JP2006253412A - Solid electrolytic capacitor and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a solid electrolytic capacitor precisely lining up the end face of a capacitor element in a lamination direction by cutting a plurality of laminated capacitor elements to the lowest layer, and also to provide the solid electrolytic capacitor. <P>SOLUTION: In a laser cutting process in the manufacturing method of the solid electrolytic capacitor, four laminated capacitor elements 10-40 are cut from end edge sections 13-43 by laser scanning. In the laser cutting process, a slit 40a is formed at an edge 41B at a positive electrode section by laser scanning, a slit 30a that is narrower than the slit 40a is formed at an edge 31B of the positive electrode, a slit 20a that is narrower than the slit 30a is formed at an edge 21B of the positive electrode, and a slit 10a that is narrower than a slit 10a is formed at the edge 11B of the positive electrode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a solid electrolytic capacitor manufacturing method and a solid electrolytic capacitor, and more particularly, a solid electrolytic capacitor manufacturing method for stacking a plurality of capacitor elements and electrically connecting them in parallel to manufacture a solid electrolytic capacitor, and the manufacturing method. The present invention relates to a solid electrolytic capacitor.

As a solid electrolytic capacitor, a configuration in which a plurality of capacitor elements are stacked and electrically connected in parallel in order to ensure high capacitance has been conventionally known. For example, Japanese Patent Laid-Open No. 10-144573 (see Patent Document 1) describes a solid electrolytic capacitor having this configuration and a method for manufacturing the same. In the method of manufacturing a solid electrolytic capacitor, a plurality of plate-like capacitor elements constituting the solid electrolytic capacitor are punched out by a mold and formed into a predetermined shape, and then laminated to form a solid electrolytic capacitor.
Japanese Patent Laid-Open No. 10-144573

  However, in the above-described conventional method for manufacturing a solid electrolytic capacitor, since plate-shaped capacitor elements that have been punched out in advance with a predetermined shape are stacked, it is not possible to align the end faces of the capacitor elements in the stacking direction with high accuracy. It was difficult.

  As a manufacturing method different from the above-described conventional solid electrolytic capacitor manufacturing method, for example, after laminating a plurality of plate-like capacitor elements, laser irradiation is performed from above in the laminating direction of the laminated capacitor elements, thereby A method is conceivable in which the external shape is defined by simultaneously cutting the capacitor elements. When the outer shape of the solid electrolytic capacitor is defined by such a method, a plurality of plate-like capacitor elements can be simultaneously cut by laser irradiation, so that the cut surfaces that are the end faces of the cut capacitor elements can be aligned.

However, even when trying to cut a plurality of plate-like capacitor elements at the same time by laser irradiation from the upper side in the stacking direction of the capacitor elements, even if the upper layer can be cut, the lower layer cannot be cut simultaneously. . This is the same whether a YAG laser is used or a YVO ₄ laser that is stronger than YAG is used.

  Here, in a state where the upper capacitor element is cut and the lower capacitor element is not cut, an unnecessary portion of the cut upper capacitor element is removed, and then the lower capacitor element is irradiated with laser. It is conceivable that the capacitor elements in the lower layer are cut to remove unnecessary portions and cut and removed one by one. However, this makes it unnecessary to remove unnecessary portions and complicates the manufacturing process of the solid electrolytic capacitor. Moreover, when removing an unnecessary part, there exists a possibility that the part used as the anode part of a solid electrolytic capacitor may deform | transform.

  Therefore, the present invention provides a solid electrolytic capacitor manufacturing method and a solid electrolytic capacitor capable of cutting a plurality of stacked capacitor elements down to the lowest layer and aligning the end faces of the capacitor elements in the stacking direction with high accuracy. The purpose is to do.

  In order to achieve the above object, the present invention provides a method of manufacturing a solid electrolytic capacitor having a capacitor element manufacturing process, a laminating process, a laser cutting process, and a connecting process. The capacitor element manufacturing step includes a step of forming a cathode portion having a solid electrolyte layer in a predetermined region on the surface of an anode portion made of a valve metal having an oxide film layer formed on the surface. In the laminating process, a plurality of the capacitor elements manufactured by performing the capacitor element manufacturing process a plurality of times are arranged so that the ends of the anode parts are adjacent to each other, and the cathode parts are arranged in a stacked manner. To do.

  In the laser cutting step, a direction in which the portion of the anode portion in which the cathode portion is not formed protrudes from a portion in which the cathode portion is formed in a layered manner in the capacitor element, and a direction in which the capacitor elements are stacked Is the stacking direction, and the direction perpendicular to the stacking direction and the direction perpendicular to the stacking direction is the width direction, and the stacking direction extends from one end of the width direction to the other end of all the capacitor elements. A slit is formed by laser irradiation from above, and the edge of the anode portion located in the protruding direction is cut off from the slit. Further, in the laser cutting step, the width of the slit of the capacitor element other than the capacitor element arranged in the lowermost layer in the stacking direction is equal to the width of the slit of the capacitor element arranged in the lowermost layer in the stacking direction. The slits each having a width wider than the beam spot diameter of the laser are formed in the plurality of capacitor elements so as to be wider than the width. In the connecting step, the plurality of stacked capacitor elements are electrically connected in parallel to each other.

  In the laser cutting step, the width of the slit of the capacitor element other than the capacitor element arranged in the lowermost layer in the stacking direction is larger than the width of the slit of the capacitor element arranged in the lowermost layer in the stacking direction. Since the slits having a width wider than the beam spot diameter of the laser are formed in each of the plurality of capacitor elements so as to widen, the end portions of the anode portions of the plurality of stacked capacitor elements are cut by laser irradiation. Can be dropped. For this reason, each cut surface of the anode part produced by cutting off the edge part of the anode part by laser irradiation can be flush with each other in the stacking direction of the plurality of capacitor elements. For this reason, when the plate-shaped connecting member made of a conductive material is fixed across the end portions of all the anode portions and the anode portions are electrically connected to each other at the cut surface, The electrical connection with the end can be ensured. Moreover, the dimensional accuracy of the manufactured solid electrolytic capacitor can be improved, and the yield can be improved.

  In addition, it is not necessary to repeat the process of removing the anode part of the laminated capacitor element by laser irradiation and then removing the part of the cut anode part. Can be prevented from being deformed, and the manufacturing process can be simplified.

