JP2003318068A - Solid electrolytic capacitor and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacitor of low equivalent series resistance and a method of manufacturing the same in a solid electrolytic capacitor where solid electrolytic capacitor elements provided with solid electrolytes on valve metal substrates each having a dielectric layer are laminated. <P>SOLUTION: The solid electrolytic capacitor is a solid electrolytic capacitor where a cut-out section is provided in at least a part of the cathode in the solid electrolytic capacitor element and a conductive body is filled in the cut-out section. The method of manufacturing the solid electrolytic capacitor is characterized in that the cut-out sections are provided at the cathodes in the solid capacitors, a plurality of the solid electrolytic capacitor elements are laminated so as to allow the elements to be overlapped on each other, the conductive body is filled in the cut-out sections, and the cathodes and an anodes are each connected with a lead frame and are formed by sealing with an external resin. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a solid electrolytic capacitor and a method for manufacturing the same. More specifically, in a solid electrolytic capacitor in which valve action metal substrates having a dielectric film are laminated, the equivalent series resistance (ESR)
And a method for manufacturing the same.

[0002]

2. Description of the Related Art Recently, electronic devices have become smaller and higher in frequency, and a solid electrolytic capacitor, which is one of electronic components used therein, is also required to be smaller. Meets the demand for miniaturization.

FIG. 1 is a perspective view showing a conventional solid electrolytic capacitor having a chip shape. A plurality of solid electrolytic capacitor elements 1 inside an exterior resin 6 are arranged in the same direction. The anode part 3 and the bottom surface of the cathode part 2 formed on the surface of the element are paired so as to face each other. The anode lead part 5 is the anode lead part and the cathode lead part is the cathode lead part. It shows a state in which it is placed on the portion 4 and joined with a conductive material, for example, a conductive adhesive, and is sealed by a separately prepared exterior resin 6 such as an epoxy resin.

For example, when the solid electrolytic capacitor has a flat plate-shaped capacitor element, a dielectric film is provided on the surface of an electrode body made of a flat plate-shaped metal having a valve action, and the solid electrolyte is formed on the dielectric film. A cathode part of a capacitor element in which a cathode conductor layer is further provided on the solid electrolyte layer, an anode part is integrally provided on the electrode body of the capacitor element, and a masking resist is used as the anode lead part. A structure in which a portion provided with a film is provided, and a plurality of capacitor elements are stacked and laminated so that the connection portions of the cathode conductor layer and the anode portion correspond to each other and are connected to the cathode lead portion and the anode lead portion. By adopting, the capacity efficiency of the capacitor capacity (capacitor capacity value in a fixed volume) is increased.

As a method of reducing the equivalent series resistance of the capacitor element, a method of making a hole in the capacitor element has been proposed (for example, refer to Patent Document 1). This method cannot effectively reduce the equivalent series resistance component between the laminated capacitor elements.

[0006]

The equivalent series resistance component of the solid electrolytic capacitor has a specific resistance component of the anode lead portion, a contact resistance component at the joint surface between the anode lead portion and the anode portion of the capacitor element, and the capacitor element has The specific resistance component, the contact resistance component at the joint surface between the cathode part and the cathode lead part of the capacitor element, and the specific resistance component of the cathode lead part are mainly involved.

In the solid electrolytic capacitor having a laminated structure, the first layer capacitor element and the cathode lead portion are electrically connected by a conductive material (conductive adhesive).
Since the first-layer capacitor element is bonded to the first-layer capacitor element using a conductive material (conductive adhesive), the cathode lead portion is connected to the first-layer capacitor element through the cathode conductor layer formed on the surface of the first-layer capacitor element. There is a problem that the electrical connection is ensured, and the resistance component of the cathode conductor layer increases the equivalent series resistance of the manufactured solid electrolytic capacitor.

When a conductive adhesive or the like is applied after the capacitor elements are laminated in order to electrically connect the laminated capacitor elements and the cathode lead portion directly, the equivalent series resistance of the solid electrolytic capacitor becomes low. A step of applying a conductive adhesive over the capacitor elements occurs, which causes problems in productivity and economy.

Further, the equivalent series resistance component of the solid electrolytic capacitor can be reduced by forming the cathode lead portion to be directly bonded to each capacitor element.
Similarly, there is a problem that a complicated processing step is required for the cathode lead portion.

