# US 6,288,890 B1 · Capacitor and its manufacturing method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,288,890 B1 - Document ID: US6288890B1 - Status: Granted - Kind: B1 - Application number: 09/295,328 - Filed: 1999-04-21 - Granted: 2001-09-11 - Earliest claimed: 1998-04-21 - Assignees: Matsushita Electric Industrial Co., Ltd. - Inventors: Toshiharu Saito; Motoi Kitano; Mutsuaki Murakami - Web page: https://patentgrep.com/patent/US6288890B1 ## CPC - H01G 9/07: Dielectric layers - H01G 4/18: of synthetic material, e.g. derivatives of cellulose (H01G4/16 takes precedence) - Y10T 29/43: Electric condenser making - Y10T 29/435: Solid dielectric type - H01G: CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE (selection of specified materials as dielectric H01B3/00; capacitors having potential barriers H10D1/62, H10K10/10) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A capacitor of the present invention employs one of i) polyimide directly formed by electrodeposition, ii) organic high polymer having a specific structure formed by electrodeposition, and iii) a composite film of the organic high polymer and oxide film of a conductor as dielectrics formed on the surface-roughened conductor. The organic high polymer used in the present invention contains carboxylic radical in its molecular structure. The capacitor of the present invention further comprises an opposite electrode at least containing conductive high polymer on the dielectrics. This conductive high polymer is formed by chemical oxydation-polymerization or both chemical oxydation-polymerization and electro-polymerization. The capacitor element as configured above is strong to mechanical stress, and possible to apply pressure during lamination. By laminating many of capacitor elements as configured above, a capacitor with large capacitance but small equivalent serial resistance, small leak current, and good frequency characteristics is obtained. ## Claims ### Claim 1 A capacitor comprising a metal conductor, dielectrics formed on a surface of said metal conductor and an opposite electrode formed on a surface of said dielectrics; wherein said dielectrics are one of: polyimide directly formed on the surface of said metal conductor by electro-deposition and composite dielectrics comprising polycarboxylic acid resin derivatives formed by electro-deposition and oxide of said metal conductor. ### Claim 2 (depends on 1) The capacitor as defined in claim 1, wherein said polyimide is a reaction product of aromatic tetracarboxylic acid di-anhydride and aromatic diamine having at least one carboxylic acid radical. ### Claim 3 (depends on 1) The capacitor as defined in claim 1, wherein said polycarboxylic acid resin has at least one carboxylic acid radical in its chemical structure. ### Claim 4 (depends on 1) The capacitor as defined in claim 1, wherein said polycarboxylic acid resin is polyacrylic acid derived resin. ### Claim 5 (depends on 1) The capacitor as defined in claim 1, wherein at least a part of said opposite electrode is made of conductive high polymer. ### Claim 6 (depends on 5) The capacitor as defined in claim 5, wherein said conductive high polymer is one of polypyrrole, polythiophene, and their derivatives. ### Claim 7 (depends on 5) The capacitor as defined in claim 5, wherein said conductive high polymer is formed using one of: chemical oxydation-polymerization; and both chemical oxydation-polymerization and electro-polymerization. ### Claim 8 (depends on 1) The capacitor as defined in claim 1, wherein one of an electrode made of said metal conductor and the opposite electrode is one of a metal foil and a metal layer formed on a substrate. ### Claim 9 (depends on 8) The capacitor as defined in claim 8, wherein said metal layer is formed by one of vacuum process and plating. ### Claim 10 A capacitor comprising a surface-roughened metal conductor, a dielectrics formed on said metal conductor and an opposite electrode formed on a surface of said dielectrics; wherein said dielectrics are made of one of: polyimide directly formed on the surface of said metal conductor by electro-deposition and composite dielectrics comprising polycarboxylic acid resin derivatives formed by electro-deposition and oxide of said metal conductor. ### Claim 11 (depends on 10) The capacitor as defined in claim 10, wherein said polyimide is a reaction product of aromatic tetracarboxylic acid di-anhydride and aromatic diamine having at least one carboxylic acid radical. ### Claim 