JP4985136B2 - SOLID ELECTROLYTIC CAPACITOR, SUBSTRATE WITH SOLID ELECTROLYTIC CAPACITOR AND METHOD FOR PRODUCING THEM - Google Patents

Description

  The present invention relates to a solid electrolytic capacitor, a substrate incorporating the solid electrolytic capacitor, and a method for manufacturing the same.

  In recent years, with the digitalization and high definition of television, LSIs that process image signals at high speed have been demanded. The LSI is packaged together with a CPU, a RAM bus, an interface, and the like, and is mounted on various electronic devices as a system LSI.

  The CPU is supplied with power from an external AC power supply via a power line via an AC-DC converter and a DC-DC converter. Then, when switching from OFF to ON, the CPU cannot instantaneously recover the voltage with only the current from the power supply line instantaneously, and the actual processing speed of the CPU decreases. Therefore, in general, a capacitor is connected in parallel with the power supply line in order to compensate for an instantaneous current shortage of the CPU and to promptly restore the voltage.

  The characteristics required for this capacitor are mainly large capacity and low ESL.

  Conventionally, in such a solid electrolytic capacitor, an anode foil and a three-terminal capacitor anode, a cathode foil, and the like are formed by using a conductive paste or the like in which an anode foil and a cathode foil are spaced apart in the horizontal direction and passed through a through hole A three-terminal capacitor cathode is electrically joined (Patent Document 1).

Further, the mounting substrate on which the capacitor is mounted is also required to be thin. In order to satisfy this requirement, a method of embedding a capacitor as a surface-mounted component in a mounting substrate is also considered (Patent Document 2).
JP 2003-158042 A JP 2003-197849 A

  However, there is a problem that such a conventional low ESL solid electrolytic capacitor is not suitable for a large capacity.

  That is, in the above-described conventional configuration, the anode foil and the cathode foil are separated from each other for the purpose of shortening the length of the cathode lead wire in order to realize low ESL. For this reason, the three-terminal capacitor anode and the three-terminal capacitor cathode cannot be present at opposite positions, and the structure is not suitable for increasing the capacity.

  Further, since it is necessary to secure the extraction electrode portion by reducing the thickness, the capacity as the capacitor cannot be secured by reducing the volume as the capacitor.

In order to solve the above-described problems, the present invention provides a first through hole formed in a part of the valve metal foil at least in a part of the valve metal foil having a porous portion having a dielectric film formed on the surface thereof. In addition, a first insulating layer is formed on the inner wall of the first through-hole, and a positive-cathode separating portion made of the second insulating layer is provided. A solid electrolytic capacitor electrically insulated from an electric conductor layer, wherein at least one floating island-shaped third insulating layer formed on a part of the dielectric film, and the third insulating layer A solid electrolyte layer formed on the dielectric coating in the outer portion of the layer; and a current collector layer formed on the upper surface of the solid electrolyte layer, wherein a part of the first insulating layer is not formed. 3, the third insulating layer, the dielectric coating under the third insulating layer, and the anode are penetrated. A second through hole is provided, and a third through hole penetrating the first insulating layer is provided in the first through hole in which the first insulating layer is formed, and the second through hole is provided. and it a solid electrolytic capacitor, wherein the at least one through-wiring to the floating island of the third insulating layer portion is formed by the through-hole electrode is provided in the third through hole, wherein The surface of the dielectric coating has a porous portion that is made porous, and the second insulating layer and the third insulating layer fill the surface of the dielectric coating and the inside of the porous portion, The solid electrolytic capacitor is characterized in that the first through hole penetrates the second insulating layer and the third insulating layer .

  In the solid electrolytic capacitor of the present invention, a solid electrolyte layer can be formed outside at least one or more floating island-shaped third insulating layers, and the inside of at least one or more floating island-shaped third insulating layers. The through-wiring can be formed in the wiring, so that the degree of freedom of wiring can be increased, and since the capacitor can be freely formed in places other than the wiring, the capacity can be increased, so a high-speed IC / LSI is used. This contributes to higher functionality and downsizing of equipment.