[0010]

[Patent Document 1] Japanese Patent Laid-Open No. 4-119624

[0011]

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, the present invention does not significantly change the conventional method for manufacturing a solid electrolytic capacitor, but simply changes the capacitor element cathode portion. By changing the shape of, it becomes possible to directly connect all the laminated capacitor elements and the cathode lead portion by using a conductive adhesive.

When the anodic oxide film is provided on the surface of the electrode body made of a flat metal having a valve action, a cathode notch portion is provided in advance at least at one portion of the capacitor element which serves as the cathode portion. After that, a solid electrolyte layer is provided, and a capacitor element having a cathode conductor layer provided on the solid electrolyte layer is further provided. An anode terminal is integrally provided on the electrode body of this capacitor element, and an insulating resin strip ( A masked portion is provided, and a plurality of capacitor elements are stacked and laminated so that the connection portions of the cathode conductor layer and the anode terminal portion correspond to each other and connected to the cathode lead portion and the anode lead portion. By doing so, a solid electrolytic capacitor having an excellent equivalent series resistance component and a low value can be obtained.

That is, the present invention provides the following solid electrolytic capacitor and its manufacturing method. 1) One end of an anode substrate made of a valve metal having a dielectric coating layer on its surface is used as an anode portion, the rest of the anode substrate has a solid electrolyte layer on the dielectric coating layer, and a conductor layer thereon. A solid electrolytic capacitor in which the anode part and the cathode part of a plurality of solid electrolytic capacitor elements each having a cathode part formed with are laminated and connected to a lead frame, and which is sealed and molded with an exterior resin. , A solid electrolytic capacitor in which at least a part of the cathode portion of each solid electrolytic capacitor element has a cutout portion, and the cutout portion is filled with a conductive material, 2) the cutout portion of the cathode portion of the solid electrolytic capacitor element is The solid electrolytic capacitor as described in 1 above, which is at the edge of the cathode part, 3) The solid electrolytic capacitor element as described in 1 or 2 above, which has an insulating resin band in a circumferential shape at the boundary between the anode part and the cathode part. Solid electrolytic capacitor, 4) The solid electrolytic capacitor as described in any one of 1 to 3 above, in which the cutout portion of the laminated cathode portion is covered with a conductive material. 5) The valve metal is aluminum, tantalum, The solid electrolytic capacitor as described in any one of 1 to 4 above, which is one kind selected from titanium, niobium and alloys thereof, 6) The valve action metal according to 1 to 4 above, which is an aluminum conversion foil or a niobium conversion foil. 7) The solid electrolytic capacitor described in any one of 7), wherein the valve metal is a chemical conversion foil obtained by a chemical conversion treatment at a voltage of less than 30V, and the solid electrolytic capacitor described in any one of 1 to 6 above, 8) The solid electrolytic capacitor as described in any one of 1 to 7 above, in which the lead frame is a copper or copper alloy-based material, 9) The solid electrolyte is a π-electron conjugated system. 10. The solid electrolytic capacitor as described in any one of 1 to 8 above, which contains a polymer, 10) The π-electron conjugated polymer is a polymer obtained from a hetero five-membered ring compound, according to 9 above. Solid electrolytic capacitors, 11) Hetero five-membered ring compounds are pyrrole, thiophene,
The solid electrolytic capacitor as described in 10 above, which is at least one selected from furan, isothianaphthene, 1,3-dihydroisothianaphthene, and substituted derivatives thereof, 12) The 5-membered heterocyclic compound is 3,4-ethylene. 11. The solid electrolytic capacitor as described in 10 above, which is at least one selected from dioxythiophene and 1,3-dihydroisothianaphthene, 13) One of the anode substrates made of a valve metal having a dielectric film layer on the surface thereof. A cathode portion is provided by forming an anode portion on an end portion, and forming a solid electrolyte layer on the dielectric coating layer of the valve metal having a cutout portion in at least a part of the remaining portion of the anode substrate, and forming a conductor layer thereon. A solid electrolytic capacitor element having, a plurality of these elements are laminated so that the cutout portions overlap, and the cutout portions are filled with a conductive material, and the cathode portion and the anode portion are respectively formed. A method for manufacturing a solid electrolytic capacitor, which comprises connecting to a lead frame and molding with an exterior resin, 14) A solid electrolytic capacitor element in which an insulating resin band is circumferentially provided at a boundary between an anode part and a cathode part. 14. The solid electrolysis as described in 13 above, wherein a plurality of cutouts are laminated so that the cutouts are overlapped, the cutouts are filled with a conductive material, the cathode part and the anode part are respectively connected to lead frames, and sealing molding is performed with an exterior resin. Method of manufacturing capacitor, and 15) One end of an anode substrate made of a valve metal having a dielectric coating layer on the surface is used as an anode part, and a solid electrolyte layer is formed on the remainder of the anode substrate on the dielectric coating layer. A solid electrolytic capacitor element in which a plurality of solid electrolytic capacitor elements each having a cathode portion on which a conductor layer is formed are laminated and connected to a lead frame. Te, each of the solid electrolyte at least partially in the notch portion of the cathode portion of the capacitor element is there, the solid electrolytic capacitor element is electrically conductive material in the notch portion is filled.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. (Valve metal) As the valve metal used as the anode substrate of the solid electrolytic capacitor in the present invention, for example, aluminum, tantalum, titanium, niobium, zirconium and alloys using these as substrates can be used. The shape of the anode substrate may be a flat foil, a plate, a rod, or the like. Of these, aluminum chemical conversion foils are often used in practice because of their excellent economic efficiency. As this aluminum chemical conversion foil, a rectangular one having a thickness of 40 to 200 μm and a flat element unit of about 1 to 30 mm in length and width is used. Width 2 to 20 mm, length 2 to 20 m
m, more preferably 2 to 5 mm in width and 2 to 6 mm in length.

