JP2008130778A - Capacitor element, manufacturing method of the same, and capacitor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a capacitor element including a large area of dielectric layer having a thin and uniform thickness, and to provide a capacitor. <P>SOLUTION: The capacitor element 10 of a first embodiment has a structure where a first electrode 15, having a plurality of columnar electrodes 15b, faces a second electrode 17, filled between the columnar electrodes 15b, by holding the dielectric layer 16 between them. Specifically, the first electrode 15 is composed of first valve metal and includes; the plurality of columnar electrodes 15b composed of the first valve metal; and an extraction electrode 15a connected to the respective one ends of the columnar electrodes 15b. The dielectric layer 16 is formed at least close to the surface of the columnar first electrodes 15b and composed of a valve metal oxide film. The second electrode covers the surface of the dielectric layer and filled in gaps between the columnar electrodes. Accordingly, the dielectric layer having the thin and uniform thickness is arranged between the first electrode and the second electrode. When the length of the columnar electrodes is increased, the facing areas are enlarges. Consequently, the small capacitor with a large capacity is provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a capacitor element that is small and can realize a large capacity, and a method of manufacturing the capacitor element.

Currently, Al electrolytic capacitors and multilayer ceramic capacitors are known as widely used capacitors. In the Al electrolytic capacitor, there are problems such as liquid leakage in order to handle the electrolytic solution. In addition, in the multilayer ceramic capacitor, the dielectric layer needs to be fired, and there are problems such as cracks due to the difference in thermal shrinkage between the electrode and the dielectric layer during the firing. A capacitor having a novel structure that avoids these problems is desired.
Further, although a thin film capacitor using a dielectric thin film has been proposed, there has been a problem that the surface area of the dielectric thin film cannot be increased, and a small and large capacity capacitor cannot be provided.

In order to solve these problems and increase the capacity, the following proposals have been made. Specifically, in Patent Document 1, as shown in FIG. 711, the planar electrode 45a on the capacitor substrate 3 is used with the porous substrate 2 provided with a large number of holes 2a as a mask as shown in FIG. A first electrode 5 in which a large number of columnar bodies 5ab are regularly arranged is formed on the surface of the first electrode 5 by thin film deposition or etching, and then a dielectric material having a dielectric constant of 100 or more is formed on the surface of the columnar first electrode. A dielectric thin film 6 is formed by forming a film by MOCVD (metal organic vapor phase epitaxy), and a second electrode 7 is formed on the surface of the dielectric thin film 6 to form a capacitor structure 1 as shown in FIG. The method of obtaining is proposed.

JP 2003-249417 A

  However, in the method for manufacturing the capacitor structure 1 according to the background art as described above, the columnar body 5b is formed using the porous substrate 2 as a mask, so that the holes on the porous substrate 2 and in the porous substrate 2 are formed. There is a problem that it is difficult to obtain a columnar body 5b having a uniform cross-sectional shape and a desired length due to adhesion of an electrode material to the inner wall of 2a and expansion of holes due to etching of the porous substrate itself. Further, since the dielectric thin film 6 is formed by depositing a dielectric material having a dielectric constant of 100 or more on the surface of the first electrode 5 having a structure in which the columnar bodies 5b are forested, the height of the columnar bodies 5b is increased. When the height is increased, there is a difference in the thickness of the dielectric thin film 6 generated between the surface of the first electrode 5 where the source gas is easy to hit and the source gas is difficult to hit facing the flow of the source gas. It was easy. Thus, there are a plurality of problems in increasing the height of the columnar body 5b, which hinders the increase in capacity.

  The present invention focuses on the above points, and an object of the present invention is to provide a capacitor element having a thin and uniform thickness and a large area dielectric layer. It is another object of the present invention to provide a method for easily manufacturing a capacitor element having a thin and uniform thickness and a large area dielectric layer. Another object of the present invention is to provide a small and large capacity capacitor using the above capacitor element.

