부산대학교 도서관

In this work, the dielectric properties of Zn2+ doped CaCu3Ti4.1@4.2O12 (0 ≤ x ≤ 0.1) ceramics were investigated. A giant dielectric constant (ε′ ~ 8955–20639) and very low loss tangent (tanδ ~ 0.005–0.015) with an excellent temperature coefficient (Δε′ less than ± 15% over a temperature range of ~ − 60–180 °C) were achieved in CaCu2.90Zn0.10Ti4.1O12 and CaCu2.95Zn0.05Ti4.2O12 ceramics sintered at 1080 °C and 1100 °C for 8 h. The very low tanδ and excellent Δε′ obtained in these ceramics was due to a very high grain boundary resistance (Rgb), caused by the high density of grains and the presence of a TiO2-rich phase at the GBs. These excellent dielectric properties suggest a potential application for use in high temperature X7R and X8R capacitors. It was found that the tanδ values decreased with increasing sintering temperature due to an increase in a TiO2-rich phase. Nonlinear characteristics were observed in all ceramics, with significant enhancements in the nonlinear coefficient (α) and breakdown field (Eb) due to Zn2+doping. The best dielectric properties, ε′ (17598), tanδ (0.005), α (13.10) and Eb (5401.70 V·cm−1), with excellent-Δε′ (− 60–190 °C), were achieved in a CaCu2.95Zn0.05Ti4.2O12 ceramic sintered at 1100 °C for 8 h.