(Embodiment 1)
Hereinafter, the solid electrolytic capacitor according to Embodiment 1 of the present invention will be described with reference to the drawings.

  1 is a cross-sectional view of a solid electrolytic capacitor according to the present invention, FIG. 2 is a plan view of the solid electrolytic capacitor according to the present invention in the AA ′ direction of FIG. 1, and FIG. It is a top view of a BB 'direction.

  A valve metal foil 1 serving as an anode shown in FIG. 1 is made of a material such as Al, Ta, Nb, or an alloy thereof, and forms a dielectric film 2 having a porous surface by a technique such as chemical treatment. By using the valve metal foil 1, a dielectric coating can be easily formed. Further, by forming the dielectric coating 2, the capacity can be increased.

  Here, the first insulating layer 3 has a function of electrically insulating the valve metal foil 1 and the first through-hole electrode 8. As the first insulating layer 3, an epoxy resin, a phenol resin, a silicon resin, or the like can be used.

  Here, the second insulating layer 4 and the third insulating layer 14 are filled in the surface of the dielectric coating 2 and the inside of the porous portion to prevent the solid electrolyte layer 5 from spreading and the first through hole. It also has an effect of preventing the inflow of a plating solution or the like when forming the electrode 8 and the second through-hole electrode 9.

  Here, the solid electrolyte layer 5 is formed on the dielectric coating 2. The solid electrolyte layer 5 can be formed by chemical polymerization or electrolytic polymerization of a functional polymer made of pyrrole, thiophene, or the like. Since the interface resistance is low, the ESR can be reduced.

  Here, the current collector layer 6 serving as the cathode portion is formed on the solid electrolyte layer 5 and is formed, for example, by applying and curing an Ag paste.

  Here, the first through-hole electrode 8 is formed inside the second through hole 7 where the first insulating layer 3 is not formed, and is formed so as to be electrically connected to the valve metal foil 1. And can be taken out to the surface layer.

  Here, the second through-hole electrode 9 is formed in a portion where the third through hole 15 in which the first insulating layer 3 is formed and is electrically insulated from the valve metal foil 1. Has been.

  In addition, the second through-hole electrode 9 may be electrically connected to the current collector layer 6 through the wiring 10. When the second through-hole electrode 9 is electrically connected, the second through-hole electrode 9 is , Function as a cathode. Further, when the second through-hole electrode 9 is not electrically connected to the current collector layer 6, it functions as a part of the upper and lower through-hole wiring, and the degree of freedom of wiring can be increased.

  Here, Ni-Cu plating, Cu plating, or the like is suitable as the configuration of the through-hole electrode.

  Here, the wiring 10 is a metal layer formed by plating or the like, and is patterned by etching or the like. High-density wiring can be realized by patterning. As a metal of the wiring 10, Cu is suitable in view of patterning property and conductivity.

Here, in the top view of the AA ′ portion (that is, the solid electrolyte layer 5 forming portion) in FIG. 2, the solid electrolyte layer 5 can be formed in the peripheral portion of the floating island-shaped third insulating layer 14. . Thereby, it is possible to form a through wiring in the interior of the third insulating layer 14 floating island-like, it is possible to increase the degree of freedom of the wiring, also, since the freely possible to form a capacitor at other than the wiring The capacity can be increased. Further, where the through wiring is formed in the portion where the first insulating layer 3 is formed, it is electrically insulated from the anode.

  Here, in the BB ′ portion of FIG. 3 (that is, 1 part of the valve metal foil), the second through-hole electrode 9 is formed by forming the first insulating layer 3 after forming the through hole. It is electrically insulated from the valve metal foil 1, and positive and negative electrode separation can be realized.

  For example, carbon or the like may be applied between the solid electrolyte layer 5 and the current collector layer 6.