  In order to achieve the above object, a capacitor element according to the present invention includes: (1) a first electrode having a plurality of columnar electrodes made of a first valve metal and an extraction electrode connected to one end of each of the plurality of columnar electrodes; A first electrode made of a valve metal; a dielectric layer made of an oxide film of the first valve metal formed at least near the surface of the first columnar electrode; and the plurality of columnar electrodes covering the surface of the dielectric layer And a second electrode filled in the gap. (... hereinafter referred to as first problem solving means)

  The main embodiments of the present invention are as follows: (2) The capacitor element is formed on a base, and the base is made of an oxide of a second valve metal and is perpendicular or substantially perpendicular to the upper surface. It has a honeycomb structure in which a plurality of holes are formed in the direction, and the columnar electrode of the first electrode is formed on a non-opening portion of the substrate of the honeycomb structure. (... hereinafter referred to as second problem solving means)

  The method for manufacturing a capacitor element according to the present invention includes (3) a step of anodizing a second valve metal film to form an anodized film having a honeycomb structure, and a first valve on the anodized film. Forming a metal film; etching a grain boundary of the first valve metal film to form a first electrode having an extraction electrode and a plurality of columnar electrodes on the extraction electrode; Oxidizing at least the surface of the plurality of columnar electrodes of one electrode and the surface of the extraction electrode to form a dielectric layer made of the oxide of the first valve metal; and covering the surface of the dielectric layer; And a step of forming a second electrode so as to fill a gap between the plurality of columnar electrodes. (... hereinafter referred to as third problem solving means)

The capacitor of the present invention includes (4) the capacitor element described in (1) above, a first terminal portion connected to the first electrode of the capacitor element, and a second terminal portion connected to the second electrode of the element. And an exterior material that covers the capacitor element except for a part of each of the first terminal portion and the second terminal portion. (... hereinafter referred to as fourth problem solving means)

Further, the main embodiment of the present invention is that (5) the exterior member has a rectangular parallelepiped shape, and the terminal portion is exposed in the vicinity of each of a pair of opposite sides of the bottom surface of the exterior member. It is characterized by being arranged. (... Hereinafter referred to as fifth problem solving means.)

In another main embodiment of the present invention, (6) a plurality of capacitor elements are provided, and a first electrode of the plurality of capacitor elements is provided at the first terminal portion and a second of the plurality of capacitor elements. The electrodes are respectively connected in parallel to the second terminal portions. (... Hereinafter referred to as sixth problem solving means)

The operation of the first problem solving means is as follows. That is, a first electrode made of a first valve metal having a plurality of columnar electrodes made of a first valve metal and an extraction electrode connected to one end of each of the plurality of columnar electrodes, and at least the first columnar electrode A dielectric layer made of an oxide film of the first valve metal and a second electrode that covers the surface of the dielectric layer and fills the gaps between the plurality of columnar electrodes. A thin and uniform dielectric layer can be disposed between the first electrode and the second electrode of the element. Further, the opposing area can be enlarged by increasing the length of the columnar electrode of the capacitor element.

The operation of the second problem solving means is as follows. That is, the capacitor element is formed on a base, and the base is made of an oxide of the second valve metal and has a plurality of holes formed perpendicularly or substantially perpendicularly to the upper surface. Since the columnar electrode of the first electrode is formed on the non-opening portion of the substrate of the honeycomb structure, a columnar electrode having a large length can be easily formed. A large-capacity capacitor element can be easily provided.

The operation of the third problem solving means is as follows. That is, a step of anodizing the second valve metal film to form an anodized film having a honeycomb structure, a step of forming a first valve metal film on the anodized film, and the first Etching a grain boundary of the valve metal film to form a first electrode having an extraction electrode and a plurality of columnar electrodes on the extraction electrode; and at least surfaces of the plurality of columnar electrodes of the first electrode; Oxidizing the surface of the extraction electrode to form a dielectric layer made of the oxide of the first valve metal; and covering the surface of the dielectric layer and filling the gaps between the plurality of columnar electrodes And forming the second electrode, a thin and uniform dielectric layer can be easily formed on the surface of the columnar electrode, and a large-capacity capacitor element can be easily manufactured.

