JP2006140443A - Solid electrolytic capacitor and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid electrolytic capacitor which has large capacitance and low ESR with high reliability, and a method of manufacturing the same. <P>SOLUTION: The solid electrolytic capacitor uses a conductive high polymer as a solid electrolyte, and includes an anode body 1, a dielectric oxide film 2 formed on a surface of the anode body 1, a first conductive high polymer layer 3 partially formed on the dielectric oxide film 2, a silanol coupling agent treatment layer 4 formed on the dielectric oxide film 2 where at least the first conductive high polymer layer 3 is not formed, and a second conductive high polymer layer 5 formed on the first conductive high polymer layer 3 and the silanol coupling agent treatment layer 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a solid electrolytic capacitor using a conductive polymer compound as a solid electrolyte and a method for manufacturing the same.

  In recent years, along with the downsizing and weight reduction of electronic devices, there has been a demand for small, high-capacity high-frequency capacitors, and as such capacitors, solids in which a solid electrolyte layer is formed using a conductive polymer compound. Electrolytic capacitors have been proposed.

  In the above solid electrolytic capacitor, a dielectric oxide film formed by oxidizing the surface of an anode body made of a sintered body of a valve metal such as tantalum, niobium, titanium or aluminum, and a dielectric oxide film on the dielectric oxide film There are problems such as an increase in LC (Leaked Current) due to a decrease in adhesion between the formed solid electrolyte layer and a decrease in reliability due to an increase in ESR (Equivalent Series Resistance).

  In order to solve such problems, a dielectric oxide film is formed on the surface of the anode body, and further, the surface is treated with a silane coupling agent, and then a conductive polymer compound layer is formed on the surface as a solid electrolyte layer. Proposed to improve the adhesion between the dielectric oxide film and the conductive polymer compound layer by interposing a silane coupling agent between the dielectric oxide film and the conductive polymer compound layer. (For example, see Patent Document 1 to Patent Document 3).

  Furthermore, for the anode body which is a porous body, in order to improve the adhesion between the dielectric oxide film formed on the anode body surface and the conductive polymer compound, silane coupling to the dielectric oxide film is performed. The first surface treatment layer of the silane coupling agent is formed on the dielectric oxide film inside the porous body by repeating the treatment with the agent and the formation of the conductive polymer compound layer, and the first surface treatment layer is formed on the first surface treatment layer. A first conductive polymer compound layer is formed, a second surface treatment layer of a silane coupling agent is formed on the dielectric oxide film on the outer periphery of the porous body, and a second surface treatment layer is formed on the second surface treatment layer. It has been proposed to improve the adhesion between the dielectric oxide film and the conductive polymer compound layer by forming the second conductive polymer compound layer (see, for example, Patent Document 4).

However, depending on the above method, although the adhesion between the dielectric oxide film and the conductive polymer compound layer is improved and the ESR is kept low and the reliability is improved, the dielectric oxide film and the conductive polymer are improved. There was a problem that the electrostatic capacity was lowered due to the presence of a surface treatment layer (silane coupling agent treatment layer, hereinafter the same) of a silane coupling agent formed between the compound layer.
Japanese Patent Application Laid-Open No. 02-074021 Japanese Patent Laid-Open No. 04-073924 Japanese Patent Laid-Open No. 08-293436 Japanese Patent Laid-Open No. 11-2119880

  An object of the present invention is to provide a solid electrolytic capacitor having a large capacitance, low ESR and high reliability, and a method for manufacturing the same.

  The present invention relates to a solid electrolytic capacitor using a conductive polymer compound as a solid electrolyte, an anode body, a dielectric oxide film formed on the surface of the anode body, and a part formed on the dielectric oxide film The first conductive polymer compound layer formed, the silane coupling agent-treated layer formed on the dielectric oxide film on which at least the first conductive polymer compound layer is not formed, and the first conductivity A solid electrolytic capacitor including a second conductive polymer compound layer formed on the polymer compound layer and the silane coupling agent treatment layer.

  In the solid electrolytic capacitor according to the present invention, a distance between one partial layer constituting the first conductive polymer compound layer and a partial layer adjacent to the partial layer can be set to 10 nm or more and less than 100 μm. In addition, the first conductive polymer compound layer and the second conductive polymer compound layer can contain polypyrrole or polythiophene.

