[DESCRIPTION]
[Invention Title]
METAL CAPACITOR AND MANUFACTURING METHOD THEREOF [Technical Field] The present invention relates to a metal capacitor and a manufacturing method thereof, and more particularly, to a metal capacitor in which an electric conductivity is significantly improved by applying a metal material for an electrolyte and a manufacturing method thereof.
[Background Art] An aluminum electrolytic capacitor is used to smooth a power output from a power circuit to be a predetermined value, or is used as a low frequency bypass. Hereinafter, a method of manufacturing the aluminum electrolytic capacitor will be briefly described.
An etching process of etching the surface of an aluminum foil is performed to enlarge a surface area of the aluminum foil and thereby increase an electric capacity. When the etching process is completed, a forming process of forming a dielectric substance on the aluminum foil is performed. When cathode and anode aluminum foils are manufactured through the etching process and the forming process, a slitting process of cutting the manufactured aluminum foil and a separator by as long as a desired width based on the length of a product is performed. When the slitting process is completed, a stitching process of stitching an aluminum lead patch, which is a lead terminal, to the aluminum foil is performed.
When the slitting of the aluminum foil and the separator is completed, a winding process of disposing the separator between the anode aluminum foil and the cathode aluminum foil, and then winding the separator and the aluminum foils in a cylindrical shape and attaching a tape thereto, so as to not be unwounded. When the winding process is completed, an impregnation process of inserting the wound device into an aluminum case and injecting an electrolyte is performed. When the injecting of the electrolyte is completed, a curing process of sealing the aluminum case using a sealing material is performed. When the curling process is completed, an aging process of restoring a damage to the dielectric substance is performed. Through this, the assembly of the aluminum electrolytic capacitor is completed. Due to advancement in digitalization and slimness of current electronic devices, there is a need for a capacitor having a low impedance in a high frequency. In order to improve the conventional aluminum electrolytic capacitor manufactured as above, a functional layer-type aluminum solid capacitor or a functional tantalum capacitor is used, However, there are problems as follow.
Since the conventional functional layer-type aluminum solid capacitor or the functional tantalum capacitor uses conductive polymer compounds such as polypyrrole or polythiophene, for electrolyte, there are some constraints on the thermal resistance and the withstanding voltage. Also, since a negative electrode is formed by spraying paste such as graphite in turn, the capacitor becomes thicker. Accordingly, there is some constraint on the number of layers and a contact resistance occurs between layers to thereby deteriorate the impedance. [Disclosure] [Technical Problem]
The present invention is conceived to solve the above-described problems and thus provides a metal capacitor in which an electric conductivity is improved by about 10,000 to 1,000,000 folds by applying a metal material for an electrolyte, in comparison to when using a conventional electrolyte or an organic semiconductor, a multi-layer metal capacitor using the metal capacitor, and a manufacturing method thereof.
The present invention also provides a metal capacitor which can improve a thinness, a low equivalent series resistance (ESR), a reduction in a ripple pyrexia, a long life, a heat-resistant stability, non-fuming, non-firing, and environment by using a metal material for an electrolyte, and a manufacturing method thereof.
[Technical Solution] According to an aspect of the present invention, there is provided: a metal capacitor including: a terminal increase-type metal member including a groove forming portion where a plurality of grooves is arranged, and first and second electrode withdrawing portions formed on the groove forming portion; a metal oxide film being formed on the terminal increase-type metal member; a plurality of seed electrode layers being formed on the metal oxide films that are formed on both surfaces of the groove forming portion of the terminal increase-type metal member; a plurality of main electrode layers being formed on the plurality of seed electrode layers formed in the groove forming portion to fill in the plurality of grooves formed on the groove forming portion of the terminal increase-type metal member; an insulating layer being formed on the plurality of main electrode layers and the terminal increase-type metal member to externally expose the first and the second electrode withdrawing portions of the terminal increase-type metal member; a plurality of conductive connecting layers being formed on the plurality of main electrode layers and the insulating layer to make the first and the second electrode withdrawing portions of the metal member orthogonal to each other and connect the plurality of main electrode layers; a first lead terminal being selectively connected to the fist and the second electrode withdrawing portions of the terminal increase-type metal member; a second lead terminal being connected to the main electrode layer of the terminal increase-type metal member; and a sealing member sealing the terminal increase-type metal member connected to the first and the second lead terminals to externally expose the first and the second lead terminals.
