A solid electrolytic capacitor includes: a valve metal support having an anode terminal region and a cathode forming region and forming an anode part; and a cathode part provided in a cathode forming region of the valve metal support. The cathode part includes: a solid electrolyte layer that is disposed on a surface of a dielectric layer provided at least on the cathode forming region of the valve metal support and contains a conductive polymer; a waterproof seed layer that is disposed on a surface of the solid electrolyte layer and contains a conductive material; and a metal plating layer disposed on a surface of the waterproof seed layer. A catalytic metal having catalytic activity for plating is provided on the surface of the waterproof seed layer.

A solid electrolytic capacitor includes: a capacitor element including an anode part and a cathode part; a substrate that supports the capacitor element; a sealing body that seals the capacitor element; a first external electrode electrically connected to the anode part; a second external electrode electrically connected to the cathode part; and an adhesive layer disposed between the capacitor element and a first surface of the substrate. At an interface between the first surface and the adhesive layer, a maximum height Rz1 of surface roughness of the first surface is 5 m or more, and a maximum height Rz2 of surface roughness of the adhesive layer is 3 m or more.

A dielectric of the present disclosure includes a tantalum compound containing fluorine and oxygen and being amorphous, and is advantageous in terms of achieving a high dielectric constant.

An improved process for forming powder, an anode of the powder and a capacitor comprising the powder is provided. The process comprises forming a dense aggregate comprising a powder and solvent in a pendular, funicular or capillary state and freeze drying the powder comprising high surface area.

To provide a thin film capacitor having high adhesion performance with respect to a circuit substrate. A thin film capacitor includes: a metal foil having a roughened upper surface; a dielectric film covering the upper surface of the metal foil and having an opening through which the metal foil is partly exposed; a first electrode layer contacting the metal foil through the opening; and a second electrode layer contacting the dielectric film without contacting the metal foil. The first and second electrode layers are formed in an area surrounded by an outer peripheral area of the upper surface of the metal foil so as not to cover the outer peripheral area. The outer peripheral area of the roughened upper surface of the metal foil is thus exposed, so that adhesion performance with respect to a circuit substrate can be enhanced.

A solid electrolytic capacitor containing a porous anode and a solid electrolyte is provided. The porous anode is formed from a sintered valve metal powder that is anodically oxidized to form a dielectric layer thereon having a dielectric thickness of about 70 nm or more, wherein the porous anode has a pore size distribution in which the pores have a size of from about 165 to about 270 nm at a pore volume corresponding to at least 80% of the total pore volume and exhibits a volumetric wet capacitance of about 3,900 F/cm.sup.3 or more. The solid electrolyte contains conductive polymer particles that are disposed within the pores of the porous anode. Further, the solid electrolytic capacitor exhibits a dielectric strength of about 0.6 V/nm or more.

A capacitor includes metallic tantalum, a solid electrolyte, and a tantalum oxide film. The tantalum oxide film is disposed between the metallic tantalum and the solid electrolyte. A first portion includes fluorine. A second portion is in contact with the first portion, the second portion being closer to the solid electrolyte than the first portion in a thickness direction of the tantalum oxide film. A fluorine concentration in the second portion is lower than a fluorine concentration in the first portion.

A dielectric of the present disclosure includes a tantalum compound containing fluorine and oxygen and being amorphous, and is advantageous in terms of achieving a high dielectric constant.

A solid electrolytic capacitor having a thickness of about 1,000 m or less is provided. The capacitor comprises a capacitor element comprising an anode component comprising a porous anode body disposed on a surface of an anode substrate. The anode substrate is formed from a valve metal composition and the porous anode body is formed from a sintered powder containing a valve metal composition and having a thickness of about 650 m or less. The capacitor element further comprises a cathode coating disposed over a dielectric and the porous anode body. The cathode coating comprises a solid electrolyte containing conductive polymer particles, wherein at least a region of the anode substrate is free of the cathode coating. An anode termination is electrically connected to the region of the anode substrate that is free of the cathode coating, and a cathode termination is electrically connected to the cathode coating.