  The present invention relates to a method for producing a solid electrolytic capacitor using a conductive polymer compound as a solid electrolyte, comprising a step of forming a dielectric oxide film on the surface of an anode body, and a part of the method on the dielectric oxide film. A step of forming one conductive polymer compound layer, a step of forming a silane coupling agent-treated layer on a dielectric oxide film on which at least the first conductive polymer compound layer is not formed, Forming a second conductive polymer compound layer on the conductive polymer compound layer and the silane coupling agent-treated layer.

  In the method for producing a solid electrolytic capacitor according to the present invention, the distance between one partial layer constituting the first conductive polymer compound layer and a partial layer adjacent to the partial layer can be set to 10 nm or more and less than 100 μm. . The first conductive polymer compound layer can be formed by chemical oxidative polymerization or electrolytic oxidative polymerization. The second conductive polymer compound layer can be formed by chemical oxidative polymerization or electrolytic oxidative polymerization.

  As described above, according to the present invention, it is possible to provide a solid electrolytic capacitor having a large capacitance, low ESR, and high reliability, and a method for manufacturing the same.

  Referring to FIG. 1, one solid electrolytic capacitor according to the present invention is partially formed on anode body 1, dielectric oxide film 2 formed on the surface of anode body 1, and dielectric oxide film 2. The first conductive polymer compound layer 3 formed, the silane coupling agent-treated layer 4 formed on the dielectric oxide film 2 on which at least the first conductive polymer compound layer 3 is not formed, And a second conductive polymer compound layer 5 formed on the one conductive polymer compound layer 3 and the silane coupling agent-treated layer 4.

  Here, since the silane coupling agent-treated layer 4 has a function as a dielectric, the present solid electrolytic capacitor has the first conductive polymer compound layer 3 and the silane coupling agent-treated layer on the dielectric oxide film 2. 4 are partially formed, and the second conductive polymer compound layer 5 is formed on the first conductive polymer compound layer 3 and the silane coupling agent-treated layer 4, whereby dielectric oxidation is performed. A dielectric layer 6 composed of the coating 2 and the silane coupling agent treatment layer 4; a solid electrolyte layer 7 composed of the first conductive polymer compound layer 3 and the second conductive polymer compound layer 5; The contact area increases, and the capacitance increases. Further, the first conductive polymer compound layer 3 and the second conductive polymer compound layer 5 (that is, the solid electrolytic layer 7) are made of a dielectric oxide film by the partially formed silane coupling agent treatment layer 4. Since it adheres to 2, low ESR can be maintained.

  On the other hand, referring to FIG. 2, one conventional solid electrolytic capacitor is formed on anode body 1, dielectric oxide film 2 formed on the surface of anode body 1, and dielectric oxide film 2. The silane coupling agent-treated layer 4, the first conductive polymer compound layer 3 formed on the silane coupling agent-treated layer 4, and the first conductive polymer compound layer 3 formed on the first conductive polymer compound layer 3. 2 conductive polymer compound layers 5. In such a conventional solid electrolytic capacitor, the adhesion between the dielectric oxide film 2 and the first conductive polymer compound layer 3 is improved by the presence of the silane coupling agent treatment layer 4 (that is, the dielectric oxide film 2 and Adhesion with the solid electrolyte layer 7 is improved). However, since the silane coupling agent treatment layer 4 has a function as a dielectric, when the silane coupling agent treatment layer 4 is formed on the dielectric oxide film 2, the dielectric layer 6 becomes thicker by that amount. As the ESR increased, the capacitance decreased.

  In one solid electrolytic capacitor according to the present invention, as described above, referring to FIG. 1, the first conductive polymer compound layer 3 and the silane coupling agent treatment layer 4 are formed on the dielectric oxide film 2. By forming each partially, dielectric layer 6 (dielectric oxide film 2 and silane coupling agent treated layer 4) and solid electrolyte layer 7 (first conductive polymer compound layer 3 and second conductive property) The contact area with the polymer compound layer 5) can be increased, the ESR can be kept low to increase the reliability as a capacitor, and the capacitance can be increased.

