US Patent 7362561 Solid electrolytic capacitor

In a solid electrolytic capacitor provided with an anode, a cathode, and a dielectric layer formed by anodization of the anode, the anode includes a first metal layer and a second metal layer. The first metal layer is made of any of metal selected from niobium, aluminum and tantalum, or an alloy containing any of metal selected from niobium, aluminum and tantalum as a main component. The second metal layer contains any of metal selected from titanium, zirconium and hafnium. Here, a part of a surface of the first metal layer is covered with the second metal layer.