Dielectric Properties of Pb-Based Perovskite Substituted by Ti for B-site at Microwave Frequencies

Abstract

Substitutions of B-sites by Ti in several Pb-based perovskite ceramics that had high relative permittivities (ε r ), high Q values, and small temperature coefficients of resonant frequency (τ f ) were studied in order to control ε r and τ f independently. It was found that relative permittivities with near-zero τ f in (Pb, Ca)(Zr, Ti)O 3 , (Pb, Ca){(Fe 1/2 Nb 1/2 ), Ti}O 3 , and (Pb, Ca){(Mg 1/3 Nb 2/3 ), Ti}O 3 systems could be controlled in the ε r regions lower than 105, 95, and 70, respectively. All these systems had sufficiently high Q values. They are applicable to resonant devices for mobile communications.