  Here, in the laser cutting step, it is preferable that the capacitor element arranged in the lower layer in the stacking direction is formed with the narrower slit than the capacitor element arranged in the upper layer in the stacking direction.

  The capacitor element arranged in the lower layer in the stacking direction is formed with a narrower slit than the capacitor element arranged in the upper layer in the stacking direction, so that a desired width is formed at the end of the anode part of the capacitor element in the lower layer. Slits can be formed.

  Further, the connecting step includes connecting the end portions of the anode portions of the plurality of capacitor elements to the cut surface of the anode portions generated by cutting off the edge portions of the anode portions of the plurality of capacitor elements. It is preferable to have a connecting member fixing step of fixing a connecting member made of a conductive material for electrical connection across the end portions of all the anode portions.

  Because the connection member fixing step of fixing the connection member made of a conductive material for electrically connecting the end portions of the anode portions of the plurality of capacitor elements across the end portions of all the anode portions is performed. The end portions of the anode portion of the capacitor element can be electrically connected to each other through the connection member.

  In the laser cutting step, the slit is preferably formed by laser irradiation by laser scanning.

  Further, in the laser scanning of the laser cutting step, laser irradiation is performed on the capacitor elements other than the capacitor element arranged in the lowermost layer while moving from one end to the other end in the longitudinal direction of the slit to be formed. A first longitudinal scanning step, a widthwise scanning position moving step of moving the laser irradiation position in the widthwise direction of the slit at the other longitudinal end of the slit to be formed, and a longitudinal direction of the slit to be formed At least a second longitudinal scanning step in which laser irradiation is performed while moving from the other end to the other end, and the width of the slit is defined by the total amount of movement and the beam spot diameter in the width direction scanning position moving step, It is preferable that at least the first longitudinal scanning step is performed on the capacitor element arranged in the capacitor element.

  In the laser scanning of the laser cutting step, the capacitor elements other than the capacitor element arranged in the lowermost layer are irradiated with laser while moving from one end to the other end in the width direction of the slit to be formed. One width direction scanning step, a longitudinal scanning position moving step of moving the laser irradiation position in the longitudinal direction of the slit at the other end in the width direction of the slit to be formed, and other width direction of the slit to be formed At least a second width direction scanning step in which laser irradiation is performed while moving from one end to the other end, and the length in the longitudinal direction of the slit is defined by the total amount of movement in the longitudinal direction scan position moving step, The arranged capacitor element has a longitudinal direction in which laser irradiation is performed while moving from one end to the other end in the longitudinal direction of the slit to be formed. It is preferable that at least performing scanning process.

  Further, in the laser scanning of the laser cutting step, the upper layer irradiation step of performing laser irradiation while scanning within a predetermined range in the region where the slit is formed in the upper capacitor element, and the stacking direction of the lower capacitor element It is preferable to repeatedly perform a multi-layer laser irradiation step in the stacking direction in which a lower layer irradiation step of performing laser irradiation while scanning in a range narrower than the predetermined range at a position corresponding to the predetermined range in FIG.

  Since the slit is formed by laser irradiation by laser scanning, the slit can be formed very easily.

  The present invention also includes an anode part made of a valve metal having an oxide film layer formed on the surface, and a cathode part formed in a layered manner having a solid electrolyte layer in a predetermined region of the surface. A plurality of plate-like capacitor elements are provided, and the plurality of capacitor elements are stacked so that the end portions of the anode portions face each other, and the cathode portions are stacked on each other to electrically connect each other. A solid electrolytic capacitor connected in parallel is provided.

  In the capacitor element, the direction in which the portion of the anode part where the cathode part is not formed from the part in which the cathode part is formed in a layer form is defined as a projecting direction, and the direction in which the capacitor element is laminated is defined as a laminating direction. When the width direction is the direction perpendicular to the protruding direction and the stacking direction, the end portions of the anode portions of all the capacitor elements extend from one end to the other end in the width direction at the end portions of the anode portions. A slit is formed by laser irradiation from above the stacking direction, and has a cut surface of the anode part generated by cutting off the edge part of the anode part located in the projecting direction from the slit, Each cut surface is flush with the stacking direction of the plurality of capacitor elements.

  Since each cut surface is flush with the stacking direction of a plurality of capacitor elements, for example, a plate-like connection member made of a conductive material is fixed across the end portions of all anode portions on the cut surface. When the parts are electrically connected, the electrical connection between the connection member and the end of the anode part can be ensured.

  As described above, it is possible to provide a method for manufacturing a solid electrolytic capacitor and a solid electrolytic capacitor capable of cutting a plurality of stacked capacitor elements up to the lowest layer and aligning the end faces of the capacitor elements in the stacking direction with high accuracy. it can.

  A method of manufacturing a solid electrolytic capacitor and a solid electrolytic capacitor according to an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the solid electrolytic capacitor 1 is molded so as to cover the four capacitor elements 10 to 40, the printed board 50, the connection member 60, and the four capacitor elements 10 to 40 that are stacked. And a mold part (not shown).

  The four capacitor elements 10 to 40 have the same shape and the same configuration, respectively, and include anode parts 11 to 41 and cathode parts 12 to 42 as shown in FIG. In the following description that will be described with reference to FIG. 2, the configuration of the four capacitor elements 10 to 40 is the same. Therefore, only the capacitor element 10 is illustrated, and the other capacitor elements 20 to 40 are described. Omitted.

  The anode portion 11 has a substantially rectangular plate shape, the long side is oriented in the left-right direction shown in FIGS. 1 and 2, and the left end portion 11B shown in FIG. As shown, a convex portion 11C that protrudes outward in a substantially rectangular shape is provided.

  Here, in the capacitor element 10, the portion of the anode portion 11 where the cathode portion 12 is not formed protrudes from the portion where the cathode portion 12 described later is formed, that is, the left direction in FIG. The direction in which 10 to 40 are stacked is defined as the stacking direction, and the direction perpendicular to the projecting direction and the stacking direction, that is, the direction connecting the front and back of the paper surface of FIG.

