JPS596501B2 - Manufacturing method of solid electrolytic capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a solid electrolytic capacitor using semiconducting manganese oxide as its solid electrolyte, and particularly to improving the moisture resistance of the capacitor.

That is, it is intended to minimize changes in capacitor characteristics such as capacitance, tan δ, and leakage current (LC) over time in a high-humidity atmosphere.

Conventionally, solid electrolytic capacitors are manufactured by anodizing an anode body such as a plate, sintered body, foil, or rod of Kuntal, niobium, titanium, or aluminum, forming a dielectric anodic oxide film on its surface, and On the surface of the film, a pyrolyzable metal salt solution,
For example, manganese nitrate is thermally decomposed at 200 to 300°C to form a manganese dioxide solid electrolyte layer, and finally a cathode conductive layer is provided using colloidal carbon, silver paint, and solder, and then placed in a metal case or tipped in epoxy resin. The exterior was manufactured using transfer molding.

However, especially in the case of manganese dioxide,
MnO2 obtained by thermal decomposition of manganese nitrate at 200 to 300°C is β-type or α-Mn203, and these have the property of absorbing some amount of moisture in the air.

In fact, depending on the type of pyrolysis furnace used during pyrolysis, the resulting manganese dioxide layer is highly porous, which promotes moisture absorption.

Figure 1A shows the amount of water absorbed by manganese dioxide as an increase in its weight over time, and it can be seen that a considerable amount of water is absorbed by manganese dioxide.

By the way, when manganese dioxide, which is a solid electrolyte, absorbs moisture in the air, the capacitor's electrical characteristics change greatly from their initial values, and the overall performance tends to deteriorate.

In other words, from the point of view of capacitance, the water absorbed by manganese dioxide is absorbed by Ta which is not covered by manganese dioxide.
2O3 surface (Ta205 is not necessarily coated by 100% due to thermal decomposition.

) and dissolves CO2 and other impurity elements in the air, which itself acts as an electrolyte, increasing the capacitance of the entire capacitor.

However, because of the high polarity of water, the tan δ becomes large, and the capacitance fluctuates from the initial product value due to humidity, making it impossible to use it in circuits that require precision.

Furthermore, if highly polar water mixes into the manganese dioxide, the tan δ of the capacitor will increase, and naturally the frequency characteristics of the capacitor will deteriorate.

From the LC point of view, this is not preferable as it may cause short circuits.

On the other hand, with the recent development of electronic circuits and the trend towards miniaturization, the field of use of solid electrolytic capacitors is expanding, and the environment in which they are used must be able to withstand use in environments ranging from extremely low temperatures to high temperatures, and even in high humidity environments. It has been.

These requirements are particularly severe for high-precision circuits, and capacitors with high moisture resistance and high performance are required.

Among the above-mentioned packaging methods, the metal case and hermetic seal type shield the capacitor element from the outside air and have excellent moisture resistance, thus satisfying the above requirements to some extent.

However, the hermetic sealing process is quite complicated and is disadvantageous in terms of cost.

Above all, it is extremely difficult to make small capacitors for use in small electronic circuits.

There are other packaging methods, such as epoxy resin dip and epoxy mold packaging, but these all have problems with the moisture resistance and water absorption of the epoxy resin, and currently efforts are being made to develop highly moisture resistant epoxy resins. Although various countermeasures have been devised, the problem remains unresolved.

Furthermore, leadless chip capacitors for microcircuits, such as electronic watches and hearing aids, which have attracted particular attention in recent years, are designed without external packaging, in terms of the space available for the circuits used, and in terms of volumetric efficiency. Ideally, such products would be used in the industry, and some such products are beginning to become commercially available.

It goes without saying that such chip-type capacitors also require moisture resistance, and the water absorption of the manganese dioxide solid electrolyte becomes an issue.

As mentioned above, improving the moisture resistance of solid electrolytic capacitors is one of the most important issues among the various capacitor problems that need to be solved, and improving the moisture resistance of solid electrolytes of semiconducting manganese oxide is the most effective. seems to be an appropriate solution.

In view of the above-mentioned current situation, the present invention relates to a method for manufacturing a solid electrolytic capacitor having semiconducting manganese oxide with high moisture resistance.