  The operation of the fourth problem solving means is as follows. That is, the capacitor element according to (1) above, a first terminal portion connected to the first electrode of the capacitor element, a second terminal portion connected to the second electrode of the element, and the first terminal portion And a packaging material that covers the capacitor element except for each part of the second terminal portion, so that a short circuit between the first electrode and the second electrode can be effectively prevented, and the capacitor has excellent durability. Can be provided.

  The operation of the fifth problem solving means is as follows. That is, the exterior material has a rectangular parallelepiped outer shape, and the terminal portions are disposed in the vicinity of a pair of opposite sides of the bottom surface of the exterior material, so that the mountability is good. Can be provided.

  The operation of the sixth problem solving means is as follows. That is, a plurality of the capacitor elements are provided, the first electrodes of the plurality of capacitor elements are connected in parallel to the first terminal portion, and the second electrodes of the plurality of capacitor elements are connected in parallel to the second terminal portion, respectively. Therefore, a capacitor with a small mounting area and a large capacity can be provided.

The above and other objects, features, and advantages of the present invention will be apparent from the following detailed description and the accompanying drawings.

  ADVANTAGE OF THE INVENTION According to this invention, a small and high capacity | capacitance capacitor element can be provided. In addition, according to the present invention, it is possible to provide a capacitor having a small and large capacity capacitor element. Further, according to the present invention, a small and large capacity capacitor element can be easily manufactured.

  Next, a first embodiment of the capacitor element of the present invention will be described with reference to FIG. FIG. 1 is an enlarged cross-sectional view for explaining the internal structure of the capacitor element 10 of the first embodiment.

  As shown in FIG. 1, the capacitor element 10 according to the first embodiment is filled between the first electrode 15 having a plurality of columnar electrodes 15b and a plurality of columnar electrodes 15b like a sword mountain used for flower arrangement, for example. The second electrode 17 has a structure facing the dielectric layer 16. Specifically, the first electrode 15 includes a plurality of columnar electrodes 15b made of a first valve metal, and an extraction electrode 15a connected to one end of each of the plurality of columnar electrodes 15b. Made of metal. The dielectric layer 16 is formed at least near the surface of the columnar first electrode 15b and is made of an oxide film of the valve metal. The second electrode 17 covers the surface of the dielectric layer 16 and fills the gaps between the plurality of columnar electrodes 15b.

  Next, a first embodiment of a method for manufacturing a capacitor element of the present invention will be described with reference to FIGS. FIG. 2 is an enlarged cross-sectional view showing the first half of an example of the method for manufacturing a capacitor element of the present embodiment. FIG. 3 is a cross-sectional view showing an anodizing process as an example of the manufacturing method of the embodiment, and FIG. 4 is a cross-sectional view showing an anodizing process as an example of the manufacturing method of the embodiment. FIG. 5 is an enlarged cross-sectional view showing the second half of the example of the manufacturing method of the embodiment.

As a manufacturing method of the capacitor element of this embodiment, each cross section shown in the thickness direction is shown in FIG. First, as shown in FIG. 2 (A), the second valve metal film 11 is immersed in the anodizing treatment tank 27a as shown in FIG. 3, and the honeycomb structure as shown in FIG. 2 (B). A substrate 12 made of an anodic oxide film having the following is formed. Next, as shown in FIG. 2C, a first valve metal film 13 is formed on the substrate 12. Next, as shown in FIG. 2 (D), the grain boundary 13a of the first valve metal film 13 is etched, and a plurality of columnar electrodes whose one ends are connected to the extraction electrode 15a and the extraction electrode 15a, respectively. The first electrode 15 having 15b is formed. Next, as shown in FIG. 4, it is immersed in an anodic oxidation treatment tank 27a, and as shown in FIG. 5E, the surface of at least the plurality of columnar electrodes 15b of the first electrode 15 and the surface of the extraction electrode 15a. Is oxidized to form a dielectric layer 16 made of the oxide of the first valve metal. Next, as shown in FIG. 5 (AF), the second electrode 17 is formed so as to cover the surface of the dielectric layer 16 and fill the gaps between the plurality of columnar electrodes 15b. If necessary, it may have a step of removing the substrate 12 as shown in FIG.

