Vishay Intertechnology, Inc.

Vishay Sprague, Inc.

Eli Bershadsky

Reuven Katraro

John Bultitude

David Ben-Bassat

Dani Alon

Nissim Cohen

Marina Kravchik-Volfson

Marina Kravchik

A bulk capacitor includes a first electrode formed of a metal foil and a semi-conductive porous ceramic body formed on the metal foil. A dielectric layer is formed on the porous ceramic body for example by oxidation. A conductive medium is deposited on the porous ceramic body filling the pores of the porous ceramic body and forming a second electrode. The capacitor can then be encapsulated with various layers and can include conventional electrical terminations. A method of manufacturing a bulk capacitor includes forming a conductive porous ceramic body on a first electrode formed of a metal foil, oxidizing to form a dielectric layer and filling the porous body with a conductive medium to form a second electrode. A thin semi-conductive ceramic layer can also be disposed between the metal foil and the porous ceramic body.

Bulk capacitor and method

A dielectric ceramic composition has a dielectric constant, K, of at least 200 and a dielectric loss, DF, of 0.0006 or less at 1 MHz. The dielectric ceramic composition may be formed by sintering by firing in air without a controlled atmosphere. The dielectric ceramic composition may have a major component of 92.49 to 97.5 wt. % containing 60.15 to 68.2 wt. % strontium titanate, 11.02 to 23.59 wt. % calcium titanate and 7.11 to 21.32 wt. % barium titanate; and a minor component of 2.50 to 7.51 wt. % containing 1.18 to 3.55 wt. % calcium zirconate, 0.50 to 1.54 wt. % bismuth trioxide, 0.2 to 0.59 wt. % zirconia, 0.02 to 0.07 wt. % manganese dioxide, 0.12 to 0.35 wt. % zinc oxide, 0.12 to 0.35 wt. % lead-free glass frit, 0.24 to 0.71 wt. % kaolin clay and 0.12 to 0.35 wt. % cerium oxide. UHF antennas and monolithic ceramic components may use the dielectric ceramic composition.

Ceramic dielectric formulation for broad band UHF antenna

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Haifa, Israel

Eli Bershadsky