More specifically, during the thermal decomposition of the thermally decomposable metal salt solution, an inorganic substance impregnated and supported with a trace amount of a polymer of an organosilicon compound (hereinafter referred to as silicone) is mixed and added into the thermally decomposable metal salt solution. The present invention relates to a solid electrolytic capacitor in which a semiconductor manganese oxide layer is thermally decomposed to form a semiconducting manganese oxide layer with high humidity resistance and high water repellency, and a method for manufacturing the same.

The specific content of the present invention will be described below.

If first, the properties of silicone will be described in detail.

Generally, silicone has a chemical structure like this or a three-dimensional structure,
Depending on the degree of polymerization, it has a liquid or solid form.

Although there are some differences, as can be seen from this chemical formula, it is water repellent and has very low water absorption.

For example, those commonly used for molding compounds have very low water absorption rates of 0.05 to 0.
08%, and the boiling water absorption rate is also around 0.3%.

The water vapor transmission rate also has a low value.

The present invention attempts to utilize such water resistance of silicone.

Below, the solid electrolytic capacitor of the present invention and its manufacturing method will be explained step by step.

Valve metal (Tantalum will be taken as an example below.

) A dielectric anodic oxide film is formed on the surface of the anode body (sintered body, foil, rod, plate) by an anodization method.

The above anode body was prepared using a thermally decomposable metal salt solution (hereinafter referred to as Mn(NO3
)2 is a representative example) and thermally decomposed at 200 to 300°C to form Mi102.

This operation is repeated as many times as necessary, and finally, colloidal carbon, Ag-paint-solder, etc. are applied as a cathode conductive layer.

Next, the type of silicone, the method of adding it to Mn(NO3)2, the properties of the Mn(NO3)2 liquid to which silicone is added, and the properties of the produced MnO2 will be described.

The silicones and mixtures thereof used in the present invention are in the form of fine powders or granules made of inorganic substances impregnated and supported at relatively high temperatures with silicones having a relatively high degree of polymerization.

Suitable inorganic substances include silicon oxide, aluminum oxide, calcium oxide, magnesium oxide, titanium oxide, kuntal oxide, manganese oxide, etc., which act as silicone stabilizers as described below.

That is, silicone with a high degree of polymerization by itself is difficult to uniformly disperse in an aqueous solution of manganese nitrate or the like.

The reason for this is that silicone itself has water repellency and low specific gravity.

For this reason, it becomes difficult for silicone to be uniformly dispersed in the generated MnO2 electrolyte, but in order to prevent such non-uniform dispersion and increase the water resistance of MnO2, the above-mentioned inorganic substance is used as a uniform dispersion aid. Add.

Furthermore, since Mn(NO3)2 undergoes a thermal decomposition reaction at a high temperature of 200 to 300 DEG C., it is necessary to add an inorganic substance as a support agent to stabilize the silicone at such high temperatures.

Furthermore, in addition to acting as silicone stabilizer and dispersant, the inorganic substance also plays the following roles.

Generally, the thermal decomposition temperature of silicone for the present invention is 40
Since the temperature is 0°C to 500°C, the silicone added during the thermal decomposition of manganese nitrate (200°C to 300°C) should not be thermally decomposed.

However, manganese dioxide produced by thermal decomposition has the property of a catalyst that promotes the oxidative decomposition reaction of polymers, and therefore, even at low temperatures of 200 to 300°C, in the presence of MnO2, silicone becomes silane, disilane, etc. As shown in FIG. 2, it was found that only carbon and 5i-022 remained in MnO21.

The various inorganic substances mentioned above include silicone, :! l:M110
It moderately suppresses direct contact with silicone and serves to prevent promotion of oxidative decomposition reaction of silicone.

As described above, silicone is applied in the form of powder or granules made of an inorganic substance impregnated with silicone.
It is possible to add it to the O3 solution, which causes MnO
A major feature of the present invention is that it remains in the water repellent and has water repellency.

The inorganic substance impregnated with silicone is gradually added to manganese nitrate and thoroughly stirred and dispersed using a dispersion mill, a mixer, or the like.

There is an appropriate range for the amount added as shown below.

In other words, since foreign substances such as silicone and inorganic substances are added to the MnO2 solid electrolyte, if the amount of these substances added is too large, the resistance and tanδ of MnO2 will increase.
This is undesirable because the properties of the solid electrolyte described in No. 2 will be impaired.

Unfortunately, if the amount added is too small, MnO2
Water resistance is reduced and no significant effect can be expected.

Figure 3 shows the relationship between the amount of inorganic material impregnated and supported with silicone and the initial tan δ of the capacitor.
When an inorganic material impregnated and supported with one or more strips of silicone is added, tan δ increases.

