Effect of Sn4+ doping on the dielectric and nonlinear J–E properties of CaCu3Ti4.1O12 ceramics with a slight titanium excess for X9R capacitors

Abstract

Sn4+ doped CaCu3Ti4.1−xSnxO12 (x = 0.00, 0.05, and 0.10) ceramics were prepared using a one-step polymer pyrolysis method. Variation of Δε′\u2009<\u2009±\u200915% over a temperature range of −\u200960 to 210 °C, very low tanδ ~ 0.009–0.012 and giant-ε′ ~\u20096685–14,194 at 30 °C and 1 kHz were achieved in ceramics with x = 0.05 and 0.10 sintered at 1080 °C for 7 h. Furthermore, tanδ values of less than 0.03 and Δε′ < ±\u200910% over wide temperatures range of −\u200960 to 150 °C and −\u200960 to 200 °C were obtained in each of the ceramics. Both ceramics are promising candidate materials for X9R capacitor and X-P capacitor applications. The increase of grain boundary resistance (Rgb) with increasing Sn4+ content in the presence of a TiO2 phase are suggested to play an important role in extending Δε′ < ±\u200915% and tanδ\u2009<\u20090.05 over a wider temperature range.