Solid electrolytic capacitor element, solid electrolytic capacitor, and method for manufacturing solid electrolytic capacitor element

Abstract

A solid electrolytic capacitor element that includes: an anode including a valve acting metal substrate and having a front end face and a base end face; a dielectric layer on at least a first main face of the anode but excluding at least the base end face; a mask layer including an insulating material on the dielectric layer adjacent the base end face; and a cathode on the dielectric layer at a position closer to the front end face as compared to the mask layer, wherein the cathode includes: a solid electrolyte layer on the dielectric layer, and a conductive layer on the solid electrolyte layer, the solid electrolyte layer includes a protrusion adjacent the mask layer, and a largest thickness of the solid electrolyte layer at the protrusion is larger than a thickness of the solid electrolyte layer at a rest of the solid electrolyte layer excluding the protrusion.