Niobium capacitor and method of manufacture thereof

Abstract

A capacitor having a large capacity per unit weight and good LC characteristics is provided, which includes two electrodes and a dielectric interposed between the two electrodes, and the dielectric has a two-layer structure having a first layer predominantly containing niobium oxide NbOX (X=2.5) and a second layer predominantly containing 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 contains partially nitrided niobium, and more preferably partially nitrided niobium prepared by partially nitriding a niobium sintered body.

Dependencies are inferred from the claim text.