  At this time, as will be described later, slits 10a to 40a (FIG. 3 and the like) are formed by laser irradiation from the upper side in the stacking direction from one end to the other end in the width direction at the end portion 11B of the anode portion 11. Is done. A cut surface of the anode portion 11 formed by cutting off the edge portions 13 to 43 (FIG. 3 and the like) of the anode portion 11 located in the projecting direction from the slits 10a to 40a is provided with a convex portion 11C. The contour of the end portion 11B is defined. Since this cut surface is generated by laser irradiation from above in the stacking direction of the capacitor elements 10 to 40 as will be described later, the cut surface of the anode parts 11 to 41 of the capacitor elements 10 to 40 is shown on the left side shown in FIG. The contours of the end portions 11B to 41B are flush with each other in the stacking direction.

  The anode portion 11 is made of aluminum which is a valve metal, and as shown in FIG. 2, the surface thereof is roughened (enlarged) by etching to increase the surface area. It is porous. An insulating oxide film layer (dielectric layer) 11A is formed on the entire porous surface by chemical conversion treatment (anodic oxidation). The anode portion 11 has a length in the longitudinal direction of about 10 mm and a width of about 5 mm, and the thickness, that is, the width in the vertical direction shown in FIG. 2 is about 100 μm.

  A predetermined region on the surface of the anode part 11, that is, a position of approximately 2/3 of the length in the left-right direction of the anode part 11 from the right end part to the left end part 11B of the anode part 11 shown in FIG. A solid electrolyte layer 12A composed of a conductive polymer is formed in the entire region up to. The solid electrolyte layer 12A is provided by being laminated on the oxide film layer 11A, and the portion of the solid electrolyte layer 12A facing the oxide film layer 11A is in a porous formed on the surface of the anode part 11 by etching. It has entered. A graphite paste layer 12B and a silver paste layer 12C are laminated in this order on the solid electrolyte layer 12A, and the solid electrolyte layer 12A, the graphite paste layer 12B, and the silver paste layer 12C constitute the cathode portion 12. . The graphite paste layer 12B and the silver paste layer 12C are formed on the solid electrolyte layer 12A so as to cover the areas of the anode portion 11 and the oxide film layer (dielectric layer) 11A where the solid electrolyte layer 12A is formed. .

  A resist 13 made of an insulating epoxy resin or the like is provided at the boundary between the cathode portion 12 and the region of the anode portion 11 on the left side 11B shown in FIG. 2 where the cathode portion 12 is not provided. Is provided. The resist 13 is formed by capillary action on the surface of the anode portion 11 that is porous when the chemical conversion foil that becomes the anode portion 11 is immersed in the solution in order to form the solid electrolyte layer 12A on the anode portion 11. In order to prevent the solution from rising toward the left side in FIG. 2 from a predetermined region, and to secure the left end portion 11B shown in FIG. 2 of the anode portion 11 where the solid electrolyte layer 12A is not formed. Is provided.

  As shown in FIG. 1, the four capacitor elements 10 to 40 are configured such that the cathode portions 12 to 42 are stacked on each other. Since the cathode portions 12 to 42 are formed on the plate-like anode portions 11 to 41, the cathode portions 12 to 42 have upper surfaces 10A to 40A and lower surfaces 10B to 40B substantially perpendicular to the thickness direction of the anode portions 11 to 41. is doing. As shown in FIG. 1, the upper surface 10 </ b> A of the first capacitor element 10 and the lower surface 20 </ b> B of the second capacitor element 20 that form the first layer of the four capacitor elements 10 to 40 that are stacked are bonded together by the conductive adhesive 71. The upper surface 20A of the second capacitor element 20 and the lower surface 30B of the third capacitor element 30 are bonded by the conductive adhesive 71, and the upper surface 30A of the third capacitor element 30 and the lower surface 40B of the fourth capacitor element 40 are electrically conductive. Bonded by the adhesive 71. Accordingly, the cathode portions 12 to 42 of the four capacitor elements 10 to 40 are electrically connected, and the left ends of the anode portions 11 to 41 of the four capacitor elements 10 to 40 shown in FIG. Coupled with the portions 11B to 41B being electrically connected, the four capacitor elements 10 to 40 are electrically connected in parallel.

  The portions of the end portions 11B to 41B of the anode portions 11 to 41 where the cathode portions 12 to 42 of the four capacitor elements 10 to 40 are not provided are silver paste compared to the portion where the cathode portions 12 to 42 are provided. The layer 12C is thin because it is not formed. Therefore, as shown in FIG. 1, in the stacking direction of the capacitor elements 10 to 40, the left end portions 11 </ b> B to 41 </ b> B of the anode portions 11 to 41 are adjacently stacked at a predetermined interval. Is arranged.

  The four capacitor elements 10 to 40 stacked are placed on a printed circuit board 50 having substantially the same shape as the anode portions 11 to 41. The printed board 50 is, for example, a printed board 50 made of epoxy resin. The four capacitor elements 10 to 40 are placed on the printed circuit board 50 so as to coincide with the printed circuit board 50 in shape. The printed circuit board 50 faces the cathode portion 12 of the first capacitor element 10 and the lower surface 11B of the anode portion 11 among the four capacitor elements 10 to 40 stacked.

  First conductive patterns 51A and 51B and second conductive patterns 52A and 52B are provided on the front surface 50A and the back surface 50B of the printed circuit board 50, respectively. The first conductive pattern 51A and the second conductive pattern 52A on the front surface 50A are electrically connected to the first conductive pattern 51B and the second conductive pattern 52B on the back surface 50B through the through holes 50a and 50b, respectively. Yes. The first conductive pattern 51A is disposed at a position facing the left end portion 11B of the anode portion 11 of the first capacitor element 10 shown in FIG. 1, and the second conductive pattern 52A is the first capacitor element. 10 are arranged at positions facing the cathode portions 12.

  The first conductive pattern 51B and the second conductive pattern 52B on the back surface of the printed circuit board 50 are so-called user terminals that are mounted on an electronic circuit (not shown), and the first conductive pattern 51A on the front surface of the printed circuit board 50. The second conductive pattern 52A is made of the same metal material. The left end portion 11B shown in FIG. 1 of the anode portion 11 is electrically connected to the first conductive pattern 51A on the surface of the printed circuit board 50 via a connecting member 60 described later. Further, the cathode portion 12 is electrically connected to the second conductive pattern 52 </ b> A by the conductive adhesive 71.