According to another aspect of the present invention, there is provided a method of forming a metal capacitor, including: forming a groove forming portion that includes a plurality of grooves on both surfaces to thereby form a terminal increase-type metal member integrally formed with fist and second electrode withdrawing portions by using a direct current (DC) etching scheme; forming a metal oxide film on the terminal increase-type metal member by using an anodizing scheme, when the groove forming portion, and the first and the second electrode withdrawing portions are integrally formed on the terminal increase-type metal member; forming a plurality of seed electrode layers on the metal oxide layer formed in the groove forming portion to be penetrated into the metal oxide layer by using an electroless plating or an electroplating, when the metal oxide film is formed; forming a plurality of main electrode layers to fill in the plurality of grooves formed on the groove forming portion of the metal member by using the plurality of seed electrode layers as media, when the plurality of seed electrode layers is formed; forming an insulating layer on the plurality of main electrode layers and the terminal increase-type metal member to externally expose the first and the second electrode withdrawing portions of the terminal increase-type metal member by using a chemical vapor deposition (CVD) scheme, when the plurality of main electrode layers is formed; forming a conductive connecting layer on the plurality of main electrode layers and the insulating layer to make the first and the second electrode withdrawing portions of the terminal increase-type metal member orthogonal to each other and connect the plurality of main electrode layers, when the insulating layer is formed; connecting the first lead terminal to the main electrode layer of the terminal increase-type metal member and connecting the second lead terminals to the first and the second electrode withdrawing portions of the metal member, when the conductive connecting layer is formed; and sealing the terminal increase-type metal member with a sealing member to externally expose the first and the second lead terminals, when the first and the second lead terminals are connected. [Advantageous Effects] According to the present invention, it is possible to improve an electric conductivity by about 10,000 to 1 ,000,000 folds by applying a metal material for an electrolyte, in comparison to when using a conventional electrolyte or an organic semiconductor, Also, since the serial multi-laying is possible, high- voltage is enabled. Also, since the polarity has no directivity, a relatively higher safety is provided. Also, it is possible to improve a thinness, a low equivalent series resistance (ESR), a reduction in a ripple pyrexia, a long life, a heat-resistant stability, non-fuming, non-firing, and environment. [Description of Drawings]
FIG. 1 is a perspective view of a metal capacitor according to a first embodiment of the present invention;
FIG. 2 is a cross-sectional view cut along A1-A2 line of the metal capacitor shown in FIG. 1;
FIG. 3 is a cross-sectional view cut along B1-B2 of the metal capacitor shown in FIG. 1 ; FIGS. 4A through 4h are cross-sectional views illustrating a method of manufacturing the metal capacitor according to the first embodiment of the present invention;
FIG. 5 is a cross-sectional view of a metal capacitor according to a second embodiment of the present invention; and FIG. 6 is a cross-sectional view of a metal capacitor according to a third embodiment of the present invention. [Best Mode]
(First embodiment)
Hereinafter, a configuration of a metal capacitor according to a first embodiment of the present invention will be described with reference to FIGS. 1 through 3.
FIG. 1 is a perspective view of a metal capacitor 10 according to the first embodiment of the present invention, FIG. 2 is a cross-sectional view cut along A1-A2 line of the metal capacitor shown in FIG. 1, and FIG. 3 is a cross- sectional view cut along B1-B2 of the metal capacitor shown in FIG. 1. As shown in the figures, the metal capacitor 10 according to the first embodiment of the present invention includes a terminal increase-type metal member 11, a metal oxide film 12, a plurality of seed electrode layers 13, a plurality of main electrode layers 14, an insulating layer 15, a plurality of conductive conducting layers 16, a first lead terminal 21, a second lead terminal 22, and a sealing member 30. Hereinafter, the configuration thereof will be sequentially described.
As shown in FIG. 4B, the terminal increase-type metal member 11 includes a groove forming portion 11a that is provided by arranging a plurality of grooves Hd on its both surfaces, and first and second electrode withdrawing portions l ib and l ie formed on one end and another end of the groove forming portion 11a. The terminal increase-type metal member 11 may connect three terminal electrodes by increasing a number of terminals. Each of a plurality of grooves Hd that is formed in the groove forming portion 11a is formed in the shape of a circle or a polygon. The terminal increase- type metal member 11 where the groove forming portion 11a, and the electrode withdrawing portion lib and lie are integrally formed uses any one of aluminum (Al), niobium (Nb), tantalum (Ta), titanium (Ti), and zirconium (Zr). The metal oxide film 12 is formed on the terminal increase-type metal member 11, and uses any one of alumina(Al2θ3), oxide niobium(Nb2θδ), monoxide niobium (NbO), oxide tantalum(Ta2θδ), oxide titanium (TiU2) , and oxide zirconium(Zrθ2). The metal oxide film 12 is formed on both surface (top and bottom) and a side l ie of the terminal increase-type metal member 11.
