| 摘要 |
An earth-acid metal is alloyed, whereby a metal foil comprising an earth-acid metal as a main component, which surface can be roughened by etching, can be obtained. An alloy of niobium with at least one element selected from the group consisting of Groups 3 to 16 by the group number of the periodic table is preferred. This alloy foil is etched, whereby an etched foil having an etching magnification of about 50 times or more and containing pores having an average pore size of about 0.05 to about 3 mum to the depth corresponding to at least about 5% or more of the foil thickness can be obtained. A capacitor is fabricated from this etched foil as at least one part electrode and a dielectric material interposed between this one part electrode and another part electrode, whereby a small-size and large-capacitance capacitor having good high-frequency performance can be produced. |