  Connection members 60 are provided at the positions of the left end portions 11B to 41B shown in FIG. 1 of the anode portions 11 to 41 of the four capacitor elements 10 to 40. As shown in FIG. 6, the connection member 60 has a connection portion main body 61 and a bottom portion 62 each having a substantially rectangular plate shape, and one short side of the bottom portion 62 is entirely connected to the connection portion main body. One long side of 61 is integrally connected to a substantially central position in the longitudinal direction. The connecting portion main body 61 and the bottom portion 62 are connected at a substantially vertical angle to form a substantially L shape. Accordingly, the connection portion main body 61 extends from the bottom portion 62 in the stacking direction of the stacked capacitor elements 10 to 40.

  As shown in FIG. 1, the connecting portion main body 61 is in contact with and fixed to the end portions of the anode portions 11 to 41, and the left side of all the anode portions 11 to 41 shown in FIG. The convex portions 11C to 41C at the end portions of the anode portions 11 to 41 are in a direction intersecting with the stacking direction of the capacitor elements 10 to 40 in a state where the convex portions 11C to 41C of the end portions 11B to 41B are in contact with each other. Each of the end portions 11B to 41B of the anode portions 11 to 41 is irradiated with laser from the outside of the connection member 60 that is the opposite side to the abutting side, that is, from the left side to the right side in FIG. Are electrically connected to each other. The connecting member 60 is made of Ni.

  As described above, the contour shapes of the end portions 11B to 41B of the capacitor elements 10 to 40 provided with the convex portions 11C to 41C are the stacking directions of the capacitor elements 10 to 40 in the anode portions 11 to 41 of the capacitor elements 10 to 40, respectively. Since it is a cut surface generated by laser irradiation from above and is flush with the stacking direction, the connecting portion main body 61 uniformly contacts the end portions 11B to 41B, and each end of the anode portions 11 to 41 The electrical connection between the portions 11B to 41B and the connection member 60 can be ensured.

  The bottom 62 of the connection member 60 is disposed between the left end 11B of the anode 11 of the first capacitor element 10 shown in FIG. 1 and the first conductive pattern 51A of the printed circuit board 50. The substrate 50 is in contact with the first conductive pattern 51A. The bottom 62 is electrically connected to the first conductive pattern 51 </ b> A of the printed circuit board 50 by receiving laser irradiation in the stacking direction of the capacitor elements 10 to 40, i.e., from the top to the bottom in FIG. 1.

  As described above, the left end portions 11B to 41B shown in FIG. 1 of the anode portions 11 to 41 are provided with the convex portions 11C to 41C. Therefore, as shown in FIG. The two corners sandwiching the short side are cut out and removed. In contrast, the bottom 62 has a rectangular shape as shown in FIG. The bottom portion 62 is arranged so as to overlap the convex portions 11C to 41C of the left end portions 11B to 41B shown in FIG. 1 of the anode portions 11 to 41 in the stacking direction of the capacitor elements 10 to 40. The width in the longitudinal direction of 62, that is, the length in the left-right direction in FIG. 6, is the width of the convex portions 11C to 41C in the width direction with respect to the extending direction of the anode portions 11 to 41, that is, the convex portions 11C to 41C in FIG. Since it is larger than the length in the left-right direction, the bottom 62 has a non-overlapping portion 62A that does not overlap with the anode portions 11-41 of any of the capacitor elements 10-40 in the stacking direction of the capacitor elements 10-40.

  In the method of manufacturing a solid electrolytic capacitor, first, a capacitor element manufacturing process is performed. In the actual capacitor element manufacturing process, a plurality of capacitor elements are manufactured at the same time. Here, for convenience of explanation, the process of manufacturing one capacitor element 10 is a single capacitor element manufacturing process. First, an aluminum film that is formed on the surface with an oxide film layer 11 </ b> A and serves as the anode portion 11, that is, a chemical conversion foil is punched out so that one end has the shape of the anode portion 11. At this time, as will be described later, the portion of the conversion foil on which the cathode layer is formed includes the other end portion of the conversion foil on which the cathode portions of other capacitor elements manufactured at the same time are formed, and an extra formation that does not become a product. It is in a state of being connected through the foil portion. In a laser cutting step performed immediately before performing a connection step described later, the excess chemical conversion foil portion is cut and removed.

  Next, using a screen printing method, a resist 13 is formed at a predetermined position of the anode portion 11 and a boundary between the cathode portion 12 and the anode portion 11. Next, when the chemical conversion foil is punched as described above, a portion where the oxide film layer 11A is not formed is formed in the punched cross section, but the oxide film layer 11A is formed again in this portion in order to generate the oxide film layer 11A. Perform re-formation.

  Next, a reaction solution for forming a solid electrolyte layer 12A on a predetermined region with the resist 13 as a boundary, that is, a portion of the chemical conversion foil corresponding to a portion on the right side of the resist 13 of the anode portion 11 shown in FIG. The solid electrolyte layer 12A, that is, the conductive polymer layer is formed by dipping in the substrate and performing chemical oxidative polymerization. Since the surface of the anode part 11 is made porous by etching, the silver paste layer 12C cannot be formed directly, so the solid electrolyte layer 12A is formed in preparation for forming the silver paste layer 12C.

  Next, a graphite paste layer 12B and a silver paste layer 12C are stacked in this order on the conductive polymer layer. For forming the graphite paste layer 12B and the silver paste layer 12C, a dipping method, a screen printing method, a spray coating method, or the like is used. The above is the capacitor element manufacturing process. By performing this capacitor element manufacturing process four times, four capacitor elements 10 to 40 are manufactured.

  Next, a lamination process is performed. In the laminating step, the four capacitor elements 10 to 40 are laminated so that the left end portions 11B to 41B shown in FIG. 1 of the anode portions 11 to 41 are adjacent to each other, and the cathode portions 12 to 42 are arranged together. Laminate each other. A conductive adhesive 71 is applied between the cathode portions 12 to 42, and the cathode portions 12 to 42 are electrically connected to each other by the conductive adhesive 71. As the conductive adhesive 71, for example, a silver-epoxy adhesive is used.

  Next, the four capacitor elements 10 to 40 in the stacked state are cut from the portion of the excess chemical conversion foil that does not become a product, so that the end portions 11B to 41B of the anode portions 11 to 41 have a desired outline shape, A laser cutting step for forming the rectangular capacitor elements 10 to 40 is performed. In the laser cutting process, at the end portions 11B to 41B of the anode portions 11 to 41 of all the capacitor elements 10 to 40, the one end 41F in the width direction described above (FIG. 3) to the other end 11G to 41G or the other end 11G. By irradiating a laser beam from above 41G to one end 41F or the like from above in the stacking direction, slits 10a to 40a as shown in FIG. 3 are formed, and anode portion 11 located in the above-described protruding direction from slits 10a to 40a. The edge part of -41, ie, the left side parts 13-43 shown by FIG. 3, is cut off.

