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Ceramic capacitors, MIL style CK63, capable of operating at 200C, were manufactured from a fluorinated dielectric of which BaTiO3 was the predominant material, 87%, other materials being CaZrO3, 12.7%; Fe2O3, 0.1%; and Ce2O3, 0.2%. A low voltage, miniaturized, fluorinated capacitor, having a thin dielectric of the same composition as the CK63 capacitors, was also manufactured for 200C operation. Fluorination of a dielectric was accomplished by re-firing the matured dielectric in a fluoride atmosphere., See also AD-605 753.

The fluorinated dielectric has passed 2000 hours of life test at 200 C with no failures. The post life measurements of dissipation factor, capacitance and insulation resistance indicate little, if any, degradational effect of the 2000 hour test. The reliability of these capacitors appears to be outstanding. The molten glass apparently dissolves a portion of the silver electrode during the glass dipping operation. This results in a capacitance loss which can be easily compensated for during silver painting operation prior to glass encapsulation. The final encapsulant of silicone rubber provides an excellent protective envelope but does not contribute toward improved terminal strength properties. (Author)