Patent attributes
An electrolytic capacitor that contains an anodically oxidized anode that is incorporated with an additional metallic element is provided. More specifically, the metallic element is built into the valve metal pentoxide of the dielectric layer. In one particular embodiment, the addition of the metallic element results in a niobium pentoxide dielectric that contains closely packed units of O atoms, Nb6 octahedral, and metal atoms (“A”) that serve as counter cations. The use of relatively small electropositive metal atoms (A″) helps fill the tetrahedral (e.g., Al, Si, Ti, Mg, or Mn), octahedral (e.g., Nb, V, Mg, or Mn) and trigonal bipyramid (e.g., V, Nb) interstices of the crystals. The stability of capacitor leakage current may be improved by variation in this crystal structure.