  Laser irradiation is performed by laser scanning. The laser used in the laser cutting process is a YAG laser, the wavelength is 1064 nm, and an fθ lens of F100 mm to F300 mm and an expander X8 are used. The spot diameter of the laser is about φ60 μm, and the aperture diameter is φ2 mm.

  The output is 5 W to 10 W at @ 5 kHz to @ 15 kHz, and the scan speed is 50 mm / sec to 100 mm / sec. The distances (WD) between the surfaces of the end portions 11B to 41B of the anode portions 11 to 41 of the capacitor elements 10 to 40 to be irradiated and the laser beam emitting portions are 100 mm to 200 mm, respectively, and the end portions of the anode portions 11 to 41 The surface of 11B to 41B is focused and irradiated with laser.

  Regarding the laser scanning, specifically, the left side portion 13 shown in FIG. 3 of the end portions 11B to 41B of the anode portions 11 to 41 of the capacitor elements 10 to 40 with the position of the slits 10a to 40a formed first as a boundary. -43 and the right-side portions 14-44 are held by a jig (not shown), and the uppermost layer 40 of the stacked four-layer capacitor elements 10-40 is from one end to the other end in the longitudinal direction of the slit 40a to be formed. A first longitudinal scanning step is performed in which laser irradiation is performed while moving in the direction toward the front, that is, in the direction from the back to the front of FIG. The position where laser scanning is performed at the end 41B of the anode 41 of the capacitor element 40 is a position A that defines the outline of the end 41B of the anode 41 of the capacitor 40 as shown in FIG. The width indicated by position A corresponds to the beam spot diameter of the laser.

  Next, at the position of the other end in the longitudinal direction of the slit 40a to be formed, that is, the position closest to the front side of the paper surface of the capacitor element 40 in FIG. 4, the laser irradiation position is set in the width direction of the slit 40a, that is, in FIG. The width direction scan position moving step is performed to move to the left. The moving distance is 10 μm.

  Next, a second longitudinal scanning step is performed in which laser irradiation is performed while moving the slit 40a in the direction from the other end to the one end in the longitudinal direction, that is, in the direction from the front side to the back side in FIG. At this time, the position where laser scanning is performed at the end 41B of the anode 41 of the capacitor element 40 is the position B shown in FIG. Similarly to the position A, the width indicated by the position B also matches the beam spot diameter of the laser. The same applies to positions C to E described later.

  Next, a width direction scan position moving step is performed at the position of one end of the slit 40a in the longitudinal direction, that is, the position closest to the back side of the paper surface of the capacitor element 40 in FIG. The first longitudinal scanning step is performed at position C. Then, the width direction scan position moving step is performed at the position of the other end in the longitudinal direction of the slit 40a, that is, the position closest to the front side of the paper surface of the capacitor element 40 in FIG. The second longitudinal scanning step is performed at position D. Subsequently, a width direction scan position moving step is performed at the position of the other end in the longitudinal direction of the slit 40a, that is, the position closest to the back side of the paper surface of the capacitor element 40 in FIG. The first longitudinal direction scanning step is performed at the position E of the portion 41B, and the laser scan for the capacitor element 40 is completed.

  The width of the slit 40a formed by laser scanning is defined by the total amount of movement in the width direction scan position moving step and the beam spot diameter. That is, the moving distance in one width direction scan position moving step is 10 μm as described above, the beam spot diameter is 60 μm, and the width direction scan position moving step is performed four times. The width of the slit 40a at the end 41B of 41 is 100 μm.

  Next, laser scanning is performed on the capacitor element 30. First, the first longitudinal scanning step is performed at the position A (FIG. 4) of the end 31B of the anode 31 of the capacitor element 30, and the position of the other end in the longitudinal direction of the formed slit 30a, that is, the capacitor of FIG. The width direction scan position moving step is performed at the position closest to the front side of the surface of the element 30, and the second longitudinal direction scan step is performed at the position B of the end portion 31 </ b> B of the anode portion 31 of the capacitor element 30.

  Subsequently, the width direction scan position moving step is performed at the position of one end in the longitudinal direction of the slit 30a to be formed, that is, at the position closest to the back side of the paper surface of the end portion 31B of the anode portion 31 in FIG. The first longitudinal scanning process is performed at the position C of the end 31B. Next, the width direction scan position moving step is performed at the position of the other end in the longitudinal direction of the slit 30a to be formed, that is, the position closest to the front side of the paper surface of the capacitor element 30 in FIG. The second longitudinal direction scanning step is performed at the position D of the end portion 31B, and the laser scanning on the capacitor element 30 is completed.

  In the capacitor element 40, since the width from the position A to the position E is the width of the slit 40a, as shown in FIG. 5, compared with the capacitor element 30 where the width from the position A to the position D is the width of the slit 30a. And it is getting wider. The width of the slit 30a at the end 31B of the anode 31 of the capacitor element 30 is 90 μm. For this reason, the capacitor element 30 can be irradiated with laser to form a slit 30a having a desired width.

  Next, laser scanning is performed on the capacitor element 20. First, the first longitudinal scanning step is performed at the position A of the end portion 21B of the anode portion 21 shown in FIG. 4, and the position of the other end in the longitudinal direction of the slit 20a to be formed, that is, the capacitor element 20 of FIG. The width direction scan position moving step is performed at a position closest to the front side of the paper surface, and the second longitudinal direction scan step is performed at the position B of the end portion 21B of the anode portion 21 of the capacitor element 20.

  Subsequently, a width direction scan position moving step is performed at the position of one end in the longitudinal direction of the slit 20a to be formed, that is, at the position closest to the back side of the paper surface of the end 21B of the anode 21 in FIG. The first longitudinal scanning process is performed at the position C of the end 21B, and the laser scanning for the capacitor element 20 is completed.