  In this solid electrolytic capacitor, the interval between one partial layer 3a constituting the first conductive polymer compound layer 3 and the partial layer 3b adjacent to the partial layer 3a may be 10 nm or more and less than 100 μm. preferable. When the interval between the partial layers 3a and 3b is less than 10 nm, the silane coupling agent is difficult to enter the interval between the partial layers 3a and 3b, and the formation of the silane coupling agent-treated layer 4 is inhibited. When the distance between the partial layers 3a and 3b is 100 μm or more, the dielectric layer 6 constituted by the dielectric oxide film 2 and the silane coupling material treatment layer 4 and the first conductive polymer compound layer 3 are formed. In addition, the increase in the contact area with the second conductive polymer compound layer 5 is reduced, the increase in capacitance is reduced, and a sufficient ESR reduction effect cannot be obtained. In addition, the space | interval between the partial layers 3a and 3b can be measured by SEM (scanning electron microscope) or a porosimeter (pore distribution measuring device). Here, the one partial layer constituting the first conductive polymer compound layer and the partial layer adjacent thereto may be separated or may be partially connected. The interval between the one partial layer and the adjacent partial layer refers to the shortest distance between the end of one partial layer and the end of the adjacent partial layer.

  In the present solid electrolytic capacitor, the conductive polymer compound forming the first conductive polymer compound layer and the second conductive polymer compound layer is not particularly limited, but has high conductivity and dielectric oxidation. Because it is easy to repair defects in the film 2 (insulating part of the solid electrolyte layer formed of the conductive polymer compound by detaching the dopant from the conductive polymer compound by aging or the like) , Polypyrrole or polythiophene.

  Here, the solid electrolytic capacitor will be described in detail. Referring to FIG. 1, this solid electrolytic capacitor includes a dielectric oxide film 2 obtained by oxidizing the surface of anode body 1 on the surface of anode body 1 made of a sintered body of a valve metal such as tantalum, niobium, titanium or aluminum. Is formed on the dielectric oxide film 2, the first conductive polymer compound layer 3 is partially formed on the dielectric oxide film 2, and the first conductive polymer compound layer 3 is not formed on the dielectric oxide film 2. A silane coupling agent treatment layer is formed, and a second conductive polymer compound layer 5 is formed on the first conductive polymer compound layer 3 and the silane coupling agent treatment layer 4. Here, the first conductive polymer compound layer 3 and the second conductive polymer compound layer 5 constitute a solid electrolyte layer 7. Furthermore, a carbon layer 8 containing conductive carbon is formed on the second conductive polymer compound layer 5, and a cathode lead layer 9 made of silver paste or the like is formed on the carbon layer 8 to constitute the capacitor element 10. Has been. Further, an anode terminal 21 is connected to the anode lead member 11 planted on one end face of the anode body 1, a cathode terminal 22 is connected to the cathode lead layer 9, and the capacitor element 10 is an exterior resin such as an epoxy resin. 12 is hermetically sealed.

  A method for manufacturing a solid electrolytic capacitor according to the present invention includes a step of forming a dielectric oxide film 2 on the surface of an anode body 1 with reference to FIG. Forming the conductive polymer compound layer 3, forming the silane coupling agent treatment layer 4 on the dielectric oxide film 2 on which at least the first conductive polymer compound layer 3 is not formed, Forming a second conductive polymer compound layer 5 on the first conductive polymer compound layer 3 and the silane coupling agent treatment layer 4.

  A first conductive polymer compound layer 3 and a silane coupling agent treatment layer 4 are partially formed on the dielectric oxide film 2, respectively, and the conductive polymer compound layer 3 and the silane coupling agent treatment layer 4 are formed. The second conductive polymer compound layer 5 is formed on the dielectric layer 6 (dielectric oxide film 2 and silane coupling agent treated layer 4) and the solid electrolyte layer 7 (first conductive polymer compound). Since the contact area between the layer 3 and the second conductive polymer compound layer) increases, the capacitance increases.

  Here, the manufacturing method of this solid electrolytic capacitor is demonstrated in detail. The step of forming the dielectric oxide film 2 on the surface of the anode body 1 includes oxidizing the surface of the anode body 1 made of a sintered body of a valve metal such as tantalum, niobium, titanium, or aluminum to form a dielectric layer. Form. The method of forming the dielectric oxide film 2 is not particularly limited, but for example, a method of anodizing the anode body 1 in a phosphoric acid aqueous solution is preferably used.