  For example, after forming the first through-hole 12, the second through-hole 7, and the third through-hole 15, repair formation is performed to improve capacitor characteristics, and leakage current in the through-hole forming portion is reduced. May be.

  In addition, the 1st through-hole electrode 8 and the 2nd through-hole electrode 9 may be filled-plated, and may be filled with resin.

(Embodiment 2)
The following describes the solid electrolytic capacitor built-in substrate according to Embodiment 2 of the present invention with reference to the drawings. In addition, about the thing which has the structure similar to the structure of Embodiment 1, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  4 is a cross-sectional view of the solid electrolytic capacitor built-in substrate according to the present invention, FIG. 5 is a plan view of the solid electrolytic capacitor built-in substrate according to the present invention in the direction CC ′ of FIG. 4, and FIG. FIG. 6 is a plan view of a built-in substrate in the direction DD ′ of FIG. 4.

  In FIG. 4, the second through-hole electrode 9 is formed on the inner wall of the first insulating layer 3 and is electrically connected to the current collector layer 6 serving as the cathode by the wiring 10, but the valve serving as the anode. The cathode wiring layer can be formed by adopting a configuration that is not electrically connected to the metal foil 1.

  The first through-hole electrode 8 is formed, and is electrically connected to the valve metal foil 1 serving as the anode by the wiring 10 but is not electrically connected to the current collector layer 6. Thus, the anode wiring layer can be formed.

  A third through-hole electrode 11 is formed on the first insulating layer 3 so that the capacitor is not electrically connected to the anode and the cathode, and the wiring 10 is electrically connected to the valve metal foil 1 and the current collector layer 6. A through wiring layer can be formed by adopting a structure that is not connected to the wiring. By doing so, the freedom degree of wiring can be improved.

  Here, in the CC ′ portion of FIG. 5 (that is, the solid electrolyte layer 5), for example, a capacitor is formed in a free space outside the anode wiring layer and the cathode wiring layer, thereby realizing a large capacity. be able to.

  Here, in the DD ′ portion of FIG. 6 (that is, 1 part of the valve metal foil), the through wiring and the cathode wiring part are electrically connected to the valve metal foil 1 by forming the first insulating layer 3. It is possible to insulate.

  For example, carbon or the like may be applied between the solid electrolyte layer 5 and the current collector layer 6.

  For example, after the second through hole 7 is formed, repair formation may be performed to improve the characteristics of the capacitor to reduce the leakage current in the through hole forming portion.

  Note that the first through-hole electrode 8, the second through-hole electrode 9, and the third through-hole electrode 11 may be filled-plated or filled with resin.

  Note that a higher density of wiring may be realized by further building up the solid electrolytic capacitor built-in substrate.

  In addition, even if high density wiring is realized by combining at least one surface of the substrate with a built-in solid electrolytic capacitor with a high-density wiring board via an uncured resin and electrically connecting through through-hole plating or the like. Good.

(Embodiment 3)
Hereinafter, the manufacturing method of the solid electrolytic capacitor of this invention is demonstrated, referring drawings.

  7 (a) to (c), FIGS. 8 (a) and (b), FIGS. 9 (a) and (b), FIGS. 10 (a) and (b), and FIG. 11 (a) are the third embodiment of the present invention. It is a cross-sectional process drawing which shows the manufacturing method of the solid electrolytic capacitor as described in 1 above. Components having the same configuration as that of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 7 (a) First, a valve metal foil 1 on which a dielectric coating 2 is formed is prepared. The dielectric coating 2 may be formed on one side or both sides of the valve metal foil 1.

  Next, an uncured second insulating layer 4 and at least one floating island-shaped third insulating layer 14 are formed on the portion of the valve metal foil 1 where the solid electrolyte layer is not formed. , Cure. As a technique, a technique such as inkjet printing or screen printing can be used.