  In the capacitor element 30, since the width from the position A to the position D is the width of the slit 30a, as shown in FIG. 5, compared with the capacitor element 20 where the width from the position A to the position C is the width of the slit 20a. And it is getting wider. The width of the slit at the end portion 21B of the anode portion 21 of the capacitor element 20 is 80 μm. For this reason, laser irradiation can be performed on the capacitor element 20 to form a slit 20a having a desired width.

  Next, laser scanning is performed on the capacitor element 10. Specifically, the first longitudinal scanning step is performed at the position A of the end portion 11B of the anode portion 11 shown in FIG. 4, and the position of the other end in the longitudinal direction of the slit 10a to be formed, that is, the capacitor of FIG. The width direction scan position moving step is performed at a position closest to the front side of the surface of the element 10, the second longitudinal direction scanning step is performed at the position B of the end portion 11 </ b> B of the anode portion 11 of the capacitor element 10, and the laser scan for the capacitor element 10 is performed. Ends.

  In the capacitor element 20, since the width from the position A to the position C is the width of the slit 20a, as shown in FIG. 5, it is compared with the capacitor element 10 in which the width from the position A to the position B is the width of the slit 10a. And the width of the slit is wide. The slit width at the end portion 11B of the anode portion 11 of the capacitor element 10 is 70 μm. For this reason, the slit 10a can be formed by irradiating the capacitor element 10 with laser. The above is the laser cutting process.

  In the laser cutting step, slits 20 a to 40 a having a width wider than the slit 10 a formed in the capacitor element 10 are formed in the end portions 21 B to 41 B of the anode parts 21 to 41 of the capacitor elements 20 to 40 other than the capacitor element 10. Therefore, it is considered that the end portion 11B of the anode portion 11 of the capacitor element 10 can be irradiated without weakening the reaching intensity of the laser beam, and the slit 10a is formed in the end portion 11B of the anode portion 11 of the capacitor element 10. can do.

  Therefore, by laser irradiation, the left side portions 13 to 43 in FIG. 3 which are the edge portions of the anode portions 11 to 41 of the plurality of capacitor elements 10 to 40 stacked can be cut off by laser irradiation. As a result, the cut surfaces of the anode portions 11 to 41 generated by cutting off the edge portions 13 to 43 of the anode portions 11 to 41 by laser irradiation are surfaces in the stacking direction of the capacitor elements 10 to 40 as described above. Can be one. For this reason, the dimensional accuracy of the manufactured solid electrolytic capacitor 1 can be improved, and the yield can be improved.

  Further, after cutting the edge part of the anode part of the laminated capacitor element by laser irradiation, it is not necessary to repeat the process of removing the part of the cut anode part. When the unnecessary portion is removed, it is possible to prevent the portion that becomes the anode portion of the solid electrolytic capacitor from being deformed, and the manufacturing process can be simplified.

  Next, a connection process is performed. In the connecting step, as shown in FIG. 6, the connecting members 60 prepared separately from the four stacked capacitor elements 10 to 40 are connected to the anode portions 11 to 41 of the stacked capacitor elements 10 to 40. A connecting member fixing step of electrically connecting the four capacitor elements 10 to 40 in parallel with each other is performed by electrically connecting to the left end portions 11B to 41B shown in FIG. Specifically, first, parallel to the convex portion 11C of the left end portion 11B shown in FIG. 1 of the anode portion 11 of the first capacitor element 10 forming the first layer of the four capacitor elements 10 to 40 stacked. In a state where the bottom portion 62 is disposed oppositely, the connection portion main body 61 of the connection member 60 is brought into contact with the convex portions 11C to 41C of the end portions 11B to 41B of all the anode portions 11 to 41. Thus, a non-overlapping portion 62 </ b> A that does not overlap with the anode portions 11 to 41 of any of the capacitor elements 10 to 40 in the stacking direction of the capacitor elements 10 to 40 is defined as the bottom portion 62.

  In addition, the arrow shown with a dashed-two dotted line in FIG. 6 only shows the positional relationship of the four capacitor | condenser elements 10-40 laminated | stacked, the connection member 60, and the printed circuit board 50. It does not mean that these three are connected by moving in the direction.

  Next, the direction crossing the stacking direction of the capacitor elements 10 to 40 from the side opposite to the side of the connecting portion main body 61 that contacts the end portions 11B to 41B of the anode portions 11 to 41, that is, the left side shown in FIG. Specifically, the connection portion main body 61 is irradiated with laser in a direction perpendicular to the stacking direction. As the laser, YAG laser spot welding is used, and laser irradiation is performed by drawing a wave from one end of the connecting portion main body 61 in the longitudinal direction to the other end. Thereby, the connection part main body 61 is electrically connected to each end part 11B-41B of the anode parts 11-41. The above is the connecting member fixing step.

  Next, a printed circuit board connection process is performed. In the printed circuit board connecting step, as shown in FIG. 6, the four stacked capacitor elements 10 to 40 and the four stacked capacitor elements are prepared on the printed circuit board 50 prepared separately from the connection member 60. 10 to 40 and the connection member 60 are placed and electrically connected. Specifically, first, the cathode portions 12 to 42 to which the conductive adhesive 71 is applied are brought into contact with the second conductive pattern 52A of the printed circuit board 50, and the bottom portion 62 of the connection member 60 is set to the first conductive pattern. Abutting on the pattern 51A, from the stacking direction of the capacitor elements 10 to 40 with respect to the non-overlapping portion 62A, that is, from the upper direction shown in FIG. 1 or 2, to the position of the circle shown by the broken line in FIG. Irradiate the laser. As a result, the bottom 62 of the connecting member 60 is electrically connected to the first conductive pattern 51A of the printed circuit board 50, and the cathode portions 12 to 42 are electrically connected to the second conductive pattern 52A.

  Thereafter, molding is performed to protect the solid electrolytic capacitor 1, cutting is performed, aging is performed to repair a damaged portion, and the entire method of manufacturing the solid electrolytic capacitor is performed through characteristic inspection and appearance inspection. The process ends.

  The solid electrolytic capacitor and the method for manufacturing the solid electrolytic capacitor according to the present invention are not limited to the above-described embodiments, and various modifications and improvements can be made within the scope described in the claims. For example, the connecting member is not limited to the shape of the connecting member 60 according to the present embodiment. Further, the position of the end of the anode part of the capacitor element to which the connection member is fixed is not limited to the position according to the present embodiment.