  A method for partially forming the first conductive polymer compound layer 3 on the dielectric oxide film 2 is not particularly limited, but a chemical oxidative polymerization method or an electrolytic oxidative polymerization method is preferably used. Here, the chemical oxidative polymerization method is a method in which a monomer is oxidatively polymerized using an oxidant, and is an excellent method in that a conductive polymer compound layer can be formed within the small pores of the anode body. The oxidizing agent is not particularly limited, but persulfates such as ammonium persulfate, potassium persulfate and sodium persulfate, metal halides such as ferric chloride and aluminum chloride, peroxides such as hydrogen peroxide, etc. Used. Electrolytic oxidation polymerization is a method in which a monomer is oxidatively polymerized on the anode using an oxidation reaction occurring at the anode, and is an excellent method in that the thickness and physical properties of the conductive polymer compound layer can be easily controlled. In chemical oxidation polymerization or electrolytic oxidation polymerization, the first conductive polymer compound is partially formed on the dielectric oxide film 2 by adjusting the polymerization conditions such as the monomer concentration of the polymerization solution, the temperature of the polymerization solution, and the polymerization time. Layer 3 can be formed. Further, in the formation of the conductive polymer compound layer, a dopant is added during monomer polymerization in order to develop and improve conductivity. The dopant is not particularly limited as long as it is easily incorporated into the conductive polymer and enhances its conductivity, but sulfonic acid such as benzenesulfonic acid, alkylbenzenesulfonic acid, naphthalenesulfonic acid, alkylnaphthalenesulfonic acid or the like. A salt is preferably used from the viewpoint of high conductivity.

  In the step of forming the first conductive polymer compound layer 3, the distance between one partial layer 3a constituting the first conductive polymer compound layer and the partial layer 3b adjacent to the partial layer 3a is 10 nm or more. It is preferable to be less than 100 μm. When the interval between the partial layers 3a and 3b is less than 10 nm, the silane coupling agent is difficult to enter the interval between the partial layers 3a and 3b, and the formation of the silane coupling agent-treated layer 4 is inhibited. When the distance between the partial layers 3a and 3b is 100 μm or more, the dielectric layer 6 constituted by the dielectric oxide film 2 and the silane coupling material treatment layer 4 and the first conductive polymer compound layer 3 are formed. In addition, the increase in the contact area with the second conductive polymer compound layer 5 is reduced, the increase in capacitance is reduced, and a sufficient ESR reduction effect cannot be obtained. Here, the interval between the partial layers 3a and 3b can be controlled by adjusting the polymerization conditions such as the concentration and temperature of the polymerization solution and the polymerization time in chemical oxidation polymerization or electrolytic oxidation polymerization. For example, the lower the monomer concentration in the polymerization solution, the lower the temperature of the polymerization solution, and the shorter the polymerization time, the greater the distance between the partial layers 3a and 3b.

  There is no particular limitation on the method of forming the silane coupling agent treatment layer 4 on the dielectric oxide film 2 on which at least the first conductive polymer compound layer 3 is not formed, but from the viewpoint of excellent workability, Method of dipping anode body 1 after the step of forming first conductive polymer compound layer 3 partially on dielectric oxide film 2 in a solution containing a silane coupling agent and then drying, or dielectric oxidation A method of drying after applying a solution containing a silane coupling agent on the dielectric oxide film 2 of the anode body 1 after the step of partially forming the first conductive polymer compound layer 3 on the film 2 A method of surface-treating the dielectric oxide film 2 using a silane coupling agent is preferably used. By the above method, the silane coupling agent-treated layer 4 is mainly formed on the dielectric oxide film 2 on which the first conductive polymer compound layer 3 is not formed. Although a silane coupling agent treatment layer may be formed on the first conductive polymer compound layer 3 as well, it does not deteriorate the characteristics as a solid electrolytic capacitor.