  Next, a first through hole 12 is formed in the valve metal foil 1. As a technique, a technique such as drilling, laser machining, punching, or cutting with a die can be used. At this time, the repair formation may be performed on the first through hole 12.

  Next, the first insulating layer 3 made of epoxy resin, phenol resin, silicon resin or the like is formed on the inner wall of the first through hole 12 and cured.

  Next, the solid electrolyte layer 5 is formed on the portion of the dielectric coating 2 where the second insulating layer 4 is not formed. The solid electrolyte layer 5 can be formed by using a polymerization method. As an example of the polymerization method, for example, there is a method of chemical polymerization in which a chemical solution containing thiophene is applied and cured. After the chemical polymerization, the solid electrolyte layer 5 may be grown by further electrolytic polymerization.

  Next, after applying an Ag paste or the like on the solid electrolyte layer 5, the current collector layer 6 is formed by curing. As a technique, a transfer method, a screen printing method, or the like is used.

  Next, the metal layer 13 is formed on the surface layer by plating. As a metal, Cu is suitable in view of patterning property and conductivity. As an example of the plating method, dry desmear treatment or wet desmear treatment is performed, the second insulating layer 4 is made uneven, nucleated with Pd, etc., and then formed in the order of electroless plating and electrolytic plating. can do.

  10 (a) Next, by drilling or the like, (1) metal layer 13, third insulating layer 14, dielectric coating 2, valve metal foil 1, dielectric coating 2, second insulating layer 4, metal A second through hole 7 that penetrates the layer 13 is formed. In addition, (2) the metal layer 13, the first insulating layer 3, and the third through hole 15 that penetrates the metal layer 13 are formed at the same time. The second through hole 7 and the third through hole 15 may be formed separately.

  Next, plating is performed on the second through-hole 7 and the third through-hole 15 by a plating method, and (1) a second through-hole electrode 9 and (2) a first through-hole electrode. 8 is formed. As an example of the plating method, for example, when the valve metal foil 1 is aluminum, a zincate treatment is performed, and after Al is replaced with Zn, a technique such as Ni plating or Cu plating is used. In addition, the inner wall of the second through hole 7 and the third through hole 15 is subjected to dry desmear treatment or the like before the zincate treatment, thereby improving connection reliability.

  11A, after forming the metal layer 13, the wiring 10 is formed by performing a normal wiring pattern forming process such as resist formation-exposure-development-etching. By doing so, the first through-hole electrode 8 and the second through-hole electrode 9 are electrically insulated. The first through-hole electrode 8 can form an extraction electrode as an anode. When the second through-hole electrode 9 is electrically connected to the current collector layer 6, the first through-hole electrode 8 can function as a cathode. When the through-hole electrode 9 is electrically insulated from the current collector layer 6, it can function as a through wiring layer, and the degree of freedom of wiring can be improved.

  By this manufacturing method, the solid electrolytic capacitor of the present invention can be easily manufactured.

(Embodiment 4)
Hereinafter, the manufacturing method of the board | substrate with a built-in solid electrolytic capacitor of this invention is demonstrated, referring drawings.

  FIGS. 12A to 12C, FIGS. 13A and 13B, FIGS. 14A and 14B, FIGS. 15A and 15B, and FIG. 16A are the fourth embodiment of the present invention. It is a cross-sectional process drawing which shows the manufacturing method of the solid electrolytic capacitor as described in 1 above. Components having the same configuration as that of the second embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 12 (a) First, a valve metal foil 1 on which a dielectric coating 2 is formed is prepared. The dielectric coating 2 may be formed on one side or both sides of the valve metal foil 1.

  Next, an uncured second insulating layer 4 and at least one floating island-shaped third insulating layer 14 are formed on the portion of the valve metal foil 1 where the solid electrolyte layer is not formed. , Cure. As a technique, a technique such as inkjet printing or screen printing can be used.

  Next, the first through hole 12 is formed in the valve metal foil 1. As a technique, a technique such as drilling, laser machining, punching, or cutting with a die can be used. At this time, the repair formation may be performed on the first through hole 12.

