NIOBIUM CAPACITOR AND METHOD OF MANUFACTURE THEREOF

摘要

A capacitor having a large capacity per unit weight and good LC characteristics is provided, which comprises two electrodes and a dielectric interposed between the two electrodes, and the dielectric has a two-layer structure comprising a first layer predominantly comprised of niobium oxide NbOx (X = 2.5) and a second layer predominantly comprised of a mixture of niobium oxide NbOx (X = 2.5) and niobium oxide NbOx (X = 2.0). Preferably, both the first and second layers contain 90 weight % or more of NbOx, and the molar ratio of NbOx (X = 2.5) to NbOx (X = 2.0) in the second layer is 1:4 to 4:1, and the proportion of the first layer in the two-layer structure is 0.01 to 10% by volume. One of the electrodes preferably comprises partially nitrided niobium, and more preferably partially nitrided niobium prepared by partialy nitriding a niobium sintered body.