The dielectric coating layer provided on the surface of the anode substrate is
Although it may be an oxide layer of the valve action metal itself provided on the surface portion of the valve action metal, or may be another dielectric layer provided on the surface of the valve action metal foil, In particular, a layer made of an oxide of the valve metal itself is desirable.

In the present invention, an anode portion is provided in one section of an end portion of a flat plate-shaped anode substrate having a dielectric coating layer formed on the surface, and a solid electrolyte layer is further formed on the remaining dielectric coating of the anode substrate. A cathode portion provided with a conductor layer is provided, and a cutout portion is provided in at least a part of the cathode portion.

The notch is preferably formed before forming the dielectric coating layer on the anode substrate (valve action metal), but after forming the dielectric coating layer on the anode substrate or the solid electrolyte layer. It is sufficient that the dielectric film can be formed on the valve action metal surface of the notch formed by providing the notch even before forming the. As a result, when the valve metal surface of the anode substrate is covered with the dielectric film layer, there is no particular problem in providing the notch.

The size of the cutout portion is the size of the cathode portion,
It depends on the number of stacked capacitor elements and is determined by preliminary experiments. The shape of the notch may be any known shape such as a circle, an ellipse, a semicircle, a triangle, and a quadrangle. The number of notches may be plural.

Further, as the portion having the cutout portion, if it is the cathode portion of the capacitor element, for example, in the case of a plate-shaped element, it may be at the edge portion (including the corner portion at the outer peripheral portion) or the flat plate central portion, but it is easy to process. The edge is preferable in terms of the strength of the element.

When an anodic oxide film is provided on the surface of a plate-shaped metal plate having a valve action, a notch 8 as shown in FIG. To provide. The shape of the cutout portion in FIG. 2 is a quadrangle, but the shape of the cutout portion does not matter. Figure 3
The cutout portion 8a may be formed on the side surface as described above.

(Solid Electrolyte) Next, a solid electrolyte is formed on the remaining dielectric coating layer other than the anode portion, but the type of solid electrolyte layer is not particularly limited, and a conventionally known solid electrolyte is used. However, solid electrolyte capacitors that use a high conductivity conductive polymer as a solid electrolyte are equivalent to series capacitors compared to conventional wet electrolytic capacitors that use electrolytic solutions and solid electrolytic capacitors that use manganese dioxide. It is preferable because it has a low resistance component, a large capacity, a small size, and good high-frequency performance.

The conductive polymer forming the solid electrolyte used in the solid electrolytic capacitor of the present invention is not limited,
Preferably, a conductive polymer having a π-electron conjugated structure, for example, a compound having a thiophene skeleton, a compound having a polycyclic sulfide skeleton, a compound having a pyrrole skeleton, a compound having a furan skeleton, etc. is contained as a repeating unit. Conductive polymers are mentioned.