As will be explained later, if the amount added is less than 0.0001%, the effect will not be noticeable.

Therefore, the optimum amount of silicone and inorganic material to be added is 0.0001 to 1 weight year.

When manganese nitrate to which an inorganic substance impregnated and supported with silicone is added is thermally decomposed, a manganese dioxide layer as shown in FIG. 4 is formed.

That is, on the surface of a dielectric anodic oxide film (Ta205) 4 formed on the surface of an anode body 3 such as tantalum, an inorganic substance 6 such as SiO2 impregnated and supported with silicone 5 serves as a core, and manganese dioxide Mn027 is surrounding this core. MnO2 particles 8 are generated.

During the thermal decomposition of MnO27, the silicone 5 causes an oxidative decomposition reaction using Mn027 as a catalyst as described above, but the inorganic substance 6 acts as an inhibitor of this reaction, and the silicone 5 existing on the surface of the inorganic substance 6 and the heat The silicone 5 extruded from the inorganic substance 6 by decomposition is not thermally decomposed into gases such as silane and disilane, and the silicone 5' has sufficient water repellency even if the degree of polymerization decreases somewhat.
MnO27 itself is present in the water and provides water repellency to MnO27 itself.

Of course, since the inorganic substance 6 impregnated and supported with the highly polymerized silicone 5 exists as a core, MnO
2 particles 8 has sufficient water repellency.

A large number of such MnO2 particles 8 gather together to form a solid electrolyte layer 9.

The portion in FIG. 1 shows the increase in weight of the solid electrolyte layer 9 due to water absorption as a change over time, and it is clear that the solid electrolyte layer 9 has low water absorption.

Further, FIG. 5A shows the X-ray diffraction results of the above-mentioned MnO27, but there is no change at all compared to the silicone-free MnO2 shown in FIG. 5B.

Generally, by thermal decomposition of manganese nitrate, M
When obtaining an nO2 layer, performance-satisfactory MnO2 cannot be obtained by performing immersion-pyrolysis only once.

This tendency is particularly strong when a porous anode such as a sintered body is used for the anode body 3, and it is necessary to repeat the dip pyrolysis cycle 3 to 12 times, depending on the size of the element.

In applying the method of the present invention, silicone-impregnated and supported inorganic substance-added manganese nitrate may be used for all of these thermal decompositions, but the first two Mn (NOs) liquids are additive-free, and only the last one is used. Even if an inorganic substance impregnated with silicone is added, the effect can be expected to be sufficient.

The concept of "tonoto" can be fully understood by looking at the examples described below.

Next, the effects of the present invention will be described while showing examples of the present invention.

On a Ta sintered body with a diameter of 2.5 inches and a height of 3 mm,
A 18V anodic oxide film is generated using the phosphoric acid solution of Part 1.

Next, a MnO2 layer is formed on the Ta205 film by thermal decomposition of 0.01% by weight of silica impregnated with silicone and supported on manganese nitrate (ψ-1,6).

Repeat this operation 3 to 5 times. Next, a cathode conductive layer is formed using colloidal carbon, silver paint, and solder, and after coating with resin, initial characteristics are measured.

Changes in characteristics over time are then recorded in a constant temperature and humidity chamber at 85° C. and 90% humidity.

Figures 6 to 8 compare these results with those for capacitors without silicone additives (indicated by broken lines).

As can be seen from these results, the rate of change in capacitance is almost the same for both as shown in Figure 6, but the increase in tan δ is greater in the silicone-added capacitor as shown in Figure 7. Large quantity is small.

In particular, from the point of view of variation, capacitors without additives tend to have large values and vary over time, whereas silicone-added capacitors converge to a low value and have less variation. becomes very small.

This is considered to be due to the difference in performance due to the difference in hygroscopicity of the produced MnO2 for the reasons mentioned above.

The same thing can be said about the LC values as shown in FIG. 8, and it can be said that the variations in silicone-added capacitors are becoming smaller.

What should be noted is that, as shown in FIG. 8, the LC of the silicone-added capacitor has decreased to a value lower than the initial value.

The number of additive-free products tends to increase.

In addition, what is shown by the dashed line in FIG. 8 is the one in which the surface of MnO2 is coated with silicone.
After 500 hours, the LC value became significantly larger than the initial value, indicating that there was a problem in terms of longevity.

