LARGE AREA THIN FILM CAPACITORS ON METAL FOILS AND METHODS OF MANUFACTURING SAME

摘要

Method of making a dielectric on a metal foil is disclosed, and a method of making a large area capacitor that includes a dielectric on a metal foil obtained from the method is disclosed. A dielectric precursor layer and the base metal foil are prefired at a prefiring temperature in the range of 350 to 650°C in a moist atmosphere that also comprises a reducing gas. The prefired dielectric precursor layer and base metal foil are subsequently fired at a firing temperature in the range of 700 to 1200°C in an atmosphere having an oxygen partial pressure of less than about 10-6 atmospheres to produce a dielectric. The area of the capacitor made according to the disclosed method may be greater than 10 mm2, and subdivided to create a multiple individual capacitor units that may be embedded in printed wiring boards. The dielectric is typically comprised of crystalline barium titanate or crystalline barium strontium titanate.