Next, a preferred embodiment of the first valve metal is as follows. That is, examples of the first valve metal include Al, Ta, Nb, Ti, Hf, Zr, Zn, W, Bi, and Sb, or alloys thereof.

Next, a preferred embodiment of the first electrode 15 is as follows. In other words, the first electrode 15 only needs to have an extraction electrode 15a and a plurality of columnar electrodes 15b each having one end connected to the extraction electrode 15a. As for the arrangement of the plurality of columnar electrodes 15b in the first electrode 15, it is most suitable for increasing the capacity in terms of space efficiency that the columnar electrodes 15b are positioned at the vertices of an equilateral triangle. For example, it may be arranged such that the plurality of columnar electrodes 15b are respectively positioned at the vertices of a square.

Next, a preferred embodiment of the columnar electrode 15b is as follows. In other words, the columnar electrode 15b may be any one that is formed on the first extraction electrode 15a so as to protrude in a plurality of directions perpendicular or substantially perpendicular to the extraction electrode 15a. The diameter of the columnar electrode 15b may be several nm to several hundred nm. The height of the columnar electrode 15b is not particularly limited, but may be several nm to several μm, and more preferably several tens nm to several μm. The columnar electrode 15b is preferably a rod having a circular, elliptical, or polygonal cross-sectional shape orthogonal to the axis, but is not limited to this, and the cross-sectional shape orthogonal to the axis is not limited to this. For example, the capacity of the capacitor may be increased by forming a concave polygon such as a star shape or a U shape, or a ring shape. Further, the columnar electrode 15b is not limited to a rod shape, and may be a spiral spiral shape, for example.

Next, a preferred embodiment of a method for forming the columnar electrode 15b is as follows. That is, in the first method for forming the columnar electrode 15b, the first valve metal (for example, Al) used as the columnar electrode material is sputtered on the anodic oxide film of the second valve metal having a honeycomb structure. A film of several hundred nm to several μm is formed. At this time, the honeycomb pattern of the anodic oxide film of the second valve metal is transferred to the obtained first valve metal film 13, and grain boundaries along the thickness direction of the first valve metal film 13 are transferred. 13a is formed. The obtained first valve metal film 13 is etched along the grain boundaries 13a to form columnar shapes on the non-opening portions 12b of the substrate 12 made of the second valve metal anodized film of the honeycomb structure. Electrode 15b is formed. According to this, it is possible to obtain a plurality of columnar electrodes 15b made of the first valve metal aligned in the vertical or substantially vertical direction on the base 12 made of the anodic oxide film of the second valve metal. Most suitable for large capacity. At this time, by adjusting the etching depth, each of the plurality of columnar electrodes 15b is connected to one end of each of the plurality of columnar electrodes 15b at a portion in contact with the base 12 made of the anodic oxide film of the second valve metal of the honeycomb structure. It is preferable to leave a film-like portion to be the extraction electrode 15a. In the second method for forming the columnar electrode 15b, an alloy of a first valve metal (for example, Al) and Si is sputtered. At this time, the first valve metal and the Si undergo phase separation, and a plurality of the first valve metals are deposited in a columnar shape with a length of several tens to several hundreds of nanometers in the Si base material. The columnar electrode 15b made of the first valve metal is formed by selectively removing the Si base material from the obtained film by etching. According to this, it is possible to easily obtain a plurality of columnar electrodes 15b having the same orientation as described above. The third method for forming the columnar electrode 15b is to add impurities to the first valve metal (for example, Al) film, or to apply external stress to the first valve metal film, thereby forming the surface of the film. A plurality of whiskers made of a single crystal of the first valve metal and having a diameter of several hundred nm and a length of several μm are formed and can be used as the columnar electrode 15b. According to this, the columnar electrode 15b having a single crystal and good conductivity can be formed relatively easily. A fourth method for forming the columnar electrode 15b is to form a first valve metal (for example, Al) by CVD or plating under a predetermined film formation condition, so that a large number of columnar electrodes made of the first valve metal are formed. 15b is formed. According to this, many columnar electrodes 15b can be formed with high density, which is suitable for increasing the capacity of a capacitor. A fifth method for forming the columnar electrode 15b is to heat-treat a eutectic alloy of a first valve metal (for example, Al) and another metal under a predetermined condition, so that the first valve is formed in the eutectic alloy. A plurality of columnar electrodes made of metal are formed. A plurality of columnar electrodes 15b made of the first valve metal are obtained by etching the eutectic alloy under predetermined conditions. As described above, according to the above-described plurality of methods for forming the columnar electrode 15b made of the first valve metal, the high-aspect-ratio columnar electrode 15b having a relatively uniform cross-sectional shape orthogonal to the axis and good straightness. Can be easily obtained. In the case where it is not necessary to make the height of the columnar electrode 15b so high, for example, as shown in the background art, holes that penetrate in the thickness direction at predetermined intervals are provided in the heat resistant substrate, and this is used as a mask. A plurality of columnar electrodes 15b made of the first valve metal may be formed by using the first valve metal so as to be stacked by sputtering or etching.

