask is provided on the surface of the plating layer, and the plating layer is divided by etching.
FIG. 3D shows a step of cutting adjacent regions of the capacitor element on the metal plate.

First, as shown to Fig.3 (a), the metal plate 11 is arrange | positioned at the inner bottom face side of the container 12 with an open top surface. The container 12 is easier to use if it can be divided into a bottom part and a side part. Moreover, it becomes easy to prevent the exterior resin from flowing out by pressing the peripheral portion of the metal plate 11 through the packing 13 on the bottom of the side surface of the container 12. Although the material of the container 12 is not particularly limited, if a silicone resin-based molded body is used for the side surface portion, the packing 13 can be omitted, and the peelability from the exterior resin becomes good.
Next, the capacitor element 1 is an anode sintered body formed by embedding one end of an anode lead for valve action metal, press-pressing and sintering a powder obtained by mixing a binder with fine powder of valve action metal, and sintering. Comb tip of lead metal 5 formed in a comb shape in accordance with a predetermined position with a general capacitor element in which an anodic oxide film, a solid electrolyte layer, and a cathode layer of a carbon layer or a silver layer are sequentially provided on the body On the side, the tip end side of the anode lead 2 is welded, arranged in a row with a gap, and suspended. A plurality of rows are provided depending on production efficiency. A conductive adhesive 4 is provided on the surface opposite to the surface of the anode lead 2. When the lead metal 5 is not used, the tip end side of the anode lead 2 of the capacitor element 1 is welded to a plate-shaped stainless steel plate, arranged in a line with a gap, and suspended. The capacitor element 1 is lowered, the conductive adhesive 4 and the metal plate 11 are connected, and after solidification, the container is filled with an insulating resin that becomes the exterior resin 7 so that the cathode layer 14 is buried.

  Next, as shown in FIG. 3B, after the surface of the insulating resin is surface-treated, an electroless plating layer 9 of, for example, copper of about 5 to 50 μm is provided as a base. After cutting the lead metal 5 (the anode lead 2 when the lead metal 5 is not used), for example, a copper electrolytic plating layer 10 having a thickness of about 50 μm to 500 μm is provided. In addition, a plating layer of nickel, zinc, tin, or the like is appropriately provided on the upper layer. The electroless plating may be performed after cutting the lead metal 5 (or the anode lead 2 when the lead metal 5 is not used). The electroless plating or electrolytic plating may be performed after removing the side plate of the container.

Next, as shown in FIG. 3C, an etching resist mask 15 is provided on the surface of the plating layer, and the plating layer is divided by etching. A groove may be provided on the surface of the plating layer. As the etching resist, a liquid resist and a film resist can be used.

Next, as shown in FIG. 3D, after removing the mask 15 of the etching resist, a double-sided adhesive 16 of a type whose adhesiveness is weakened by heating between the inner bottom surface of the container 12 and the metal plate 11. And adjacent regions of the capacitor element 1 on the metal plate 11 are cut with a diamond cutter or the like. After heating, the individual capacitors are removed. Although the double-sided adhesive 16 is provided between the container 12 and the metal plate 11 in the figure, a flat plate may be used instead of the container 12. The etching resist mask 15 may be removed after cutting. Moreover, in FIG. 3, although it cut | disconnected from the plating layer surface, you may turn over and cut | disconnect from the direction of the metal plate 11. FIG.

FIG. 4 shows an example of a method for manufacturing another chip-type solid electrolytic capacitor according to the present invention.
The side surface of the anode side plating terminal plate and the side surface of the cathode side surface terminal plate show a method of forming by etching.
3 (c) is different from FIG. 3 (c). In FIG. 4 (c), the product is removed from the container 12, and an etching resist mask 15 is provided on the surface of the plating layer and the back surface of the metal plate. It also shows that the metal plate has been divided. A groove may be provided on the surface of the plating layer and the metal plate. Next, a solder tin or tin plating layer can be appropriately provided on the surface and side surfaces of the plating layer and the metal plate. When it is divided, it can be formed by electroless plating, and when it is cut, it can be formed by electrolytic plating.

1 shows a schematic view of a chip-type solid electrolytic capacitor according to the present invention. The schematic of another chip type solid electrolytic capacitor concerning the present invention is shown. 1 illustrates a method for manufacturing a chip-type solid electrolytic capacitor according to the present invention. 3 shows another method for manufacturing a chip-type solid electrolytic capacitor according to the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Capacitor element, 2 ... Lead for anode, 3 ... Cathode side terminal board, 4 ... Conductive adhesive, 5 ... Lead-out metal, 6 ... Through-hole, 7 ... Exterior resin, 8 ... Anode side plating terminal board, 9 ... Electroless plating layer, 10 ... Electrolytic plating layer, 11 ... Metal plate, 12 ... Container, 13 ... Packing, 14 ... Cathode layer, 15 ... Mask for etching resist, 16 ... Double-sided adhesive, 17 ... Solder or tin plating layer.

Claims (4)

  An anode sintered body formed by embedding one end of a valve action metal anode lead, press-pressing and sintering a powder obtained by mixing a binder with a fine powder of the valve action metal, and sintering the sintered body. A capacitor element in which an anodic oxide film, a solid electrolyte layer, and a cathode layer are sequentially provided, an anode side-plated terminal plate connected to the anode lead directly or via a lead metal, and conductive to the side of the cathode layer In the solid electrolytic capacitor having a cathode side surface terminal plate connected by a conductive adhesive and an exterior resin that encloses the capacitor element and separates the anode side surface plated terminal plate and the cathode side surface terminal plate, the anode side surface plating A chip-type solid electrolytic capacitor, wherein a side surface of a terminal plate is formed by etching.   2. The chip-type solid electrolytic capacitor according to claim 1, wherein a side surface of the anode side surface plating terminal plate and a side surface of the cathode side surface terminal plate are formed by etching. Placing the metal plate on the bottom side of the open container;
An anode sintered body formed by embedding one end of a valve action metal anode lead above the metal plate, press-pressing and sintering a powder obtained by mixing a binder with a fine powder of the valve action metal. And a step of hanging a plurality of capacitor elements in which the sintered body is sequentially provided with an anodic oxide film, a solid electrolyte layer, and a cathode layer with the anode lead side facing upward,
A step of connecting and solidifying the metal plate and the cathode layer with a conductive adhesive provided on the surface of the cathode layer opposite to the anode lead side or at a predetermined position of the metal plate;
Filling the container with an exterior insulating resin so that the cathode layer is buried;
A step of providing a plating layer for an anode side plating terminal plate electrically connected to the anode lead side on the surface of the exterior insulating resin while cutting the anode lead side in the middle;
Etching a region adjacent to the capacitor element of the plating layer;
And a step of cutting adjacent regions of the capacitor element on the metal plate. Placing the metal plate on the bottom side of the open container;
An anode sintered body formed by embedding one end of a valve action metal anode lead above the metal plate, press-pressing and sintering a powder obtained by mixing a binder with a fine powder of the valve action metal. And a step of hanging a plurality of capacitor elements in which the sintered body is sequentially provided with an anodic oxide film, a solid electrolyte layer, and a cathode layer with the anode lead side facing upward,
A step of connecting and solidifying the metal plate and the cathode layer with a conductive adhesive provided on the surface of the cathode layer opposite to the anode lead side or at a predetermined position of the metal plate;
Filling the container with an exterior insulating resin so that the cathode layer is buried;
A step of providing a plating layer for an anode side plating terminal plate electrically connected to the anode lead side on the surface of the exterior insulating resin while cutting the anode lead side in the middle;
Removing from the container, providing an etching resist mask on both sides, and etching the adjacent region of the capacitor element of the plating layer;
And a step of cutting adjacent regions of the capacitor element on the metal plate.

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