The effects of sintered sample thickness on the dielectric properties of CaCu3Ti4O12 ceramics prepared at 1000-1100 °C in air

In this study, the relationship between dielectric properties and sintered sample thickness (d) (0.41-2.74 mm) of CaCu3Ti4O12 (CCTO) ceramics prepared at 1000-1100 degrees C in air was investigated. Compacted green ceramic bodies in varying weights and sintered at different temperatures were prepared to obtain ceramics with varying thicknesses. The samples were evenly polished on either surface, electroded and measured by a precision LCR meter at 20 Hz-1 MHz. The results showed that the epsilon' increased monotonically with increasing sintering temperature and indicated a linear relationship with d for samples sintered at >= 1040 degrees C, while the epsilon' for samples sintered at <= 1030 degrees C was barely affected. Complex impedance analysis showed that the rho(gb) was nearly constant with the change of d. The inverse effect of epsilon' and rho(gb) with d can also be observed for the gradual thickness reduction sample sintered at 1040 degrees C, confirming that the grain boundary plays a key role in the variation of dielectric properties for CCTO ceramics.