Next, a preferred embodiment of the extraction electrode 15a is as follows. That is, the extraction electrode 15a is preferably formed integrally with one end side of each of the plurality of columnar electrodes 15b using the same valve metal as the plurality of columnar electrodes 15b. However, the present invention is not limited thereto, and the extraction electrode 15a formed separately from the columnar electrode 15b and the plurality of columnar electrodes 15b may be joined. Further, the extraction electrode 15a may be formed by forming a conductive material different from the first valve metal so as to be in contact with the plurality of columnar electrodes 1b.

Next, a preferred embodiment of the dielectric layer 16 is as follows. That is, the dielectric layer 16 may be made of the first valve metal oxide film, and the first valve metal oxide film may be an anodic oxide film of the first valve metal. preferable. When Al is used as the first valve metal, for example, an Al ₂ O ₃ film can be obtained as the dielectric layer 16, and the dielectric constant of the dielectric layer 16 is about 10.

Next, a preferred embodiment of the second electrode 17 is as follows. That is, the second electrode 17 may be any electrode as long as it covers the surface of the dielectric layer 16 and fills the gaps between the plurality of columnar electrodes 15b, and has conductivity and corrosion resistance. Any metal or alloy may be used. Specifically, single metals such as Au, Ag, Cu, Ni, Al, or alloys thereof are preferable.

Next, a preferred embodiment of the second valve metal is as follows. That is, as the second valve metal, as with the first valve metal, Al, Ta, Nb, Ti, Hf, Zr, Zn, W, Bi, Sb, or an alloy thereof can be used. The second valve metal is preferably different from the first valve metal when the columnar electrode 15b is formed by etching the grain boundaries 13a of the first valve metal film 13. , May be the same.

Next, a preferred embodiment of the substrate 12 is as follows. That is, the substrate 12 preferably has a honeycomb structure obtained by anodizing the second valve metal film. The thickness of the substrate 12 is preferably 100 nm to 100 μm. In addition, the holes 12a in the base 12 are preferably arranged so that the adjacent holes 12a are arranged at the vertices of the equilateral triangle, but the invention is not limited to this. It may be.

