Abstract: Multilayer capacitors with have been made including a cadmium silicate flux by firing in a closed crucible at about 1100.degree. C. to provide a high K and smooth X7R coefficient of K with temperature, but tend to acquire a low insulation resistance in a high temperature life test under voltage. This problem was solved heretofore by the added step of a post-sinter anneal. However, the anneal step adds cost and further complexity to the manufacturing process.

Abstract: A ceramic powder mixture is made by combining from 96 to 98 mole percent of precursors of a stoichiometric barium zirconate titanate (BZT) wherein zirconium amounts to from 13.5 to 15.0 mole percent, and adding from 0.5 to 1.5 mole percent niobium or lanthanum, from 1.2 to 2.6 weight percent of a cadmium silicate sintering flux, essentially no lead, and from zero to 2 mole % of an alkaline earth metal to obtain in the powder mixture a ratio (A/B) of the large cations (A) to the small cations (B) in the range from 1.024 to 1.035. The mixture is calcined to obtain a powder comprised of agglomerates of essentially identical composition within the ranges given above. This powder of agglomerates may then be formed into a compact body that is sintered and fired to maturity at 1100.degree. C. to produce a mature dielectric ceramic body meeting the Y5V standard and having a dielectric constant greater than 10,000 at the Curie temperature.