  Next, the first insulating layer 3 made of epoxy resin, phenol resin, silicon resin or the like is formed in the first through hole 12 and cured.

  Next, the solid electrolyte layer 5 is formed on the portion of the dielectric coating 2 where the second insulating layer 4 is not formed. The solid electrolyte layer 5 can be formed by using a polymerization method. As an example of the polymerization method, for example, there is a method of chemical polymerization in which a chemical solution containing thiophene is applied and cured. After the chemical polymerization, the solid electrolyte layer 5 may be grown by further electrolytic polymerization.

  Next, after applying an Ag paste or the like on the solid electrolyte layer 5, it is cured to form the current collector layer 6. As a technique, a transfer method, a screen printing method, or the like is used.

  FIG. 14B Next, the metal layer 13 is formed on the surface layer by plating. As a metal, Cu is suitable in view of patterning property and conductivity. As an example of the plating method, dry desmear treatment or wet desmear treatment is performed, the second insulating layer 4 is made uneven, nucleated with Pd, etc., and then formed in the order of electroless plating and electrolytic plating. can do.

  15 (a) Next, by drilling or the like, (1) metal layer 13, third insulating layer 14, dielectric coating 2, valve metal foil 1, dielectric coating 2, third insulating layer 14, metal A second through hole 7 that penetrates the layer 13 is formed. In addition, (2) the metal layer 13, the first insulating layer 3, and the third through hole 15 that penetrates the metal layer 13 are formed.

  FIG. 15 (b) Next, the second through hole 7 and the third through hole 15 are plated by a plating method, and (1) the second through hole electrode 9 and (2) the first through hole electrode. 8 is formed. As an example of the plating method, for example, when the valve metal foil 1 is aluminum, a zincate treatment is performed, and after Al is replaced with Zn, a technique such as Ni plating or Cu plating is used. Further, the inner wall of the second through hole 7 and the third through hole 15 is subjected to a dry desmear process or the like before the zincate process, thereby improving connection reliability.

  16A, after forming the metal layer 13, the wiring 10 is formed by performing a normal wiring pattern forming process such as resist formation-exposure-development-etching. By doing so, the first through-hole electrode 8 and the second through-hole electrode 9 are electrically insulated. The second through-hole electrode 9 can form a take-out electrode as an anode, and can function as a cathode when the first through-hole electrode 8 is electrically connected to the current collector layer 6. When the third through-hole electrode 11 is electrically insulated from the current collector layer 6, it can function as a through wiring layer, and the degree of freedom of wiring can be improved.

  By this manufacturing method, the solid electrolytic capacitor built-in substrate of the present invention can be easily manufactured.

  As described above, the solid electrolytic capacitor of the present invention can form a solid electrolyte layer outside at least one or more floating island-shaped third insulating layers. As a result, through-wiring can be formed inside at least one floating island-shaped third insulating layer, the degree of freedom of wiring can be increased, and a capacitor can be freely formed outside the wiring. Therefore, the capacity can be increased, which contributes to higher functionality and downsizing of equipment using high-speed IC / LSI.