Next, examples of the method for manufacturing the capacitor according to the first embodiment will be described with reference to FIGS. First, as shown in FIG. 2A, a film 11 made of Al is prepared as a second valve metal. Next, as shown in FIG. 3, a cathode (Pt) plate 27b is set in an anodizing treatment tank 27a in which an electrolytic solution 28 is stored, and connected to a DC power source 29, and the second valve metal film 11 is attached to the anodizing bath 27a. By supplying a direct current as the anode, the second valve metal film 11 is anodized, and a substrate 12 having a honeycomb structure having a large number of holes 12a at predetermined intervals as shown in FIG. 2B is obtained. . Next, Al is deposited as a first valve metal on one main surface side of the substrate 12 by sputtering. At this time, as shown in FIG. 2C, a grain boundary 13a is formed along a direction perpendicular or substantially perpendicular to the substrate 12, and the first boundary 12b is formed on the non-opening portion 12b of the substrate 12 of the underlying honeycomb structure. One valve metal grows in a columnar shape. Next, the first valve metal film 13 obtained above is etched so as to expand the grain boundary 13a and leave the bottom of the grain boundary 13a, as shown in FIG. A columnar electrode 15b made of the first valve metal and a film-shaped extraction electrode 15a connected to one end of each of the plurality of columnar electrodes 15b are formed on the non-opening portion 12b of the substrate 12 having the honeycomb structure. . Next, as shown in FIG. 4, the cathode (for example, Pt) plate 27b is set in the anodizing tank 27a in which the electrolytic solution 28 is stored in the same manner as described above, connected to the DC power source 29, and obtained as described above. By flowing a direct current with the structure 14 as an anode, the surface of the columnar electrode 15b and the exposed surface of the extraction electrode 15a are anodized to form the first valve metal as shown in FIG. A dielectric layer 16 made of an oxide film (Al ₂ O ₃ ) is formed. Next, an electrode material (for example, Al) is formed by CVD so as to cover the surface of the dielectric layer 16 and fill the gaps between the plurality of columnar electrodes 15b, as shown in FIG. 5 (F). The electrode 17 is formed, and the capacitor element 10 is obtained on the substrate 12 having a honeycomb structure made of the oxide of the second valve metal. Finally, the base 12 is removed from the capacitor element 10 by cutting or the like to obtain the capacitor element 10 of the present embodiment.

In the above embodiment, Al is used for each of the first valve metal and the second valve metal. However, the present invention is not limited to this, and any of the above valve metals can be appropriately selected and used.

Next, a second embodiment of the capacitor element of the present invention will be described with reference to FIG. FIG. 6 is an enlarged cross-sectional view for explaining the capacitor element 19 of the present embodiment.

As shown in FIG. 6, the capacitor element 19 of the present embodiment is formed on the substrate 12 as in the first embodiment. Further, in the capacitor element 10 of the previous embodiment, the base body 12 is removed. However, the capacitor element 19 of the present embodiment is a part or all of the honeycomb structure base body 12 made of the oxide of the second valve metal. Is different from the previous embodiment in that Specifically, the capacitor element 19 is formed on the base 12, and the base 12 is made of an oxide of the second valve metal and has a plurality of vertical or substantially vertical directions with respect to the upper surface. It has a honeycomb structure in which holes 12a are formed. The first electrode 15 is formed on the non-opening portion 12b of the substrate 12 having the honeycomb structure.

Next, a first embodiment of a capacitor using the capacitor element of the present invention will be described with reference to FIG. FIG. 7 is an enlarged cross-sectional view for explaining the internal structure of the capacitor 20 of the present embodiment.

As shown in FIG. 7, the capacitor 20 of this embodiment is provided with an outer packaging material and a pair of terminal portions for external connection to the capacitor element of the first embodiment. Specifically, the capacitor 20 has a first terminal portion 21 connected to the first electrode 15 of the capacitor element 10 and a second terminal portion 22 connected to the second electrode 17 of the element 10. Further, the capacitor 19 includes an exterior material 18 that covers the capacitor element 10 except for a part of each of the first terminal portion 21 and the second terminal portion 22.