The plurality of seed electrode layers 13 is formed on the metal oxide film 12 that are formed on both surfaces of the groove forming portion 11a of the terminal increase-type metal member 11. The plurality of main electrode layers 14 is formed on the plurality of seed electrode layers formed on both surfaces of the groove forming portion 11a to fill in the plurality of grooves Hd formed on the groove forming portion 11a of the terminal increase-type metal member 11.
The insulating layer 15 is formed on the terminal increase-type metal member 11 and the plurality of main electrode layers 14 along the side l ie of the terminal increase-type metal member 11 so that the first and the second electrode withdrawing portion l ib and l ie of the terminal increase-type metal member 11 may be externally exposed. The insulating layer 15 is formed on all the remaining side l ie of the terminal increase-type metal member 11 , excluding the surface where the first and the second electrode withdrawing portions l ib and l ie of the terminal increase-type metal member 11 is formed.
The plurality of conductive connecting layers 16 is formed on the plurality of main electrode layers 14 and the insulating layer 15 to make the first and the second electrode withdrawing portion l ib and l ie of the terminal increase-type metal member 11 orthogonal to each other and connect the plurality of main electrode layers 14. In order to connect the plurality of main electrode layers 14, the plurality of conductive connecting layers 16 is formed on the plurality of main electrode layers 14 and the insulating layer 15 to make the first and the second electrode withdrawing portions Hb and l ie orthogonal to each other. The first and the second electrode withdrawing portions l ib and l ie face each other. Each of the plurality of main electrode layers 14 that is electrically connected by the conductive connecting layer 16, the seed electrode layer 13, and the conductive connecting layer 16 uses any one of aluminum (Al), copper (Cu), zinc (Zn), silver (Ag), nickel (Ni), tin (Sn), indium (In), palladium (Pd), platinum (Pt), cobalt (Co), ruthenium (Ru), and gold (Au).
The first lead terminal 21 is selectively connected to the first and the second electrode withdrawing portions l ib and Hc of the terminal increase- type metal member 11. For example, the first lead terminal 21 may be connected to the first electrode withdrawing portion l ib of the terminal increase-type metal member 11 or to the second electrode withdrawing portion l ie of the terminal increase-type metal member 11. The second lead terminal is connected to the main electrode layer 14 of the terminal increase- type metal member 11. Through this, the non-polar metal capacitor 10 is constructed.
In order to improve the adhesiveness of the second lead terminal 22 connected to one of the main electrode layers 14, a conductive adhesive layer 17 is further provided. The conductive adhesive layer 17 is formed on the main electrode layer 14 connected to the second lead terminal 22 among the plurality of main electrode layers 14. The sealing member 30 seals the terminal increase-type metal member 11 connected to the first and the second lead terminals 21 and 22, so that the first and the second lead terminals 21 and 22 may be externally exposed. The sealing member 30 uses molding material or a cover member with an empty inside.
Hereinafter, a manufacturing method of the metal capacitor 10 according to the first embodiment will be described with reference to the accompanying drawings. As shown in FIG. 4A, when a member 1 such as film, foil, etc., of a metal material is provided, the manufacturing method of the metal capacitor 10 according to the first embodiment of the present invention forms the groove forming portion Ha where the plurality of grooves Hd is arranged on both surfaces of the member 1 and thereby forms the terminal increase-type metal member 11 integrally formed with the first and the second electrode withdrawing portion Hb and l ie on one end and the other end of the groove forming portion l la. The first and the second electrode withdrawing portions l ib and l ie formed on the terminal increase-type metal member 11 are constructed to make the metal capacitor have three terminals when constructing a polar metal capacitor by selectively connecting the second lead terminal 22, and may be constructed to make the metal capacitor have two terminals even when the metal capacitor is non-polar. The plurality of grooves l id formed on the groove forming portion Ha of the terminal increase-type metal member 11 is formed in the shape of a circle or a polygon and has a diameter of about lnm through 100 μm. When the thickness of the terminal increase-type metal member 11 is 1 μm, the depth of the metal member 11 is formed to be less than about 0.5 μm. For example, when the thickness of the metal member 11 is 300 μm, the depth of the metal member 11 is formed to be less than 150 μm. As shown in FIG. 4C, when the groove forming portion l la, and the first and the second electrode withdrawing portions l ib and l ie are integrally formed on the terminal increase-type metal member 11 , the manufacturing method performs a forming process of forming the metal oxide film 12 on the terminal increase-type metal member 11 by using an anodizing scheme. As shown in FIG. 4D, when the metal oxide film 12 is formed, the manufacturing method forms the plurality of seed electrode layers on the metal oxide film 12 that is formed in the groove forming portion 11a to be penetrated into the metal oxide film 12 by using an electroless plating or an electroplating. As shown in FIG. 4E, when the plurality of seed electrode layers 13 is formed, the manufacturing method forms the plurality of main electrode layers 14 to fill in the plurality of grooves Hd formed in the groove forming portion 11a of the terminal increase-type metal member 11 by using the plurality of seed electrode layers 13 as media, by using the electroless plating or the electroplating. As shown in FIG. 4F, when the plurality of main electrode layers 14 is formed, the manufacturing method forms a non-through type metal member 10a by forming the insulating layer 15 on the plurality of main electrode layers 14 and the side l ie of the terminal increase-type metal member 11 along the side l ie of the terminal increase-type metal member 11 by using a CVD scheme, so that the first and the second electrode withdrawing portion l ib and l ie of the terminal increase-type metal member 11 may be externally exposed. The insulating layer 15 is formed using an insulating tape or a resin material. As shown in FIG. 4G, when the insulating layer 15 is formed, the manufacturing method forms a conductive connecting layer 16, connecting the plurality of main electrode layers 14, on the side l ie of terminal increase-type metal member 11 in a direction where the first and the second electrode withdrawing portions l ib and Hc of the terminal increase-type metal member 11 are orthogonal to each other.