12 (depends on 10) The capacitor as defined in claim 10, wherein said polycarboxylic acid resin has at least one carboxylic acid radical in its chemical structure. ### Claim 13 (depends on 10) The capacitor as defined in claim 10, wherein said polycarboxylic acid resin is polyacrylic acid derived resin. ### Claim 14 (depends on 10) The capacitor as defined in claim 10, wherein at least a part of said opposite electrode is made of conductive high polymer. ### Claim 15 (depends on 10) The capacitor as defined in claim 10, wherein said conductive high polymer is one of polypyrrole, polythiophene, and their derivatives. ### Claim 16 (depends on 10) The capacitor as defined in claim 10, wherein said conductive high polymer is formed using one of: chemical oxidation-polymerization; and both chemical oxydation-polymerization and electro- olymerization. ### Claim 17 (depends on 10) The capacitor as defined in claim 10, wherein one of an electrode made of said metal conductor and opposite electrode is one of a metal foil and a metal layer formed on a substrate. ### Claim 18 (depends on 10) The capacitor as defined in claim 10, wherein said conductor electrode is an etched aluminum foil. ### Claim 19 (depends on 17) The capacitor as defined in claim 17, wherein said metal layer is formed by one of vacuum-process and plating. ### Claim 20 A laminated capacitor comprising a plurality of capacitor elements, said each capacitor element comprising: a surface-roughened or a perforated metal conductor; dielectrics formed on one of said surface-roughened metal conductor and perforated metal conductor; and an opposite electrode formed on a surface of said dielectrics; wherein said dielectrics are one of: polyimide directly formed on the surface of said metal conductor by electro-deposition and composite dielectrics comprising polycarboxylic acid resin derivatives formed by electro-deposition and oxide of said metal conductor. ### Claim 21 (depends on 20) The capacitor as defined in claim 20, wherein said polyimide is a reaction product of aromatic tetracarboxylic acid di-anhydride and aromatic diamine having at least one carboxylic acid radical. ### Claim 22 (depends on 20) The capacitor as defined in claim 20, wherein said polycarboxylic acid resin has at least one carboxylic acid radical in its chemical structure. ### Claim 23 (depends on 20) The capacitor as defined in claim 20, wherein said polycarboxylic acid resin is polyacrylic acid derived resin. ### Claim 24 (depends on 20) The capacitor as defined in claim 20, wherein at least a part of said opposite electrode is made of conductive high polymer. ### Claim 25 (depends on 24) The capacitor as defined in claim 24, wherein said conductive high polymer is one of polypyrrole, polythiophene, and their derivatives. ### Claim 26 (depends on 24) The capacitor as defined in claim 24, wherein said conductive high polymer is formed using one of: chemical oxydation polymerization; and both chemical oxydation-polymerization and electro-polymerization. ### Claim 27 (depends on 20) The capacitor as defined in claim 20, wherein one of an electrode made of said metal conductor and opposite electrode is one of metal foil and a metal layer formed on a substrate. ### Claim 28 (depends on 27) The capacitor as defined in claim 27, wherein said conductor is an etched aluminum foil. ### Claim 29 (depends on 27) The capacitor as defined in claim 27, wherein said metal layer is formed by one of vacuum process and plating. ### Claim 30 (depends on 20) The capacitor as defined in claim 20, wherein said opposite electrode is made of conductive high polymer and graphite. ### Claim 31 (depends on 20) The capacitor as defined in claim 20, wherein said opposite electrode is made of conductive high polymer, graphite, and conductive adhesive. ### Claim 32 (depends on 20) The capacitor as defined in claim 20, wherein each of said conductor and opposite electrode is electrically connected so that a plurality of said capacitor elements form an electrically parallel circuit. ### Claim 33 (depends on 20) The capacitor as defined in claim 20, wherein said conductor is bonded by welding. ### Claim 34 (depends on 20) The capacitor as defined in claim 20, wherein said opposite electrode is bonded by conductive adhesive to form a laminated body. ### Claim 35 (depends on 20) The capacitor as defined in claim 20, wherein an insulating layer is provided on the capacitor element to insulate said conductor from said opposite electrode.