Four-terminal capacitor

A four-terminal capacitor comprising an anodic valve metal foil having a dielectric layer formed on the surface, a collector metal foil, a cathodic electroconductive polymer layer arranged between the anodic valve metal foil and the collector metal foil while being in direct contact with the dielectric layer and the collector metal foil, and first and second anodic terminals and first and second cathodic terminals for external connection, wherein:

• the surface of layers of the anodic valve metal foil is roughened;
• a plurality of the anodic valve metal foil layers and the collector metal foil are laminated alternately with the cathodic electroconductive polymer layer therebetween;
• first and second portions of the anodic valve metal foil layers are electrically connected to the first and second anodic terminals respectively;
• and
• first and second portions of the collector metal foil are electrically connected to the first and second cathodic terminals respectively.