As shown in FIG. 3, when the conductive connecting layer 16 is formed, the manufacturing method connects the first lead terminal 21 to the main electrode layers 14 of the terminal increase-type metal member 11 and selectively connects the second lead terminal 22 to the first and the second electrode withdrawing portions l ib and l ie. For example, when constructing the polar metal capacitor by selectively connecting the second lead terminal 22 to the first and the second electrode withdrawing portions Hb and l ie, it is possible to construct the metal capacitor to have three terminals. Also, when constructing the non-polar metal capacitor, it is possible to construct the metal capacitor to have two terminals.
Between the forming of the conductive connecting layer 16 and the connecting of the first and the second lead terminals 21 and 22, the manufacturing method forms the conductive adhesive layer 17 on the main electrode layer 14 connected to the second lead terminal 22 in order to improve the adhesivenss of the first and the second lead terminals 21 and 22. The conductive adhesive layer 17 is formed by using any one of a scheme of spraying metal adhesives or solder paste, the electroplating, and the electroless plating.
As shown in FIG. 3, when the first and the second lead terminals 21 and 22 are connected, the manufacturing method seals the terminal increase-type metal member 11 with the sealing member 30 so that the first and the second lead terminals 21 and 22 may be externally exposed. When sealing the terminal increase-type metal member 11 with the sealing member 30, the terminal increase-type metal member 11 is sealed using molding material or a cover member with an empty inside. (Embodiment 2) A metal capacitor 110 using the non-through type metal member 10a constituting the metal capacitor 10 according to the first embodiment of the present invention will be described with reference to the accompanying drawing.
As shown in FIG. 5, the metal capacitor 110 according to the second embodiment of the present invention includes a plurality of non-through type metal members 10a, a conductive adhesive layer 17, a third lead terminal 23, a fourth lead terminal 24, and a sealing member 30. Hereinafter, the configuration thereof will be sequentially described.
Each of the plurality of non-through type metal members 10a includes the terminal increase-type metal member 11, the metal oxide film 12, the plurality of seed electrode layers 13, the plurality of main electrode layers 14, the insulating layer 15, and the conductive connecting layer 16. The configuration thereof has been described above when describing the metal capacitor 10, and thus further detailed descriptions will be omitted here. The plurality of non-through type metal members 10a is sequentially disposed. The conductive adhesive layer 17 is disposed between the main electrode layers 14 of the plurality of non-through type metal members 10a and thereby adheres the plurality of non-through type metal members 10a.
The third lead terminal 23 is connected to the first electrode withdrawing portions Hb of the non-through type metal members 10a that are located in odd number* locations among the plurality of disposed non-through type metal members 10a. Specifically, as shown in FIG. 5, when it is assumed that, among the plurality of disposed non-through type metal members 10a, an uppermost located non-through type metal members 10a is a first non-through type metal member 10a and non-through type metal members 10a located therebelow is a second non-through type metal member 10a, the third lead terminal 23 is connected to the first electrode withdrawing portions l ib of the non-through type metal members 10a located in the odd number* locations such as the first or the third location. Conversely, the fourth terminal 24 is connected to the second electrode withdrawing portions l ie of non-through type metal members 10a that are located in even numberth locations among the plurality of disposed non-through type metal members. Through this, the non-polar metal capacitor 110 is constructed. Specifically, the third and the fourth lead terminals 23 and 24 are connected to the first and the second electrode withdrawing portions l ib and l ie of the terminal increase-type metal member 11 formed with the metal oxide film having the same polarity. Accordingly, the metal capacitor 110 is constructed to have the non-polarity.