  For example, as shown in FIG. 7, the connecting portion main body 91 of the connecting member 90 is not the protruding end edges 11D to 41D of the protruding portions 11C to 41C of the end portions 11B to 41B of the anode portions 11 to 41 but the protruding portions 11C. You may make it weld to the side surfaces 11E-41E of -41C. In the present embodiment, the connection portion main body 61 of the connection member 60 exists at the left end portion of the capacitor element 1 shown in FIG. 1, but the connection portion main body serves as the side surfaces 11E to 41E of the convex portions 11C to 41C. 1, it is not necessary to arrange the connecting portion main body 61 at the position corresponding to the left end portion of the capacitor element shown in FIG. 1, and the thickness of the connecting portion main body 91 in the direction corresponding to the left-right direction shown in FIG. The length of the capacitor element can be shortened by this amount.

  In the present embodiment, the slit width is wider in the upper layer than in the lower layer, but the width of the upper slit and the width of the lower slit may be the same except for the lowermost layer. Even in this case, the width of the slits other than the lowermost layer needs to be wider than the width of the lowermost slit. By doing in this way, a slit can be reliably formed in the edge part of the anode part of the capacitor element of the lowest layer.

Moreover, although YAG laser was used as a laser, it is not limited to this. For example, a YVO ₄ laser may be used. As an example, the wavelength is 1064 nm, and an fθ lens of F100 mm to F300 mm is used. The spot diameter of the laser is about φ60 μm. The output is from 5 W to 20 W at @ 50 kHz to @ 80 kHz, and the scan speed is from 50 mm / sec to 100 mm / sec. The distance (WD) between the surfaces of the end portions 11B to 41B of the anode portions 11 to 41 of the capacitor elements 10 to 40 to be irradiated and the laser beam emitting portion is 50 mm to 150 mm, and the end portions 11B of the anode portions 11 to 41 are used. A laser beam is focused on the surface of ~ 41B.

  Further, in the laser scanning in the laser cutting step of the present embodiment, the first longitudinal scanning step, the width direction scanning position moving step, and the second longitudinal scanning step were performed, but not limited thereto, Any laser scan may be performed as long as a slit having a desired width is formed.

  For example, a capacitor element other than the capacitor element arranged in the lowermost layer includes a first width direction scanning step in which laser irradiation is performed while moving from one end to the other end in the width direction of the formed slit, and the slit formed A longitudinal scan position moving step of moving the laser irradiation position in the longitudinal direction of the slit at the other end in the width direction, and a second width direction in which laser irradiation is performed while moving from the other end of the slit in the width direction to the one end At least a scanning step, and at least a longitudinal scanning step of irradiating a laser while moving from one end to the other end of the slit to be formed on the capacitor element arranged in the lowermost layer. Also good. In this case, the length of the slit in the longitudinal direction is defined by the total amount of movement in the longitudinal scan position moving step.

  Further, as another laser scanning method, for example, an upper layer irradiation step of performing laser irradiation while scanning within a predetermined range in a region where a slit is formed in the upper layer capacitor element, and a predetermined direction in the stacking direction of the lower layer capacitor element A slit having a desired width may be formed by repeatedly performing a multi-layer laser irradiation step in a stacking direction in which a lower layer irradiation step of performing laser irradiation while scanning in a range narrower than a predetermined range at a position corresponding to the range is performed. .

  Moreover, although laser irradiation by laser scanning was performed to form the slits 10a to 40a, instead of this, the laser may be fixed and the slit may be formed by scanning the capacitor element relative to the laser. Good.

  The laser irradiation may be continuous irradiation or pulse irradiation.

  In addition, the width of the slit at the end portion 41B of the anode portion 41 of the uppermost capacitor element 40 is 100 μm, but is not limited thereto, and may be, for example, about 300 μm. Accordingly, the width of the slit formed at the end of the anode portion of the capacitor element other than the lowermost layer and the uppermost layer may be increased.

  Moreover, although the anode parts 11-41 were electrically connected by the connection member 60, if the anode parts 11-41 can be electrically connected, it is not necessary to use the connection member 60. FIG. For example, the end portions of the anode portion may be electrically connected by caulking. In addition, a spacer for maintaining a predetermined distance between the end portions of the anode portion may be disposed between the end portions of the anode portion.

  Moreover, the surface which receives the laser irradiation of a connection member may be roughened. By being roughened, the reflection of laser light can be reduced. For this reason, absorption of the laser beam in a connection member can be increased.

  Moreover, although the connection member 60 was provided with the bottom part 62 and the connection part main body 61, the structure which has only a connection part main body may be sufficient. Further, the dimensions of the solid electrolytic capacitor are not limited to the values according to the present embodiment. Further, the laminated capacitor elements 10 to 40 are arranged on the printed board 50, but the invention is not limited to this. For example, it may be placed on a lead frame instead of the printed board.

  Moreover, although the valve action metal which comprises the anode parts 11-41 was comprised with aluminum, it is not limited to this. For example, tantalum or niobium may be used. Moreover, although the connection member 60 was comprised with Ni, it is not limited to this. For example, conductive metals such as SUS, iron, aluminum, copper, phosphor bronze, Mo, Cr, and FeNi alloy may be used. For example, the trade name “Hitachi High Clad” manufactured by Hitachi Cable, Ltd. A so-called clad material in which dissimilar metals are metallurgically bonded may be used. Further, although four capacitor elements 10 to 40 are provided, the number is not limited to four.

  Moreover, although the connection part main body 61 and the bottom part 62 were connected integrally, it is not limited to this, You may comprise by connecting the connection part main body and bottom part which were prepared as a different body beforehand by welding etc. .

  Further, the laser irradiation is performed so as to draw a wave from one end to the other end in the longitudinal direction of the connection portion main body 61, but is not limited to this. For example, the irradiation may be performed so as to draw a wave from one end to the other end in the width direction of the connection portion main body 61, and the projections 11C to 41C of the end portions 11B to 41B of the anode portions 11 to 41 are applied. You may irradiate a laser intermittently with a spot only to the position of the connection part main body 61 which touches.

  The solid electrolytic capacitor and the method for manufacturing the solid electrolytic capacitor of the present invention are useful in the fields of a solid electrolytic capacitor configured by laminating a large number of capacitor elements and a method for manufacturing the solid electrolytic capacitor.

