Method of manufacturing a thin film capacitor having separated dielectric films
View Patent ↗A thin film capacitor and a method of manufacturing the same are provided. The thin film capacitor includes a metal foil, dielectric layers and internal electrode layers alternately disposed on the metal foil, and a top electrode layer on the topmost layer among the two or more dielectric layers. These layers have peripheries that define an outer profile flaring toward the metal foil as viewed from the stacking direction of the thin film capacitor, and at least one dielectric layer of two or more dielectric layers satisfies a relationship B>A>0 wherein A is a gap of the periphery of the internal electrode layer directly below the dielectric layer protruding from the periphery of the dielectric layer, and B is a gap of the periphery of the dielectric layer protruding from the periphery of the internal electrode layer or the top electrode layer directly above the dielectric layer. The thin film capacitor has a structure free from short-circuiting and reducing debris of broken dielectric material.
1. A method of manufacturing a thin film capacitor, comprising the steps of:
(a) alternately depositing dielectric films and conductive films on a metal foil to fabricate a laminated body including two or more dielectric films each disposed between the metal foil as a bottom of the laminated body and a conductive film farthest from the metal foil, each of the two or more dielectric films being separated from other of the two or more dielectric film by at least one of the conductive films such that none of the two or more dielectric films is in direct contact with any other of the two or more dielectric films; and
(b) fixing the laminated body to a support and processing the laminated body by patterning each film serially from a side of the dielectric film farthest from the metal foil such that the dielectric films and conductive films have peripheries defining an outer profile flaring toward the bottom of the laminated body as viewed from the stacking direction, and
wherein, in step (b), the dielectric films and the conductive films are processed such that at least one dielectric film of the two or more dielectric films satisfies a relationship B>A>0 wherein A is a gap of the periphery of the conductive film directly below the dielectric film protruding from the periphery of the dielectric film, and B is a gap of the periphery of the dielectric film protruding from the periphery of the conductive film directly above the dielectric film.
2. The method of manufacturing the thin film capacitor of claim 1 , wherein
in step (b), each film of the laminated body is patterned by wet etching.