Further, in the capacitor 20 of the present embodiment, the exterior material 18 has a rectangular parallelepiped shape, and the terminal portions 21 and 22 are exposed in the vicinity of a pair of opposite sides of the bottom surface of the exterior material 19. It is arranged.

Next, preferred embodiments of the first terminal portion 21 and the second terminal portion 22 are as follows. That is, the first terminal portion 21 and the second terminal portion 22 are preferably conductive metal plates, and the conductive metal is preferably Cu, phosphor bronze, various stainless steels, Ni42-Fe alloy, or the like. One end portion 21a of the first terminal portion 21 is connected to the first electrode 15, and one end portion 22b of the second terminal portion 22 is connected to the second electrode 17, respectively. It is preferable to be connected to the first electrode 15 using an adhesive or spot welding.

Next, a preferred embodiment of the exterior member 18 is as follows. That is, it is preferable that the outer covering material 18 covers the capacitor element 10 except for a part of the first terminal portion 21 and the second terminal portion 22. The exterior material 18 is preferably composed mainly of an epoxy resin or other insulating resin, and an inorganic filler or the like may be added if necessary. Further, the exterior member 18 preferably has a rectangular parallelepiped shape, and a portion 21b of the first terminal portion 21 and the first portion are disposed in the vicinity of a pair of opposite sides of the bottom surface of the exterior member 18. It is preferable that a portion 22b of the second terminal portion 22 is disposed so as to be exposed.

Next, a second embodiment of a capacitor using the capacitor element of the present invention will be described with reference to FIG. FIG. 8 is an enlarged cross-sectional view for explaining the internal structure of the capacitor 30 of the present embodiment.

As shown in FIG. 8, the capacitor 30 of the present embodiment is similar to the capacitor 20 of the first embodiment in that a capacitor element 10 ′, an exterior member 38, and a pair of terminal portions 31 for external connection, 32. The difference from the capacitor 20 of the first embodiment is that the length of the plurality of columnar electrodes 15b ′ and 15b of the capacitor element 10 ′ used in the capacitor 30 of the present embodiment is the same as that of the capacitor element 10 of the first embodiment. Longer than the columnar electrode 15. Further, in the capacitor 20 of the first embodiment, the plurality of columnar electrodes of the capacitor element 10 are provided perpendicularly or substantially perpendicularly to the bottom surface of the exterior member 18, but the capacitor 30 of the present embodiment. , The plurality of columnar electrodes 15 b ′ of the capacitor element 10 ′ are provided in parallel or substantially in parallel with the bottom surface of the exterior member 38. In addition, a first terminal portion 31 having one end 31a connected to the first electrode 15 'and a second terminal portion 32 having one end 32a connected to the second electrode 17' are each the exterior material 38. The part 31b of the first terminal part 31 and the part 32b of the second terminal part 32 are respectively in the vicinity of a pair of opposite sides of the bottom face of the exterior member. It is arranged so as to be exposed. In the capacitor 30 of this embodiment, the opposing area can be enlarged by increasing the length of the columnar electrode 15b ″ compared to the capacitor 120 of the first embodiment, and a small and large-capacitance capacitor can be obtained. Can be provided.

Next, a third embodiment of the capacitor of the present invention will be described with reference to FIG. FIG. 9 is an enlarged cross-sectional view for explaining the internal structure of the capacitor 940 of the present embodiment.

As shown in FIG. 9, the capacitor 40 of this embodiment includes a plurality of capacitor elements 10. Specifically, in the capacitor 40 of the present embodiment, the first electrodes 215 of the plurality of capacitor elements 10 are respectively parallel to the first terminal portions 41, and the second electrodes 2217 of the plurality of capacitor elements 10 are Each of the second terminal portions 42 is connected in parallel.

Further, in the capacitor 40 of this embodiment, like the capacitors of the first and second embodiments, the exterior material 48 has a rectangular parallelepiped shape, and a pair of opposed bottom surfaces of the exterior material 48 are opposed to each other. The terminal portions 41 and 42 are disposed so as to be exposed in the vicinity of each of the sides.