Sectional drawing which shows the solid electrolytic capacitor by embodiment of this invention. Sectional drawing which shows the capacitor | condenser element which comprises the solid electrolytic capacitor by embodiment of this invention. The conceptual diagram which shows the slit formed of the laser cutting process of the manufacturing method of the solid electrolytic capacitor by embodiment of this invention. Explanatory drawing for demonstrating the laser cutting process of the manufacturing method of the solid electrolytic capacitor by embodiment of this invention. Explanatory drawing which shows the slit formed of the laser cutting process of the manufacturing method of the solid electrolytic capacitor by embodiment of this invention. 1 is an exploded perspective view showing a solid electrolytic capacitor according to an embodiment of the present invention. The disassembled perspective view which shows the modification of the connection member of the solid electrolytic capacitor by embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solid electrolytic capacitor 10-40 Capacitor element 10a-40a Slit 11-41 Anode part 11A Oxide film layer 11B-41B End part 12-42 Cathode part 12A Solid electrolyte layer 12B Graphite paste layer 12C Silver paste layer 13-43 Edge part 41F One end 41G The other end 60, 70 Connection member 61, 71 Connection part main body 62, 72 Bottom part 62A Non-overlapping part

Claims (8)

A capacitor element manufacturing step including a step of forming a cathode portion having a solid electrolyte layer in a predetermined region on the surface of an anode portion formed of an oxide film layer on the surface and made of a valve metal;
A plurality of capacitor elements manufactured by performing the capacitor element manufacturing step a plurality of times, and a stacking step of stacking and arranging the cathode portions so that the ends of the anode portions are adjacent to each other; ,
In the capacitor element, the direction in which the portion of the anode part where the cathode part is not formed from the part in which the cathode part is formed in a layer form is defined as the projecting direction, and the direction in which the capacitor element is laminated is defined as the laminating direction. When the width direction is the direction perpendicular to the protruding direction and the stacking direction, laser irradiation is performed from above the stacking direction from one end to the other end of the anode section of all the capacitor elements. A laser cutting step of forming a slit by cutting off the edge portion of the anode portion located in the projecting direction from the slit;
A method of manufacturing a solid electrolytic capacitor having a connecting step of electrically connecting the plurality of stacked capacitor elements in parallel with each other,
In the laser cutting step, the width of the slit of the capacitor element other than the capacitor element arranged in the lowermost layer in the stacking direction is larger than the width of the slit of the capacitor element arranged in the lowermost layer in the stacking direction. And forming a slit having a width wider than the beam spot diameter of the laser in each of the plurality of capacitor elements.   The laser cutting step is characterized in that the capacitor element disposed in the lower layer in the stacking direction is formed with the slit having a narrower width than the capacitor element disposed in the upper layer in the stacking direction. A method for producing a solid electrolytic capacitor according to 1.   The connecting step includes electrically connecting the end portions of the anode portions of the plurality of capacitor elements to the cut surface of the anode portions generated by cutting off the edge portions of the anode portions of the plurality of capacitor elements. 3. A solid electrolytic capacitor according to claim 1, further comprising a connecting member fixing step of fixing a connecting member made of a conductive material for connecting to the end portion of all the anode portions. Manufacturing method.   The method for manufacturing a solid electrolytic capacitor according to any one of claims 1 to 3, wherein, in the laser cutting step, the slit is formed by laser irradiation by laser scanning. In the laser scanning of the laser cutting step, the first and second capacitor elements other than the capacitor element arranged in the lowermost layer are irradiated with laser while moving from one end to the other end in the longitudinal direction of the slit to be formed. Longitudinal scanning step, widthwise scanning position moving step of moving the laser irradiation position in the width direction of the slit at the other end in the longitudinal direction of the slit to be formed, and the other end in the longitudinal direction of the slit to be formed At least a second longitudinal scanning step in which laser irradiation is performed while moving from one end to the other, and the width of the slit is defined by the total amount of movement and the beam spot diameter by the width direction scanning position moving step,
5. The method of manufacturing a solid electrolytic capacitor according to claim 4, wherein at least the first longitudinal scanning step is performed on the capacitor element disposed in the lowermost layer. In the laser scanning of the laser cutting step, the first width that is irradiated with the laser while moving from one end to the other end in the width direction of the slit to be formed on the capacitor elements other than the capacitor element arranged at the lowermost layer. From the other end in the width direction of the slit to be formed, a direction scanning step, a longitudinal scan position moving step in which the laser irradiation position is moved in the longitudinal direction of the slit at the other end in the width direction of the slit to be formed At least a second width direction scanning step of laser irradiation while moving to one end, the length in the longitudinal direction of the slit is defined by the total amount of movement in the longitudinal scanning position movement step,
The capacitor element disposed in the lowermost layer is at least subjected to a longitudinal scanning step in which laser irradiation is performed while moving from one end to the other end in the longitudinal direction of the slit to be formed. A method for producing a solid electrolytic capacitor.   In the laser scanning of the laser cutting step, the upper layer irradiation step of performing laser irradiation while scanning within a predetermined range in the region where the slit is formed in the upper capacitor element, and the lower layer capacitor element in the stacking direction 5. The solid electrolytic capacitor according to claim 4, wherein a multi-layer laser irradiation step in a stacking direction is repeatedly performed in which a lower layer irradiation step of performing laser irradiation while scanning in a range narrower than the predetermined range at a position corresponding to a predetermined range. Production method. A substantially plate-shaped capacitor element comprising an anode part formed of an oxide film layer on the surface and made of a valve metal, and a cathode part formed in a layered manner with a solid electrolyte layer in a predetermined region of the surface. Multiple
The plurality of capacitor elements are stacked so that the ends of the anode parts face each other, and the cathode parts are stacked together so as to be electrically connected to each other in parallel.
In the capacitor element, the direction in which the portion of the anode part where the cathode part is not formed from the part in which the cathode part is formed in a layer form is defined as the projecting direction, and the direction in which the capacitor element is laminated is defined as the laminating direction. When the width direction is the direction perpendicular to the protruding direction and the stacking direction, the end portions of the anode portions of all the capacitor elements extend from one end to the other end in the width direction at the end portions of the anode portions. A slit is formed by laser irradiation from above the stacking direction, and has a cut surface of the anode part generated by cutting off the edge part of the anode part located in the projecting direction from the slit, Each of the cut surfaces is flush with the stacking direction of the plurality of capacitor elements.

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