The sealing member 30 seals the plurality of non-through type metal members 10a, connected with the third and the fourth lead terminals 23 and 24, so that the third and the fourth lead terminals 23 and 24 may be externally exposed. Through this, the non-polar metal capacitor 110 is constructed to thereby protect the plurality of internally disposed non-through type metal members 10a.
(Embodiment 3) A metal capacitor 120 using the non-through type metal member 10a constituting the metal capacitor 10 according to the first embodiment of the present invention will be described with reference to the accompanying drawing.
As shown in FIG. 6, the metal capacitor 120 according to the third embodiment of the present invention includes a plurality of non-through type metal members 10a, a conductive adhesive layer 17, a first polar lead terminal 25, a second polar lead terminal 26, and a third polar lead terminal 27. Hereinafter, the configuration thereof will be sequentially described.
Each of the plurality of non-through type metal members 10a includes the terminal increase-type metal member 11 , the metal oxide film 12, the plurality of seed electrode layers 13, the plurality of main electrode layers 14, the insulating layer 15, and the conductive connecting layer 16. The configuration thereof has been described above when describing the metal capacitor 10, and thus further detailed descriptions will be omitted here. The plurality of non-through type metal members 10a is sequentially disposed. The conductive adhesive layer 17 is disposed between the main electrode layers 14 of the plurality of non-through type metal members 10a and thereby adheres the plurality of non-through type metal members 10a.
The first polar lead terminal 25 is connected to the first electrode withdrawing portions l ib of the plurality of disposed non-through type metal members 10a and the second polar lead terminal 26 is connected to one of the main electrode layers 14 of the plurality of non-through type metal members 10a. As shown in FIG. 6, the second polar lead terminal 26 is connected to the lowest located main electrode layer 14 among the plurality of main electrode layers 14 of the plurality of non-through type metal members 10a. In order to improve the adhesiveness of the second polar lead terminal 26 connected to the main electrode layer 14, the conductive adhesive layer 17 is formed on one of the main electrode layers 14 of the plurality of non-through type metal members 10a. The third polar lead terminal 27 may be connected to the second electrode withdrawing portions l ie of the plurality of non-through type metal members 10a and thereby construct the metal capacitor 120 as three terminals. Among the first through third polar lead terminals consisting of three terminals, the first to the third lead terminals 25, 26 and 27 are connected to the first and the second electrode withdrawing portions l ib and l ie of the metal oxide film 12 to function as a positive electrode, and thus are used as an anode electrode. The second polar lead terminal 26 is connected to the main electrode layer 14 where the metal oxide film 12 is not formed, to function as a negative electrode, and thus is used as a cathode node. Through this, the metal capacitor is constructed to have a polarity.
The terminal increase-type metal member 11 including the first and the first electrode withdrawing portions l ib and l ie may be applicable to function as the negative electrode. When the metal member 11 functions as the negative electrode, the main electrode layer 14 functions as the positive electrode. Accordingly, when the second polar lead terminal 26 is applied to the cathode electrode, the first and the third polar lead terminal 25 and 27 are applied to the anode electrode. Conversely, when the second polar lead terminal 26 is applied to the anode electrode, the first and the third polar lead terminal 25 and 27 are applied to the cathode electrode. Also, when the first and the third polar lead terminal 25 and 27 are applied to the cathode electrode, the second polar lead terminal 26 is applied to the anode electrode. Conversely, when the first and the third polar lead terminal 25 and 27 are applied to the anode electrode, the second polar lead terminal 26 is applied to the cathode electrode. The sealing member 30 seals the plurality of non-through type metal members 10a, connected with the first through third polar lead terminals
25, 26, and 27, so that the first through third polar lead terminals 25, 26, and 27 may be externally exposed. Through this, it is possible to protect the plurality of internally disposed non-through type metal members 10a. As described above, since a non-through type metal capacitor according to the present invention uses a metal material, high voltage is enabled and also it is possible to improve the safety for thermal resistance and environmental influence. Accordingly, since it is not necessary to form a negative pole, the capacitor may be manufactured in slim. Also, since interlayer contact resistance does not occur, the impedance characteristic may be improved. [Industrial Applicability]
A metal capacitor according to the present invention may be applicable to a smoothing circuit of a power circuit, a noise filter, a bypass filter, and the like.