Dielectric ceramic composition having high dielectric constant

Abstract

Abstract PURPOSE:To obtain a ceramic composition having low dielectric loss, high insulation resistance and good temperature dependency of dielectric constant, by using a solid solution having a specific composition containing Bi, Pb, Fe, Nd, Nb and O as a component. CONSTITUTION:The objective ceramic composition is expressed by formula I (0.01<=x<=0.15; 0<y<=0.04). When x is <0.01, the insulation resistance is lowered and especially when x=0, the loss tangent becomes large. When y is >0.04, the Curie point becomes low and, accordingly, the radio of the maximum dielectric constant to the dielectric constant at 20 deg.C exceeds 1.3 within the temperature range of -25-+85 deg.C to spoil the practicability of the composition. The insulation resistance is low at y=0 and the dielectric loss tangent tends to become extremely large. The ceramic composition of the present invention is produced by forming a solid solution of a ferroelectric material of formula II with specific amounts of the compound of formula II and BiFeO3 having a perovskite structure with the same crystal structure as that of the ferroelectric material of formula II and sinterable at a low temperature.

Inventors

• 👤 Yoshio Yokoe
• 👤 Yusuke Tsutsumi

Bibliographic Details