Sectional drawing of the solid electrolytic capacitor in Embodiment 1 of this invention FIG. 3 is a plan view of the solid electrolytic capacitor according to Embodiment 1 of the present invention. FIG. 3 is a plan view of the solid electrolytic capacitor according to Embodiment 1 of the present invention. Sectional drawing of the board | substrate with a built-in solid electrolytic capacitor in Embodiment 2 of this invention The top view of the board | substrate with a built-in solid electrolytic capacitor in Embodiment 2 of this invention The top view of the board | substrate with a built-in solid electrolytic capacitor in Embodiment 2 of this invention (A)-(c) is process sectional drawing which shows the manufacturing method of the solid electrolytic capacitor in Embodiment 3 of this invention (A), (b) is process sectional drawing which shows the manufacturing method of the solid electrolytic capacitor in Embodiment 3 of this invention (A), (b) is process sectional drawing which shows the manufacturing method of the solid electrolytic capacitor in Embodiment 3 of this invention (A), (b) is process sectional drawing which shows the manufacturing method of the solid electrolytic capacitor in Embodiment 3 of this invention (A) is process sectional drawing which shows the manufacturing method of the solid electrolytic capacitor in Embodiment 3 of this invention (A)-(c) is process sectional drawing which shows the manufacturing method of the solid electrolytic capacitor built-in board | substrate in Embodiment 4 of this invention. (A), (b) is process sectional drawing which shows the manufacturing method of the board | substrate with a built-in solid electrolytic capacitor in Embodiment 4 of this invention (A), (b) is process sectional drawing which shows the manufacturing method of the board | substrate with a built-in solid electrolytic capacitor in Embodiment 4 of this invention (A), (b) is process sectional drawing which shows the manufacturing method of the board | substrate with a built-in solid electrolytic capacitor in Embodiment 4 of this invention (A) Process sectional drawing which shows the manufacturing method of the solid electrolytic capacitor built-in board | substrate in Embodiment 4 of this invention.

DESCRIPTION OF SYMBOLS 1 Valve metal foil 2 Dielectric film 3 1st insulating layer 4 2nd insulating layer 5 Solid electrolyte layer 6 Current collector layer 7 2nd through-hole 8 1st through-hole electrode 9 2nd through-hole electrode 10 Wiring 12 First through hole 13 Metal layer 14 Third insulating layer 15 Third through hole

Claims (6)

