JP5020432B2 - Chip type multilayer capacitor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a chip-type multilayer capacitor.
[0002]
[Prior art]
As a conventional multilayer capacitor, one disclosed in Japanese Patent Laid-Open No. 8-115855 is known.
[0003]
As shown in FIG. 7, the multilayer capacitor is mounted on the lead terminal 2 with the directions of the plurality of capacitor elements 1 aligned, and then the anode lead terminal 3 is in contact with the contact 4, and the anode portion is formed by the conductive material 5. It was configured to be integrated so as to fill the space.
[0004]
[Problems to be solved by the invention]
In the conventional multilayer capacitor, the conductive material 5 is filled between the anode portions, and the anode lead terminal 3 is in contact with and integrated with the contact 4, so that the resistance value of the conductive material 5 and the anode lead terminal 3 itself is high and ESL Since the (inductance component) also increases, there is a problem that the high frequency characteristics are inferior.
[0005]
The present invention solves the above-described conventional problems, and an object of the present invention is to provide a chip-type multilayer capacitor having excellent high-frequency characteristics.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has the following configuration.
[0007]
The invention according to claim 1 is formed by electrically connecting an electrical connection between the capacitor laminate and the cathode layer by an extraction electrode portion provided between the capacitor laminate and the cathode layer. (Resistance component) is reduced and ESL is also lowered, so that the high frequency response is excellent.
[0008]
Further, in the invention described in claim 2, in particular, the extraction electrode portion is made of a conductive resin layer fixed to the current collector layer of the capacitor element, and the ESR is reduced and the ESL is also lowered. It has the effect of excellent responsiveness.
[0009]
Further, the invention described in claim 3 is provided with a metal connection part between the cathode layer and the conductive resin layer, and it is said that the ESR is reduced and the ESL is lowered, so that the high frequency response is excellent. Has an effect.
[0010]
Further, the invention according to claim 4 has an effect that the high frequency response is excellent because the metal connection portion is provided with a plating layer and ESR can be reduced.
[0011]
Further, in the invention described in claim 5, in particular, the extraction electrode portion is made of a comb fixed to the side surface of the current collector layer of the capacitor element, and the cathode is directly connected in parallel from each element, so that ESR can be reduced. It has the action.
[0012]
Further, in the invention described in claim 6, in particular, the extraction electrode portion is provided with a comb on the lower surface of the capacitor laminate, and a conductive resin layer is provided so that the comb and the capacitor laminate are electrically connected. Therefore, the ESR is reduced and the ESL is lowered, so that the high frequency response is excellent.
[0013]
In the invention according to claim 7, in particular, the electrical connection between the valve action foil and the anode layer includes a cathode lead foil between the plurality of capacitor elements, and a plurality of the cathode lead foils are bundled. Thus, it is electrically connected to the cathode layer, and has the effect that the high frequency response is excellent since the ESR is reduced and the ESL is also lowered.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
Hereinafter, the chip multilayer capacitor according to Embodiment 1 of the present invention will be described with reference to the drawings.
[0015]
FIG. 1A is a cross-sectional view of a chip-type multilayer capacitor according to Embodiment 1 of the present invention, and FIG. 1B is a cross-sectional view of a capacitor element as the main part.
[0016]
As shown in the figure, the chip-type multilayer capacitor of the present embodiment is electrically connected to an exterior member 12 having a capacitor multilayer body 11 inside and a cathode of the capacitor multilayer body 11 on one side surface of the exterior member 12. A substantially U-shaped cathode layer 13 is provided with an anode layer 14 electrically connected to the anode of the capacitor laminate 11 on the other side surface.
[0017]
As shown in FIG. 2, the capacitor laminate 11 is laminated with the polarities of a plurality of capacitor elements 15. The capacitor element 15 includes a valve action foil 16 that serves as an anode from the inner surface toward the outer surface, a valve action sintered body 17, a dielectric layer 18, a solid electrolyte layer 19 that serves as a cathode, and a current collector layer 20. Composed. FIG. 2 is a cross-sectional view of a capacitor element, which is a main part of the chip-type multilayer capacitor according to Embodiment 1 of the present invention. The valve action foil 16 is a plate-like tantalum foil. The valve action sintered body 17 is formed by covering with a valve action metal paste such as tantalum or the like so as to be substantially rectangular in top view except for a part of the valve action foil 16 and then sintering in vacuum. To do. The dielectric layer 18 is anodized in a phosphoric acid solution so as to cover the valve action sintered body 17 and the valve action foil sandwiched between the valve action sintered bodies. It forms so that the valve action foil of the part pinched | interposed into the tie may be covered. Furthermore, an insulating member 22 that separates the positive and negative electrodes is inserted through each valve action foil 16 at the interface between the valve action foil 16 that serves as the anode of the multilayer capacitor multilayer body 11 having both polarities and the valve action sintered body 17 that moves up and down. Prepare. The solid electrolyte layer 19 is provided so as to cover the dielectric layer 18, and polypyrrole or polythiophene is made into a functional polymer by a chemical polymerization method or an electrolytic polymerization method, or impregnated with a manganese nitrate solution and thermally decomposed. By doing so, a manganese dioxide layer is formed. The current collector layer 20 is provided so as to cover the solid electrolyte layer 19 and is formed by sequentially laminating a carbon layer and a silver paint layer. The capacitor laminate 11 electrically connects the cathode foil 21 between several capacitor elements 15 with the current collector layer 20 of the capacitor element 15, and is opposite to the surface having the valve action foil 16. It is formed of a metal such as nickel so as to protrude from the side surface.
[0018]
In addition, a conductive resin layer 32 made of silver, copper, or the like is fixed as the extraction electrode portion 31 to the current collector layer of the capacitor element of the capacitor multilayer body 11 serving as the cathode.
[0019]
Epoxy resin or the like so that only the end portion of the extraction electrode portion 31 that electrically connects the capacitor laminate 11 described above to the valve action foil 16 that is the anode at one end and the solid electrolyte layer 19 that is the cathode at the other end is exposed. It seals with the exterior member 12 which consists of.
[0020]
The exterior member 12 has a substantially U-shaped anode layer 14 electrically connected to the valve action foil 16 on one side surface and a substantially U-shaped cathode layer electrically connected to the extraction electrode portion 31 on the other side surface. 13 is formed by tin plating or the like. That is, the electrical connection between the capacitor laminate 11 and the cathode layer 13 is achieved by fixing the conductive resin layer 32 made of silver, copper or the like as the extraction electrode portion 31 to the current collector layer of the capacitor element. And electrically connected.
[0021]
In this embodiment, the lead electrode portion 31 is directly electrically connected to the cathode layer 13 by the conductive resin layer 32. However, as shown in FIG. 3, the lead electrode portion 31 is interposed between the conductive resin layer 32 and the cathode layer 13. When a rivet-like metal connection portion 41 made of a material having a low specific resistance such as silver or copper is provided and electrically connected, the electrical connection is ensured, and the ESR is reduced and the ESL is lowered, so that the high frequency response is excellent. This is an effect. At this time, if a metal layer 41 is further provided with a plating layer, the bonding with the cathode layer can be ensured and the interfacial resistance can be reduced, so that the high frequency response is more excellent.
[0022]
Further, as shown in FIG. 4, when the extraction electrode part 31 is a comb 51, the cathode is directly connected in parallel from each element, so that an effect of low ESR can be achieved. At this time, as shown in FIG. 5, if a comb 61 is provided on the lower surface of the capacitor multilayer body and a conductive resin layer 32 is provided so that the comb 61 and the capacitor multilayer body 11 are electrically connected, ESR is reduced. In addition, since the ESL can be lowered, the high frequency response is more excellent.
[0023]
(Embodiment 2)
Hereinafter, a chip multilayer capacitor according to Embodiment 2 of the present invention will be described with reference to the drawings.
[0024]
The difference between the present embodiment and the first embodiment is that the capacitor multilayer body 11 and the cathode layer 13 are electrically connected by using a conductive resin layer 32 as an extraction electrode portion 31 and a capacitor element. In this embodiment, a cathode extraction foil is provided between a plurality of capacitor elements, and a plurality of cathode extraction foils are bundled. And electrically connecting to the cathode layer.
[0025]
FIG. 6 is a cross-sectional view of the chip-type multilayer capacitor in accordance with Embodiment 2 of the present invention. Here, the same components as those in FIG. 1 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
[0026]
In the drawing, reference numeral 71 denotes a cathode lead foil, which is provided between a plurality of capacitor elements 15. After bundling a plurality of the cathode lead foils 71, the exterior member 12 made of an epoxy resin or the like is used so that only the end portions of the valve action foil 16 that is an anode at one end and the cathode lead foil 71 that is a cathode at the other end are exposed. Seal.
[0027]
The exterior member 12 has a substantially U-shaped anode layer 14 electrically connected to the valve action foil 16 on one side surface, and a substantially U-shaped cathode layer electrically connected to the cathode lead foil 71 on the other side surface. 13 is formed by tin plating or the like. According to this method, since the distance of the terminal connection portion of the valve action foil can be reduced as compared with the case where all the valve action foils are bundled at one place, the ESL can be reduced and the high frequency response is excellent.
[0028]
【Effect of the invention】
As described above, the present invention can be electrically connected to the cathode layer without using a lead frame, so that it is possible to achieve low ESR and low ESL, and excellent high frequency response. .
[Brief description of the drawings]
1A is a cross-sectional view of a chip-type multilayer capacitor according to a first embodiment of the present invention. FIG. 1B is a cross-sectional view of a capacitor element that is the main part. FIG. 2 is a cross-sectional view of a capacitor element that is the main part. 3 is a cross-sectional view of a chip-type multilayer capacitor according to another embodiment of the present invention. FIG. 4 is a cross-sectional view of a chip-type multilayer capacitor according to another embodiment of the present invention. FIG. 6 is a cross-sectional view of a chip-type multilayer capacitor according to a second embodiment of the present invention. FIG. 7 is a cross-sectional view of a conventional multilayer capacitor.
DESCRIPTION OF SYMBOLS 11 Capacitor laminated body 12 Exterior member 13 Cathode layer 14 Anode layer 15 Capacitor element 16 Valve action foil 17 Valve action sintered body 18 Dielectric layer 19 Solid electrolyte layer 20 Current collector layer 21 Cathode foil 22 Insulating member 31 Lead electrode part 32 Conductive resin layer 41 Metal connection part 51, 61 Com 71 Cathode extraction foil

Claims (7)

An exterior member having a capacitor laminate formed by laminating a plurality of capacitor elements therein, a cathode layer electrically connected to the capacitor laminate on at least one side surface of the exterior member, and the cathode layer on the other at least side surface An anode layer electrically connected to the capacitor laminate, and the capacitor element is formed by sintering a valve action foil made of a valve metal and serving as an anode, and a tantalum paste covering the valve action foil. The valve action sintered body is a valve action sintered body having a substantially rectangular top view made of a valve action metal from which one end of the valve action foil is exposed, and the valve action sintered body and the valve action sintered body. A dielectric layer provided so as to cover the valve action foil sandwiched between the body, a solid electrolyte layer serving as a cathode provided so as to cover the dielectric layer, and a current collector layer covering the solid electrolyte layer, is composed of a multilayer structure, As Kiben effect foil connects said anodic layer and electrically provided on the side surface of the exterior member, the valve acting foil penetrates into the interface between the valve foil and the valve action sintered body of the capacitor laminate The capacitor laminate and the cathode layer are electrically connected by an extraction electrode portion provided between the capacitor laminate and the cathode layer. Chip type multilayer capacitor.   The chip-type multilayer capacitor according to claim 1, wherein the extraction electrode portion is a conductive resin layer fixed to the current collector layer of the capacitor element.   The chip-type multilayer capacitor according to claim 2, further comprising a metal connection portion between the cathode layer and the conductive resin layer.   The chip-type multilayer capacitor according to claim 3, wherein the metal connection portion includes a plating layer.   The chip-type multilayer capacitor according to claim 1, wherein the extraction electrode portion is a comb fixed to a side surface of the current collector layer of the capacitor element multilayer body.   2. The chip-type multilayer capacitor according to claim 1, wherein the extraction electrode portion is provided with a comb on a lower surface of the capacitor multilayer body and includes a conductive resin layer so that the comb and the capacitor multilayer body are electrically connected. An exterior member having a capacitor laminate formed by laminating a plurality of capacitor elements therein, a cathode layer electrically connected to the capacitor laminate on at least one side surface of the exterior member, and the cathode layer on the other at least side surface An anode layer electrically connected to the capacitor laminate, and the capacitor element is formed by sintering a valve action foil made of a valve metal and serving as an anode, and a tantalum paste covering the valve action foil. A valve action sintered body having a substantially rectangular top view made of a valve action metal from which one end of the valve action foil is exposed,
A dielectric layer provided so as to cover the valve action sintered body and the valve action foil sandwiched between the valve action sintered body, a solid electrolyte layer serving as a cathode provided so as to cover the dielectric layer, A valve of the capacitor laminate is configured by a multilayer structure with a current collector layer covering the solid electrolyte layer, and the valve action foil is electrically connected to the anode layer provided on a side surface of the exterior member. An insulating member that passes through the valve action foil and separates the positive and negative electrodes at the interface between the action foil and the valve action sintered body is provided, and a cathode extraction foil is provided between the plurality of capacitor elements. A chip-type multilayer capacitor in which a plurality of extraction foils are bundled and electrically connected to the cathode layer.

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