Among the monomers used as the raw material of the conductive polymer, the compound having a thiophene skeleton is
For example, 3-methylthiophene, 3-ethylthiophene, 3-propylthiophene, 3-butylthiophene,
3-pentylthiophene, 3-hexylthiophene, 3
-Heptylthiophene, 3-octylthiophene, 3-
Nonylthiophene, 3-decylthiophene, 3-fluorothiophene, 3-chlorothiophene, 3-bromothiophene, 3-cyanothiophene, 3,4-dimethylthiophene, 3,4-diethylthiophene, 3,4-butylenethiophene, 3 , 4-methylenedioxythiophene,
Examples thereof include derivatives such as 3,4-ethylenedioxythiophene. These compounds are commercially available compounds or known methods (for example, Synthetic M
et al., 1986, vol. 15, p. 169).

As the compound having a polycyclic sulfide skeleton, for example, a compound having a 1,3-dihydropolycyclic sulfide (also known as 1,3-dihydrobenzo [c] thiophene) skeleton, 1,3- A compound having a dihydronaphtho [2,3-c] thiophene skeleton can be used. Furthermore, 1,3-dihydroanthra [2,3-
Examples thereof include compounds having a c] thiophene skeleton and compounds having a 1,3-dihydronaphthaceno [2,3-c] thiophene skeleton, and known methods such as JP-A 8-31
It can be prepared by the method described in No. 56 Public Relations.

Further, for example, a compound having a 1,3-dihydronaphtho [1,2-c] thiophene skeleton, 1,3
-Dihydrophenanthra [2,3-c] thiophene derivative, compound having 1,3-dihydrotriphenyl [2,3-c] thiophene skeleton, 1,3-dihydrobenzo [a] anthraceno [7,8- c] Thiophene derivatives and the like can also be used.

Some compounds optionally contain nitrogen or N-oxide in the condensed ring, such as 1,3-dihydrothieno [3,4-b] quinoxaline and 1,3-dihydrothieno [3,4-b] quinoxaline-. 4-oxide, 1,3
-Dihydrothieno [3,4-b] quinoxaline-4,9
-Dioxide and the like can be mentioned, but the invention is not limited thereto.

Examples of the compound having a pyrrole skeleton include 3-methylpyrrole, 3-ethylpyrrole, 3-propylpyrrole, 3-butylpyrrole and 3-
Pentylpyrrole, 3-hexylpyrrole, 3-heptylpyrrole, 3-octylpyrrole, 3-nonylpyrrole, 3-decylpyrrole, 3-fluoropyrrole, 3-
Chloropyrrole, 3-bromopyrrole, 3-cyanopyrrole, 3,4-dimethylpyrrole, 3,4-diethylpyrrole, 3,4-butylenepyrrole, 3,4-methylenedioxypyrrole, 3,4-ethylenedioxy Examples thereof include derivatives such as pyrrole, but are not limited thereto. These compounds can be commercially available or can be prepared by known methods.

Examples of the compound having a furan skeleton include 3-methylfuran, 3-ethylfuran, and 3
-Propylfuran, 3-butylfuran, 3-pentylfuran, 3-hexylfuran, 3-heptylfuran, 3-
Octylfuran, 3-nonylfuran, 3-decylfuran, 3-fluorofuran, 3-chlorofuran, 3-bromofuran, 3-cyanofuran, 3,4-dimethylfuran, 3,4-diethylfuran, 3,4-butylenefuran, Examples thereof include derivatives such as 3,4-methylenedioxyfuran and 3,4-ethylenedioxyfuran, but are not limited thereto. These compounds may be commercially available products or prepared by known methods.

The method of polymerization may be electrolytic polymerization, chemical oxidative polymerization, or a combination thereof. Alternatively, a method in which a solid electrolyte that is not a conductive polymer is first formed on the dielectric film and then the conductive polymer is formed by the above-mentioned polymerization method may be used.

As an example of forming a conductive polymer, 3,4
A method of forming ethylenedioxythiophene monomer and an oxidizing agent, preferably in the form of a solution, separately, before or after or together on a dielectric film (JP-A-2-156)
No. 11, JP-A-10-32145) and the like can be used.

Generally, a compound having a doping ability (dopant) is used for the conductive polymer, but the dopant may be added to either the monomer solution or the oxidant solution,
It may be an organic sulfonic acid metal salt in which the dopant and the oxidizing agent are the same compound. As the dopant, an aryl sulfonate-based dopant is preferably used. For example, salts of benzenesulfonic acid, toluenesulfonic acid, naphthalenesulfonic acid, anthracenesulfonic acid, anthraquinonesulfonic acid and the like can be used.

(Solid Electrolytic Capacitor) Then, a known conductive paste such as carbon paste and / or silver paste is laminated on the solid electrolyte layer containing the conductive polymer to form a conductive layer. Constitutes a cathode portion (conductor layer forming portion). In addition, an insulating resin layer (a resist film for masking) may be formed around the boundary between the anode part and the cathode part so as to form an insulating resin layer in a circumferential shape (in a spiral shape).

A method of stacking a plurality of capacitor elements thus formed up to the conductor layer with their directions aligned will be described. As shown in FIG. 4, the capacitor element 11a is bonded to the cathode lead portion 21 using a conductive adhesive 23a. Although the conductive adhesive is applied to the cathode lead portion in FIG. 4, the conductive adhesive may be applied to the cathode lead portion side, the capacitor element side, or both. When the capacitor element and the cathode lead portion are joined together, as shown in FIG. 5, a part of the conductive adhesive is squeezed out into the cathode cutout portion, and the conductive adhesive portion 31 is formed around the cutout portion. Then, when the capacitor element 11b is bonded onto the capacitor element 11a by using the conductive adhesive 23b, the excess conductive adhesive protruding from the cathode notch comes into contact with the conductive adhesive portion 31, as shown in FIG. The conductive adhesive portion 41 is formed integrally. The first-layer capacitor element 11a, the second-layer capacitor element 11b, and the cathode lead portion 21 are directly electrically and mechanically connected via the conductive adhesive portion 41, and the capacitor element, the cathode lead portion, and the capacitor element are connected. The effect of reducing the electrical resistance between them is brought about, and a capacitor with reduced equivalent series resistance can be obtained.

FIG. 7 is a cross-sectional view showing a state in which laminated capacitor elements are joined with a conductive adhesive. In the figure, each capacitor element is placed so that the cutout portions 8 of the cathode portion 2 of the capacitor element 1 are aligned with each other, and then the cutout portions 8 are integrally laminated by a conductive adhesive to form a laminated capacitor element. If most of the cutout portion 8 is filled with the conductive adhesive, a part of the cutout portion 8 may have a portion not filled with the conductive adhesive.

In order to further strengthen the connection between the capacitor elements, the laminated capacitor elements are integrated by immersing only the cathode portion of each capacitor element in a bath of conductive material such as silver paste and drying and hardening. You may measure. Examples of the above-mentioned conductive material include known conductive paste such as silver paste and meltable metal such as cream solder.

The solid electrolytic capacitor element thus connected to the lead frame is sealed and molded with an exterior resin such as epoxy resin by a transfer molding machine or the like, and then the convex portion of the lead frame is placed near the capacitor element. It is cut with to make a chip-shaped solid electrolytic capacitor.

The material of the lead frame is not particularly limited as long as it is generally used, but is preferably a copper type (for example, Cu-Ni type, Cu-Ag type, Cu-Sn type, Cu
-Fe system, Cu-Ni-Ag system, Cu-Ni-Sn system,
Cu-Co-P system, Cu-Zn-Mg system, Cu-Sn-
Ni-P alloy etc.) or a material plated with a copper-based material on the surface can reduce resistance by improving the shape of the lead frame and improve chamfering workability of the lead frame. The effect is obtained.

[0038]

The present invention will be described in more detail below by showing typical examples. Note that these are merely examples for description, and the present invention is not limited to these.

Examples 1 to 5 Aluminum chemical conversion foils having notches of the shapes and sizes shown in Table 1 (manufactured by Nippon Condenser Industry Co., Ltd., foil type 110).
LJB22B, rated film withstand voltage: 4 vf (hereinafter referred to as "formation foil") is divided in half from the tip by a masking material (heat-resistant resin) width 1 on both sides and both ends.
A mm masking was formed circumferentially. Cathode part (width 3mm
(Vertical length 4 mm) and an anode part, and the cathode part, which is a partition part on the tip side of this chemical conversion foil, uses a 10 mass% ammonium adipate aqueous solution as an electrolytic solution, and the temperature is 55 ° C. and the voltage is 4
It was formed under the conditions of V, current density of 5 mA / cm ² and energization time of 10 minutes, and washed with water.

Thereafter, the cathode portion was replaced with 1 mol of a solution of 3,4-ethylenedioxythiophene in isopropyl alcohol.
After immersing in 1 / l, it is left for 2 minutes, and then an oxidizing agent (ammonium persulfate: 1.5 mol / l) and a dopant (sodium naphthalene-2-sulfonate: 0.15 mol / l)
It was immersed in the mixed aqueous solution of 1) and left at 45 ° C. for 5 minutes to carry out oxidative polymerization.

The impregnation step and the polymerization step were repeated 12 times in total to form a solid electrolyte layer containing a dopant in the fine pores of the chemical conversion foil. The formed foil on which the solid electrolyte layer containing this dopant was formed was washed with water at 50 ° C. to form a solid electrolyte layer. After forming the solid electrolyte layer, a 10 mass% ammonium adipate aqueous solution is used as an electrolytic solution,
It was chemically reformed under the conditions of a temperature of 55 ° C., a voltage of 4 V, a current density of 5 mA / cm ² , and an energization time of 10 minutes, washed with water, and then dried at 100 ° C. for 30 minutes. A carbon paste and a silver paste were sequentially coated thereon to form a cathode conductor layer.

The three capacitor elements were laminated on the cathode lead portion and the anode lead portion of the lead frame by using silver paste as a conductive adhesive in the same direction and laminated to join the cathode portions. The laminated anode part was joined by spot welding the anode lead part.

The laminated structure of this capacitor element is sealed with resin, and a voltage of 2.5 V is applied for 45 minutes in an environment of 135 ° C. to have a structure in which three capacitor elements are laminated, the rated capacity is 100 μF, and the rating is 100 μF. 50 solid electrolytic capacitors having a voltage of 2 V were obtained. Table 2 shows the results of actual measurement of the capacities and equivalent series resistances of the 50 solid electrolytic capacitors thus obtained.

Example 6 The same as Example 1 except that ferric sulfate was replaced with ammonium persulfate and dihydroisothianaphthene was replaced with 3,4-ethylenedioxythiophene. Fifty capacitor elements were produced. Evaluation of these test pieces was performed in the same manner as in Example 1. The results are shown in Table 2.

Example 7 In Example 1, pyrrole was used in place of 3,4-ethylenedioxythiophene. At this time, the pyrrole solution was impregnated and dried at 3 ° C. for 5 minutes.
The same procedure as in Example 1 was repeated except that the polymerization was conducted at 10 ° C. for 10 minutes.
0 capacitor elements were produced. Evaluation of these test pieces was performed in the same manner as in Example 1. The results are shown in Table 2.

Comparative Example 1 Fifty solid electrolytic capacitors were produced in the same manner as in Example 1 except that a chemical conversion foil having no notch portion in the cathode portion was used. The performance of the solid electrolytic capacitor is shown in Table 2. In each of the examples and comparative examples, all numerical values are average values of 50 points.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

As described above, by providing the cathode notch portion in the cathode portion of the capacitor element, the surplus conductive adhesive formed in the cathode notch portion becomes the cathode regardless of the number of laminated capacitor elements. Since the lead portion and the capacitor element are directly connected, the resistance component between the laminated capacitor element and the cathode lead portion can be reduced. By reducing the resistance component between the capacitor element and the cathode lead portion, it is possible to manufacture a solid electrolytic capacitor having a low equivalent series resistance component.

[0050]

[Brief description of drawings]

FIG. 1 is a perspective view showing a conventional laminated solid electrolytic capacitor element.

FIG. 2 is a plan view showing an example of a cutout portion of a capacitor element according to the present invention.

FIG. 3 is a plan view showing an example of a cutout portion of a capacitor element according to the present invention.

FIG. 4 is a perspective view showing a state in which the first layer capacitor element of the present invention is bonded to a cathode lead portion and an anode lead portion.

FIG. 5 is a perspective view showing a state in which the second layer capacitor element of the present invention is bonded to the cathode lead portion and the anode lead portion.

FIG. 6 is a perspective view showing a state in which a second-layer capacitor element of the present invention is joined to a cathode lead portion and an anode lead portion.

FIG. 7 is a sectional view (a) and a plan view (b) of the solid electrolytic capacitor element of the present invention.

[Explanation of symbols]

1 Capacitor element 2 Cathode part 3 Anode part 4 Cathode lead part 5 Anode lead part 6 Exterior resin 7 Masking (resist film) 8,8a Notch 11a First layer capacitor element 11b Second layer capacitor element 21 Cathode lead 22 Anode lead 23a, 23b conductive adhesive 31 Conductive adhesive part 41 Conductive adhesive part

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01G 9/14 H01G 9/04 325 9/15 9/02 331G 9/24 B C F

Claims (15)

[Claims] 1. An anode part made of a valve metal having a dielectric film layer on its surface is used as an anode part, and a solid electrolyte layer is provided on the remaining part of the anode substrate, and a solid electrolyte layer is formed on the dielectric film layer. A solid electrolytic capacitor in which the anode part and the cathode part of a plurality of solid electrolytic capacitor elements each having a cathode part in which a conductor layer is formed are laminated and connected to a lead frame, and are molded by encapsulation with an exterior resin. A solid electrolytic capacitor in which a cutout portion is provided in at least a part of the cathode portion of each solid electrolytic capacitor element, and the cutout portion is filled with a conductive material. 2. The solid electrolytic capacitor according to claim 1, wherein the notch portion of the cathode portion of the solid electrolytic capacitor element is at an edge portion of the cathode portion. 3. The solid electrolytic capacitor according to claim 1, wherein the solid electrolytic capacitor element has an insulating resin band in a circumferential shape at a boundary between the anode part and the cathode part. 4. The solid electrolytic capacitor according to claim 1, wherein the cutout portion of the laminated cathode portion is covered with a conductive material. 5. The solid electrolytic capacitor according to claim 1, wherein the valve action metal is one selected from aluminum, tantalum, titanium, niobium and alloys thereof. 6. The solid electrolytic capacitor according to claim 1, wherein the valve metal is an aluminum conversion foil or a niobium conversion foil. 7. The solid electrolytic capacitor according to claim 1, wherein the valve metal is a chemical conversion foil obtained by chemical conversion treatment at a voltage of less than 30V. 8. The solid electrolytic capacitor according to claim 1, wherein the lead frame is made of a copper or copper alloy material. 9. The solid electrolytic capacitor according to claim 1, wherein the solid electrolyte contains a π-electron conjugated polymer. 10. The solid electrolytic capacitor according to claim 9, wherein the π-electron conjugated polymer is a polymer obtained from a five-membered heterocyclic compound. 11. The solid according to claim 10, wherein the five-membered heterocyclic compound is at least one selected from pyrrole, thiophene, furan, isothianaphthene, 1,3-dihydroisothianaphthene and substituted derivatives thereof. Electrolytic capacitor. 12. The solid electrolytic capacitor according to claim 10, wherein the five-membered heterocyclic compound is at least one selected from 3,4-ethylenedioxythiophene and 1,3-dihydroisothianaphthene. 13. A valve action metal having an anode portion provided at one end of a positive electrode substrate made of a valve action metal having a dielectric coating layer on its surface, and a cutout portion at least at a part of the remaining portion of the positive electrode substrate. A solid electrolyte layer is formed on the dielectric film layer, and a conductor layer is formed on the solid electrolyte layer to form a solid electrolytic capacitor element having a cathode portion. A plurality of these elements are laminated so that the notch portions are overlapped with each other to form the notch portion. A method of manufacturing a solid electrolytic capacitor, which comprises filling a conductive material, connecting the cathode part and the anode part to a lead frame, respectively, and encapsulating with an exterior resin. 14. A plurality of solid electrolytic capacitor elements, in which insulating resin strips are circumferentially provided at the boundary between the anode part and the cathode part, are stacked so that the cutouts overlap each other, and the cutouts are filled with a conductive material. The method for producing a solid electrolytic capacitor according to claim 13, wherein the cathode part and the anode part are respectively connected to a lead frame, and encapsulation molding is performed with an exterior resin. 15. One end of an anode substrate made of a valve metal having a dielectric coating layer on its surface is used as an anode part, and the remaining part of the anode substrate is a solid electrolyte layer on which the solid electrolyte layer is formed. A solid electrolytic capacitor element in which the anode part and the cathode part of a plurality of solid electrolytic capacitor elements each having a cathode part on which a conductor layer is formed are laminated and connected to a lead frame. A solid electrolytic capacitor element in which at least a part of a cathode portion of the electrolytic capacitor element has a cutout portion, and the cutout portion is filled with a conductive material.