Thus, by adding silicone, the moisture resistance of the capacitor is improved, and in particular, the moisture resistance of tan δ and LC are significantly improved.

Next, we will briefly discuss the thermally decomposable metal salt solution to which silicone is added.

Generally, Mn is used as a salt for achieving these purposes.
(NO3)2 is often used.

When the present invention is also applied to Mn (NO3) 2,
As mentioned above, the effect is remarkable.

On the other hand, the effects of the present invention can also be applied to ammonium nitrate-manganese hydroxide-manganese nitrate-water system slurry.

The thermally decomposable salt of this system is the MnO produced per thermal decomposition.
Since the amount of 2 is large, this method is particularly effective for reducing the number of times of thermal decomposition of large capacitors and the like.

Therefore, by applying the present invention, it is also possible to improve the moisture resistance of large capacitors.

A specific method of applying the present invention to this slurry will be described below.

Adding ammonia to manganese nitrate (body!'%10%)
Then, silica powder impregnated with silicone is added and stirred in the same manner.

In this case, with respect to stirring, the three components may be mixed at once, or the silicone-silica powder may be added and mixed first, and then ammonia may be mixed.

In any case, ammonium nitrate - manganese hydroxide -
A manganese nitrate-silicone impregnated and supported inorganic substance-aqueous thermally decomposable metal salt solution is produced, and since the liquid is in the form of a slurry, the dispersibility of the silicone is very good.

Moreover, even if this material is thermally decomposed, the MnO2 layer produced is
When wired, electrically silicone-free Mn(No 3)2,
This is the same as the thermal decomposition of silicone-added Mn(NO3)2, and the same effect on moisture resistance can be expected as in the case of using Mn(NO3)2.

Next, a modification of the method of the present invention will be described below.

? The modification method of C is to apply colloidal carbon to a manganese dioxide layer containing silicone, cover the outer surface of the element with silicone, and then provide a cathode with silver paint or solder, or apply silicone to the manganese dioxide layer and then cover it with colloidal carbon. This method uses carbon, silver paint, or solder to provide the cathode.

In general, silver in silver paint has the property of diffusing in manganese dioxide under high temperature and high humidity and reaching the Ta205 film, and this is the reason why LC increases in humidity.

According to the method of dispersing silicone in manganese dioxide, which is the most important point of the present invention, as mentioned above, the water repellency and water resistance of manganese dioxide itself are improved, and the dispersion of manganese dioxide from Ag under high humidity improves. Needless to say, diffusion into the interior is sufficiently prevented.

However, in addition to this method, by covering the manganese dioxide layer with silicone and applying silver paint over it, Ag and MnO2 are further isolated, and the effect on the moisture resistance of the capacitor is as follows. Something even bigger is coming.

In other words, by covering the outer surface of the MnO2 layer with high moisture resistance and low water absorption with water-repellent silicone,
This means that there is almost no contact between the outside air moisture and the element body.

However, it is important to note that coating with silicone
This is effective for the silicone-dispersed MnO2 described in the present invention, and even if a conventional additive-free MnO2 layer is coated with silicone, no significant effect on moisture resistance can be expected.

Furthermore, since a foreign material film is interposed between the manganese dioxide and the Ag paint conductive layer, tan δ also increases.

Since the silicone film is formed at room temperature,
Considering the vaporization of silicone outside the capacitor element and deformation due to decomposition of the molecular weight of silicone when the element is heated to high or low temperatures, the temperature characteristics also deteriorate.

On the other hand, in the method of the present invention, in which silicone is mixed in Mn(N03)2 in advance during firing of Mn(NO3)2, there is no need to worry about such points.

For the above reasons, the moisture resistance can be further improved by using the above three methods in combination.

Next, application of the method of the present invention to a chip-type capacitor without an exterior will be specifically described.

As mentioned above, as electronic circuits become smaller, exterior packaging with metal cases, epoxy molds, etc. are no longer always satisfactory from the viewpoint of space factors.

However, in terms of circuit accuracy, stability in the performance of individual components is also required, and in the case of capacitors in particular, good moisture resistance is an essential condition.

Many of the microchip capacitors currently on the market are of the epoxy mold type, and do not yet completely satisfy the above requirements.

Therefore, when the method of the present invention is applied to an ultra-small capacitor,
There is an advantage in that the moisture resistance characteristics can be expected to be improved even if the element is not packaged, and this will be explained in detail below.

For example, an anode body 3 that has been press-molded and sintered into an ultra-small size is used as the anode body 3, and after forming the anodic oxide film 4, Mn A cathode conductive layer 10 is formed using the 02 layer 9, colloidal carbon, silver paint, and solder.

Then, the bare solder is used in the circuit without any external packaging such as epoxy molding.

An example of the chip condenser manufactured in this way is shown in the 9th section.
As shown in the figure, there is no increase in capacitor volume due to the exterior,
Large capacity per volume.

Since it has a solid electrolyte layer 9 of MnO2 that hardly absorbs moisture, the cathode solder part 10 (generally has almost no moisture resistance).

) is exposed, it has very good moisture resistance as a capacitor.

In the figure, 11 is an anode lead, and 12 is an anode current collector.

Next, some specific examples of the present invention will be described.

**Example
1. On a Ta sintered body having a diameter of 2.5 mrn and a height of 3 vtm, an 18 V anodic oxide film is formed with a 0.1% phosphoric acid solution.

Next, a MnO2 layer is formed on the Ta205 film by thermal decomposition of manganese nitrate (ψ-1,6) to which silicone-impregnated and supported silica powder is added at a weight of 0.01% and 1.0.1%.

Repeat this operation 3 to 5 times.

Next, a cathode conductive layer is formed using colloidal carbon, silver paint, and solder, and a resin exterior is applied.

Table 1 shows the initial characteristics and the characteristics of 856C after being stored in a constant temperature and humidity chamber at 90% humidity for about 500 hours in comparison with the characteristics of a capacitor using manganese nitrate without silicone additives.

Example 2 0.1% on a Ta sintered body with a diameter of 25 mrn and a height of 3 mm
A 18V anodic oxide film is produced using phosphoric acid solution.

Next, by thermal decomposition of manganese nitrate (ψ=1.6), Mn
Form an O2 layer.

Perform this operation twice. And finally, manganese nitrate (
Mn
02 layer is formed on the droplet*-generated MnO2 layer.

Next, a cathode conductor layer is formed using colloidal carbon, silver paint, and solder, and a resin exterior is applied.

Table 2 shows the initial characteristics and the characteristics after 500 hours of storage in a constant temperature and humidity chamber at 85°C and 90 layers of humidity. The following shows a comparison with the characteristics of a device made using the same method.

Example 3 0.1 mrn on a Ta sintered body with a diameter of 2.5 mrn1 and a height of 3 mrn
% phosphoric acid solution to produce a 18V anodic oxide film.

Next, 0.01% by weight of silica powder impregnated with silicone was added to a slurry made by adding 10 parts by volume of ammonia (28%) to manganese nitrate, and the mixture was thermally decomposed to form an MnO2 layer. form.

According to this method, the amount of MnO2 produced per one thermal decomposition is large, so one or two thermal decompositions are sufficient*.

Next, a cathode conductive layer is formed using colloidal carbon silver paint and solder, and a resin exterior is applied.

Table 3 shows the initial characteristics and the characteristics after 500 hours of storage in a constant temperature and humidity chamber at 85° C. and 90 relative humidity in comparison with the characteristics of a condenser using a silicone-free ammonium nitrate-manganese hydroxide-manganese nitrate-water slurry.

Example 4 0.1% on a Ta sintered body with a diameter of 2.5 mm and a height of 3 dragons
A 18V anodic oxide film is produced using phosphoric acid solution.

Next, a MnO2 layer is formed on Ta2O5 by thermal decomposition of a manganese nitrate solution (ψ-1,6) to which 0.01% by weight of silica powder impregnated and supported with silicone is added.

Repeat this operation 3 to 5 times. Next, a cathode conductive layer is formed using rhoidal carbon, silver paint, and solder to form a solid electrolytic capacitor with the structure shown in Figure 9.

Table 4 shows the initial characteristics and the characteristics after 500 hours of storage in a constant temperature and humidity chamber at 85°C and 90% humidity, in comparison with the characteristics of a capacitor using manganese nitrate without silicone additives.

Example 5 0.1 on a Ta sintered body with a diameter of 2.5 am and a height of 3 mm
% phosphoric acid solution to produce a 18V anodic oxide film.

A MnO2 layer is formed on Ta2O5 by thermal decomposition of a manganese nitrate solution (ψ-1,6) to which 0.01% by weight of silicone-impregnated supported silica powder is added.

