Material Development of High Dielectric Constant (Sr, Pb)TiO₃ Series Ceramics

Abstract

Barium titanate series dielectric ceramics, as an indispensable material for capacitor in electronic circuit, has been used in large quantities. Since the material is ferroelectricity, however, it has problems for high voltage use of power electric field, which are to let change capacitance sharply caused by its voltage depnedent characteristic, and to be unable to have long life caused by the material's peculiar property of high dielectric loss. It was already reported that the present material, which had been developed from (Sr, Ba)TiO₃ series ceramics for the elimination of problems, was remarkable for showing paraelectric characteristics and was moreover high dielectric constant. Furthermore, a new material with a higher dielectric constant than the present, has been required for the same purpose of power electricity. The new material, which fulfills the requirement, has been developed from (Sr, Pb)TiO₃ series ceramics, showing its dielectric constant of 2800. The explanation of the anthor's fundamental way of thinking in developing the new materials, and the study on the electric characteristics and the microstructure of the material are discussed in this paper.