At least a part of the valve metal foil having a porous portion having a dielectric film formed on the surface thereof, a first through hole is formed in a part of the valve metal foil, and a first through hole is formed on the inner wall of the first through hole. 1 has an anode-cathode separation portion formed of a second insulation layer, and a valve metal foil serving as an anode portion and a current collector layer serving as a cathode portion are electrically insulated. A solid electrolytic capacitor,
At least one floating island-shaped third insulating layer formed on a part of the dielectric coating; a solid electrolyte layer formed on the dielectric coating in an outer portion of the third insulating layer; A current collector layer formed on the upper surface of the electrolyte layer,
A second through-hole penetrating the third insulating layer, the dielectric coating under the third insulating layer, and the anode in a part of the third insulating layer portion where the first insulating layer is not formed Is provided,
A third through hole penetrating the first insulating layer is provided in the first through hole in which the first insulating layer is formed;
It met solid electrolytic capacitor, wherein the second and third through-holes through wiring on the third insulating layer portion of at least one of the floating-island by through-hole electrodes are provided is formed And
The surface of the dielectric coating has a porous portion that is made porous,
The second insulating layer and the third insulating layer fill the surface of the dielectric film and the inside of the porous portion,
The solid electrolytic capacitor, wherein the first through hole penetrates the second insulating layer and the third insulating layer. The solid electrolytic capacitor according to claim 1, wherein the second through hole and the third through hole are electrically insulated. The solid electrolytic capacitor according to claim 1, wherein the valve metal foil is made of aluminum, tantalum, niobium, or an alloy thereof. At least a part of the valve metal foil having a porous portion having a dielectric film formed on the surface thereof, a first through hole is formed in a part of the valve metal foil, and a first through hole is formed on the inner wall of the first through hole. 1 has an anode-cathode separation portion formed of a second insulation layer, and a valve metal foil serving as an anode portion and a current collector layer serving as a cathode portion are electrically insulated. A solid electrolytic capacitor,
At least one floating island-shaped third insulating layer formed on a part of the dielectric coating; a solid electrolyte layer formed on the dielectric coating in an outer portion of the third insulating layer; A current collector layer formed on the upper surface of the electrolyte layer,
A second through-hole penetrating the third insulating layer, the dielectric coating under the third insulating layer, and the anode in a part of the third insulating layer portion where the first insulating layer is not formed Is provided,
A third through hole penetrating the first insulating layer is provided in the first through hole in which the first insulating layer is formed;
A solid electrolytic capacitor characterized in that a through-hole wiring is formed in at least one of the floating island-shaped third insulating layer portions by providing through-hole electrodes in the second and third through-holes. And
The second insulating layer and the third insulating layer fill the surface of the dielectric film and the inside of the porous portion,
The first through hole has a built-in solid electrolytic capacitor that penetrates the second insulating layer and the third insulating layer to form an anode wiring / cathode wiring and a through wiring. A solid electrolytic capacitor built-in substrate. A first step of forming a second insulating layer and at least one or more floating island-shaped third insulating layers in a portion where the cathode portion of the valve metal foil serving as the anode portion is not formed;
A second step of forming a first through hole in the valve metal foil obtained in the first step;
A third step of forming a first insulating layer in the first through-hole obtained in the second step;
A fourth step of forming a solid electrolyte layer by a polymerization method at a site where the cathode portion of the valve metal foil obtained in the third step is formed;
Forming a conductive paste so as to cover the surface of the solid electrolyte layer obtained in the fourth step, and curing the conductive paste to form a current collector layer serving as a cathode;
A sixth step of plating the valve metal foil on which the second insulating layer and the conductive paste obtained in the fifth step are formed to form a metal layer;
The third insulating layer, the dielectric coating below the third insulating layer, and the anode are formed on a part of the third insulating layer where the first insulating layer is not formed on the valve metal foil obtained in the sixth step. A seventh step of providing a second through hole penetrating through the valve metal foil and forming a third through hole penetrating the first insulating layer in the first through hole;
An eighth step of performing through-hole plating on the second and third through holes obtained in the seventh step and electrically connecting to the metal layer;
A method of manufacturing a solid electrolytic capacitor having at least a ninth step of electrically insulating the second through hole and the third through hole by patterning the metal layer ,
In the first step, the valve metal foil has a dielectric coating having a porous surface, and the second insulating layer and the third insulating layer are formed on the surface of the dielectric coating and the porous portion. Filled inside,
In the second step, the first through hole penetrates the second insulating layer and the third insulating layer. A first step of forming a second insulating layer and at least one or more floating island-shaped third insulating layers on a portion of the valve metal foil serving as an anode where the cathode portion is not formed;
A second step of forming a first through hole in the valve metal foil obtained in the first step;
A third step of forming a first insulating layer in the first through hole obtained in the second step;
A fourth step of forming a solid electrolyte layer by a polymerization method at a site for forming the cathode portion of the valve metal foil obtained in the third step;
Forming a conductive paste so as to cover the surface of the solid electrolyte layer obtained in the fourth step, and curing the conductive paste to form a current collector layer serving as a cathode;
A sixth step of forming a metal layer by plating on the valve metal foil on which the second insulating layer, the third insulating layer and the conductive paste obtained in the fifth step are formed;
A part of the second insulating layer portion or the third insulating layer portion in which the first insulating layer is not formed on the valve metal foil obtained in the sixth step includes the third insulating layer and the third insulating layer. A third through hole is provided which has a second through hole penetrating the lower dielectric coating and the valve metal foil serving as the anode, and penetrates the first insulating layer in the first through hole. A seventh step of forming holes;
An eighth step of performing through-hole plating on the second and third through holes obtained in the seventh step and electrically connecting to the metal layer;
A method of manufacturing a substrate with a built-in solid electrolytic capacitor having at least a ninth step of electrically insulating the second through hole and the third through hole by patterning the metal layer ,
In the first step, the valve metal foil has a dielectric coating having a porous surface, and the second insulating layer and the third insulating layer are formed on the surface of the dielectric coating and the porous portion. Filled inside,
In the second step, the first through-hole penetrates the second insulating layer and the third insulating layer, and the method for manufacturing a substrate with a built-in solid electrolytic capacitor is characterized in that: