AC Complex Impedance Analysis of Doped Strontium Titanate Multifunctional Ceramics

Doped SrTiO3 capacitor-varistor multifunctional ceramics were fabricated by a single sintering process. AC complex impedance analysis was performed to investigate electrical features of grains and grain boundaries for both as-reduced ceramic and reoxidized ceramics. The results showed that the as-reduced ceramic exhibited inductive response at high frequencies above 2 MHz, which is attributed to the contribution of electron behavior in semiconducting grains. The high frequency inductive response disappeared in impedance plots of reoxidized ceramics.