Repeat this operation 3 to 5 times. Next, colloidal carbon is applied, and the device is dipped in a solution of silicone dissolved in an appropriate diluent. After the diluent is vaporized, a cathode is formed using silver paint and solder, and finally, a resin exterior is applied.

Table 5 shows the initial characteristics and the characteristics after 500 hours of storage in a constant temperature and humidity chamber at 85°C and 90% relative humidity, in comparison with the characteristics of a capacitor using manganese nitrate without silicone additives and a capacitor without silicone coating.

As described above, according to the present invention, it is possible to impart absorption resistance and water repellency to a semiconductor manganese oxide without impairing its electrical properties, thereby achieving improvement in the moisture resistance characteristics of a capacitor.

Furthermore, by applying the present invention to a microchip capacitor that requires a small space factor, it is possible to improve moisture resistance and downsize the capacitor, and the effects are extremely significant.

[Brief explanation of the drawing]

Figure 1 shows M in solid electrolytic capacitors of the conventional and the present invention.
A characteristic diagram showing the increase in weight of nO2 due to water absorption over time. Figure 2 shows MnO2 obtained by simply adding silicone to a pyrolyzable metal solution and thermally decomposing it at an intermediate stage leading up to the present invention.
FIG. 3 is a characteristic diagram showing the relationship between the amount of silicone impregnated and supported inorganic material added and tan δ in the present invention, and FIG.
The figure is an enlarged sectional view of the main parts of the solid electrolytic capacitor of the present invention.
FIG. 5A is a characteristic diagram showing the X-ray diffraction results of MnO2 according to the present invention, FIG. 5B is a characteristic diagram showing the conventional X-ray diffraction results of MnO2, and FIG. 6 is a characteristic diagram showing the X-ray diffraction results of MnO2 according to the present invention. Figure 7 is the capacitance change rate characteristic diagram of the capacitor, and Figure 8 is the same CR characteristic diagram.
This figure is a leakage current characteristic diagram, and FIG. 9 is a perspective view showing one embodiment of a chip type solid electrolytic capacitor according to the present invention. Total: Anode body, 4: Dielectric anodic oxide film, 5.5': Silicone, 6:...
Inorganic substance, 7...MnO2, 9...solid electrolyte, 10...cathode conductive layer.

Claims (1)

[Scope of Claims] 1. A fine powder or granular inorganic material impregnated and supported with a polymer of an organosilicon compound, which is formed by forming a dielectric anodic oxide film on the surface of an anode body made of a valve metal by anodization. A solid electrolyte layer made of semiconducting manganese oxide is formed by immersion in a thermally decomposable metal salt solution to which is added, and this is thermally decomposed to form a solid electrolyte layer made of semiconducting manganese oxide, and colloidal carbon,
A method for manufacturing a solid electrolytic capacitor characterized by providing a cathode conductive layer using silver paint, solder, etc. 2. A method for producing a solid electrolytic capacitor according to claim 1, wherein a polymer of an organosilicon compound impregnated and supported by an inorganic substance is supported in a semiconducting manganese oxide. 3. A method for producing a solid electrolytic capacitor according to claim 1, comprising forming a polymer layer of an organosilicon compound on a solid electrolyte supporting a polymer of an organosilicon compound or a colloidal carbon layer on the solid electrolyte. . 4. The method for manufacturing a solid electrolytic capacitor according to claim 2, wherein oxides of silicon, aluminum, calcium, magnesium, titanium, manganese, and tantalum are used as the inorganic substances. 5. The method for manufacturing a solid electrolytic capacitor according to claim 1, characterized in that a manganese nitrate solution is used as the thermally decomposable metal salt solution. 6. The method of manufacturing a solid electrolytic capacitor according to claim 1, wherein a slurry of ammonium nitrate-manganese hydroxide-manganese nitrate-water system is used as the thermally decomposable metal salt solution. 7 As an inorganic substance impregnated and supported with an organosilicon compound,
2. The method for producing a solid electrolytic capacitor according to claim 1, wherein 0.0001 to 1 weight factor is added to the thermally decomposable metal salt solution. 8. The method for manufacturing a solid electrolytic capacitor according to claim 1, wherein after forming the solid electrolyte layer, a film of an organosilicon compound is formed, and a cathode conductive layer is formed thereon. 9. After forming a solid electrolyte layer and a colloidal carbon layer, a coating of a polymer of an organosilicon compound is provided, and then a cathode conductive layer is provided using silver paint, solder, etc. A method for manufacturing a solid electrolytic capacitor according to item 1.