  The silane coupling agent used for forming the silane coupling agent treated layer 4 is not particularly limited as long as it has dielectric properties and improves the adhesion between the dielectric oxide film 2 and the solid electrolyte layer 7. Chlorosilane (also expressed as vinyltrichlorosilane), vinyl (β-methoxysilane), vinyltriethoxysilane, γ-methacryloxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxy Propyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl -Γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysila And γ-chloropropyltrimethoxysilane.

  The method for forming the second conductive polymer compound layer 5 on the first conductive polymer compound layer 3 and the silane coupling agent-treated layer 4 is not particularly limited. An oxidative polymerization method is preferably used. As described above, the chemical oxidative polymerization method is an excellent method in that the conductive polymer compound layer can be formed within the small pores of the anode body, and the electrolytic oxidative polymerization is the thickness and physical properties of the conductive polymer compound layer. This method is excellent in that it is easy to control. Further, unlike the first conductive polymer compound layer 3, the second conductive polymer compound layer 5 covers the entire surface of the first conductive polymer compound layer 3 and the silane coupling agent treatment layer 4. It is preferable. From this point of view, the formation of the second conductive polymer compound has a higher monomer concentration of the polymerization solution, a higher temperature of the polymerization solution, and a polymerization time compared to the formation of the first conductive polymer compound layer. Is preferably carried out under long polymerization conditions.

Example 1
Referring to FIG. 1, 2.3 mm × 1.8 mm × 1.0 mm formed of a tantalum (Ta) sintered body in which anode lead member 11 is planted on one end surface (2.3 mm × 1.0 mm). A dielectric oxide film 2 was formed by subjecting the rectangular parallelepiped anode body 1 to electrolytic oxidation for 10 hours by applying a constant voltage of 10 V in a phosphoric acid aqueous solution at 65 ° C.

  Next, this element was immersed in an ethanol solution containing pyrrole 3.0M (mol / liter concentration, the same applies hereinafter) at 25 ° C. for 5 minutes, and then ammonium persulfate 0.1M and alkylnaphthalenesulfonic acid 0.1M were added. The first conductive polymer compound layer 3 was partially formed on the dielectric oxide film 2 by dipping in the aqueous solution containing the solution for 5 minutes. When the distance between the partial layers 3a and 3b of the first conductive polymer compound layer 3 was measured by SEM, it was 10 nm or more and less than 100 μm.

  Next, the device was immersed in an aqueous solution at 25 ° C. containing 3.0% by mass of γ-glycidoxypropyltrimethoxysilane (silane coupling agent “KBM-403” manufactured by Shin-Etsu Chemical Co., Ltd.) for 5 minutes, and then 130 ° C. Was dried for 20 minutes to form a silane coupling agent treated layer 4 on the dielectric oxide film 2 on which at least the first conductive polymer compound layer 3 was not formed. Next, using this element as an anode, a current of 0.5 mA was passed for 3 hours in an aqueous solution at 25 ° C. containing 0.2 M of pyrrole and 0.2 M of alkylnaphthalenesulfonic acid, whereby the second conductive polymer compound. Layer 5 was formed.

  Next, a carbon layer 8 containing conductive carbon and a cathode lead layer 9 were sequentially formed on the second conductive polymer compound layer 5 to obtain a capacitor element 10. Further, the anode terminal 21 is welded to the anode lead member 11 and the cathode terminal 22 is connected to the cathode lead layer 9 with a conductive adhesive, and then the outside of the capacitor element 10 is covered and sealed with an exterior resin 12 formed of an epoxy resin. Then, an aging treatment was performed to produce a solid electrolytic capacitor.

  For the solid electrolytic capacitor obtained as described above, initial ESR, ESR after applying a constant voltage of 2.5 V at 105 ° C. for 500 hours, and applying a constant voltage of 2.5 V at 105 ° C. for 1000 hours The ESR was measured and found to be 20.8 mΩ, 24.0 mΩ and 26.0 mΩ, respectively. Here, the ESR was measured using an LCR meter (inductance-capacitance-resistance measuring apparatus). Table 1 summarizes the results of ESR of the solid electrolytic capacitor at the initial stage and after the voltage application test at a high temperature.

  Further, regarding the obtained solid electrolytic capacitor, the initial capacitance appearance rate was calculated to be 86.3%. Here, the capacitance appearance rate is the percentage of the actual capacitance of the produced solid electrolytic capacitor with respect to the capacitance obtained by measuring the element after forming the dielectric oxide film in a 30% by mass sulfuric acid aqueous solution ( %). The actual capacitance was measured using an LCR meter.

