| abstract |
An electrolytic capacitor is disclosed which contains an anodically oxidized anode incorporating an additional metallic element. More specifically, the metallic element is incorporated in the valve metal pentoxide of the dielectric layer. In a particular embodiment, the insertion of the metallic element results in a niobium pentoxide dielectric containing closely packed units of O atoms, octahedral Nb 6 - and metal atoms ("A") serving as counter cations. The use of relatively small electropositive metal atoms ("A") helps to identify the tetrahedral (eg Al, Si, Ti, Mg or Mn), octahedral (eg Nb, V, Mg or Mn) and trigonal-bipyramidic (eg V, Nb) To fill crystal interstices. The stability of the capacitor leakage currents can be improved by varying this crystal structure. |