  According to the present invention, it is suitable for various light, thin, and short electronic devices using small and large-capacity capacitors.

It is an expanded sectional view showing an internal structure of a 1st embodiment of a capacitor element of the present invention. It is an expanded sectional view showing a 1st embodiment of a manufacturing method of a capacitor element of the present invention. It is an expanded sectional view showing the manufacturing method of the 1st embodiment. It is an expanded sectional view showing the manufacturing method of the 1st embodiment. It is an expanded sectional view showing the manufacturing method of the 1st embodiment. It is an expanded sectional view which shows the internal structure of 2nd Embodiment of the capacitor | condenser element of this invention. It is an expanded sectional view showing an internal structure of a 1st embodiment of a capacitor of the present invention. It is an expanded sectional view which shows the internal structure of 2nd Embodiment of the capacitor | condenser of this invention. It is an expanded sectional view which shows the internal structure of 3rd Embodiment of the capacitor | condenser of this invention. It is a figure which shows background art. It is sectional drawing which shows background art. It is sectional drawing which shows background art.

Explanation of symbols

10, 10 ′: Capacitor element 11: Second valve metal film 12: Substrate (second valve metal anodized film)
12a: Hole 12b: Non-opening portion 13: First valve metal film 13a: Grain boundary 15, 15 ′: First electrode 15a, 15a ′: Extraction electrode 15b, 15b ′: Columnar electrode 16, 16 ′: Dielectric Layer (anodized film of first valve metal)
17, 17 ': Second electrode (embedded electrode)
18: Exterior material 20: Capacitor 21: Terminal part 22: Terminal part 27a: Anodizing tank 27b: Cathode (Pr)
28: Electrolytic solution 29: Power source 30: Capacitor 31: Terminal part 32: Terminal part 38: Exterior material 40: Capacitor 41: Terminal part 42: Terminal part 48: Exterior material

Claims (6)

A first electrode made of a first valve metal having a plurality of columnar electrodes made of the first valve metal and an extraction electrode connected to one end of each of the plurality of columnar electrodes, and at least the surface of the first columnar electrode A dielectric layer formed in the vicinity of the oxide film of the first valve metal; and a second electrode that covers the surface of the dielectric layer and is filled in gaps between the plurality of columnar electrodes. Capacitor element. The capacitor element is formed on a base body, and the base body is made of a second valve metal oxide and has a honeycomb structure in which a plurality of holes are formed in a direction perpendicular to or substantially perpendicular to the upper surface. 2. The capacitor element according to claim 1, wherein the columnar electrode of the first electrode is formed on a non-opening portion of the substrate having the honeycomb structure. Forming a anodic oxide film having a honeycomb structure by anodizing a second valve metal film; forming a first valve metal film on the anodic oxide film; and Etching a grain boundary of the film to form a first electrode having an extraction electrode and a plurality of columnar electrodes on the extraction electrode; and at least surfaces of the plurality of columnar electrodes of the first electrode and the extraction electrode Forming a dielectric layer made of an oxide of the first valve metal, and covering the surface of the dielectric layer and filling gaps between the plurality of columnar electrodes. And a step of forming an electrode. 2. The capacitor element according to claim 1, a first terminal portion connected to a first electrode of the capacitor element, a second terminal portion connected to a second electrode of the element, the first terminal portion and the second terminal portion. And a packaging material that covers the capacitor element except for a part of each terminal portion. The said exterior material has a rectangular parallelepiped external shape, It arrange | positions so that the said terminal part may be exposed in the vicinity of each of a pair of mutually opposing side of the bottom face of this exterior material. Capacitor. A plurality of the capacitor elements are provided, the first electrodes of the plurality of capacitor elements are connected in parallel to the first terminal portion, and the second electrodes of the plurality of capacitor elements are connected in parallel to the second terminal portion, respectively. The capacitor according to claim 4.

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