  Furthermore, when the initial LC of the obtained solid electrolytic capacitor was measured, it was 1.97 μA. Here, the LC is measured and calculated by connecting a 1 kΩ resistor in series to the capacitor to be measured, connecting a voltmeter in parallel to the resistor, and dividing the measured voltage by the resistance value to calculate the LC. It was done by asking. Table 2 summarizes the results of ESR, capacitance appearance rate, and LC of the solid electrolytic capacitor in the initial stage.

(Comparative Example 1)
A solid electrolytic capacitor was produced in the same manner as in Example 1 except that the device was not immersed in an aqueous solution of 3.0% by mass of γ-glycidoxypropyltrimethoxysilane and the silane coupling agent treatment layer was not formed. . The initial ESR of the obtained solid electrolytic capacitor, ESR after application of 105 ° C. × constant voltage 2.5V × 500 hours, and ESR after application of 105 ° C. × 2.5 V × 1000 hours are 21.5 mΩ and 35.0 mΩ, respectively. And 54.0 mΩ. Table 1 summarizes the results of ESR of the solid electrolytic capacitor at the initial stage and after the voltage application test at a high temperature. The initial capacitance appearance rate of the obtained solid electrolytic capacitor was 82.1%, and the initial LC was 9.45 μA. Table 2 summarizes the results of ESR, capacitance appearance rate, and LC of the solid electrolytic capacitor in the initial stage.

  As is apparent from Table 1, the solid electrolytic capacitor according to the present invention in which the silane coupling agent-treated layer is formed after the formation of the first conductive polymer compound layer can be subjected to ESR even when voltage is continuously applied at a high temperature. In the conventional solid electrolytic capacitor in which the silane coupling agent treatment layer was not formed, the ESR was remarkably increased by applying a voltage continuously at a high temperature. It is considered that the adhesion between the dielectric oxide film of the conventional solid electrolytic capacitor and the solid electrolyte layer is lowered due to the voltage marking.

(Comparative Example 2)
Referring to FIG. 2, the element on which dielectric oxide film 2 is formed is immersed in an aqueous solution at 25 ° C. containing 3.0% by mass of γ-glycidoxypropyltrimethoxysilane for 5 minutes and then dried at 130 ° C. for 20 minutes. After forming the silane coupling agent-treated layer 4 on the dielectric oxide film 2, this element was immersed in an ethanol solution containing 3.0M pyrrole at 25 ° C. for 5 minutes, and then 0.1M ammonium persulfate. The first conductive polymer compound layer 3 was formed on the silane coupling agent-treated layer 4 by immersing in an aqueous solution containing 0.1M of alkylnaphthalenesulfonic acid for 5 minutes. Next, using this element as an anode, The first conductive polymer compound layer 3 was obtained by applying a current of 0.5 mA for 3 hours in a 25 ° C. aqueous solution containing 0.2 M of pyrrole and 0.2 M of alkylnaphthalenesulfonic acid. The except for forming a second conductive polymer compound layer 5, in the same manner as in Example 1 to prepare a solid electrolytic capacitor. The initial ESR, capacitance appearance rate, and LC of the obtained solid electrolytic capacitor were 21.0 mΩ, 79.3%, and 6.88 μA, respectively. The results are summarized in Table 2.

  As is apparent from Table 2, the solid electrolytic capacitor of Example 1 in which the silane coupling agent-treated layer was formed after the first conductive polymer compound layer was formed was between the dielectric oxide film and the solid electrolyte layer. Compared with the solid electrolytic capacitor of Comparative Example 1 in which the silane coupling agent-treated layer was not formed, the capacitance expression rate increased and ESR and LC decreased. In the solid electrolytic capacitor of Example 1, the silane coupling agent-treated layer and the solid electrolyte layer are partially formed on the dielectric oxide film, so that the dielectric oxide film and the silane coupling agent-treated layer are used. Since the contact area between the dielectric layer constituted and the solid electrolyte layer constituted by the first conductive polymer compound layer and the second conductive polymer compound layer is increased, the dielectric oxide film and the solid This is thought to be due to improved adhesion to the electrolyte layer.

  Further, the solid electrolytic capacitor of Example 1 has an increased capacitance development rate as compared with the solid electrolytic capacitor of Comparative Example 2 in which the first conductive polymer compound layer is formed after the silane coupling agent treatment layer is formed. ESR and LC were reduced. As is clear from a comparison between FIG. 1 and FIG. 2, the dielectric layer 6 formed by the dielectric oxide film 2 and the silane coupling agent treatment layer 4, the first conductive polymer compound layer 3, and the first The contact area with the solid electrolyte layer 7 formed by the conductive polymer compound layer 5 of 2 is considered that the solid electrolytic capacitor of Example 1 was larger than the solid electrolytic capacitor of Comparative Example 2.

  Moreover, although the solid electrolytic capacitor of the comparative example 2 reduced LC compared with the solid electrolytic capacitor of the comparative example 1, it also reduced the capacitance appearance rate. This is probably because the dielectric layer composed of the dielectric oxide film and the silane coupling agent treatment layer is thickened by forming the silane coupling agent treatment layer entirely on the dielectric oxide film. . On the other hand, in the solid electrolytic capacitor of Example 1, since the silane coupling agent-treated layer is only partially formed on the dielectric oxide film, it is composed of the dielectric oxide film and the silane coupling agent-treated layer. Since the dielectric layer does not become thicker, it is considered that the dopant is easily detached from the conductive polymer compound forming the solid electrolyte layer during the aging treatment, and further LC reduction effect is obtained.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a cross-sectional schematic diagram which shows one solid electrolytic capacitor concerning this invention. It is a cross-sectional schematic diagram which shows one conventional solid electrolytic capacitor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode body, 2 Dielectric oxide film, 3 1st electroconductive polymer compound layer, 3a, 3b partial layer, 4 Silane coupling agent processing layer, 5 2nd electroconductive polymer compound layer, 6 Dielectric layer 7 solid electrolyte layer, 8 carbon layer, 9 cathode lead layer, 10 capacitor element, 11
Anode lead member, 12 exterior resin, 21 anode terminal, 22 cathode terminal.

Claims (7)

A solid electrolytic capacitor using a conductive polymer compound as a solid electrolyte,
An anode body, a dielectric oxide film formed on the surface of the anode body, a first conductive polymer compound layer partially formed on the dielectric oxide film, and at least a first conductive high A silane coupling agent-treated layer formed on a dielectric oxide film on which no molecular compound layer is formed, and a first layer formed on the first conductive polymer compound layer and the silane coupling agent-treated layer. A solid electrolytic capacitor comprising two conductive polymer compound layers.   2. The solid electrolytic capacitor according to claim 1, wherein an interval between one partial layer constituting the first conductive polymer compound layer and a partial layer adjacent to the partial layer is 10 nm or more and less than 100 μm.   The solid electrolytic capacitor according to claim 1 or 2, wherein the first conductive polymer compound layer and the second conductive polymer compound layer contain polypyrrole or polythiophene. A method for producing a solid electrolytic capacitor using a conductive polymer compound as a solid electrolyte,
A step of forming a dielectric oxide film on the surface of the anode body; a step of partially forming a first conductive polymer compound layer on the dielectric oxide film; and at least the first conductive polymer compound A step of forming a silane coupling agent-treated layer on the dielectric oxide film on which no layer is formed, and a second conductive property on the first conductive polymer compound layer and the silane coupling agent-treated layer. A method for producing a solid electrolytic capacitor comprising a step of forming a polymer compound layer.   The manufacturing method of the solid electrolytic capacitor of Claim 4 which makes the space | interval of the one partial layer which comprises the said 1st electroconductive polymer compound layer, and the partial layer adjacent to the said partial layer 10 nm or more and less than 100 micrometers.   The method for producing a solid electrolytic capacitor according to claim 4 or 5, wherein the first conductive polymer compound layer is formed by chemical oxidation polymerization or electrolytic oxidation polymerization.   6. The method for producing a solid electrolytic capacitor according to claim 4, wherein the second conductive polymer compound layer is formed by chemical oxidation polymerization or electrolytic oxidation polymerization.

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