Enhanced in-plane ferroelectric polarizations with low in-plane leakage currents in Ca-doped SrBi 2 Ta 2 O 9 textured ceramics

Abstract The Aurivillius-phase layered material SrBi2Ta2O9 possesses an extremely low leakage current (~10−9 A·cm−2) along the out-of-plane direction with in-plane ferroelectricity, which brings difficulties in achieving high ferroelectric performance and low leakage current simultaneously in randomly oriented ceramics. Here, highly textured SrBi2Ta2O9 ceramics with a texture degree of f = 0.985 are prepared using templated grain growth (TGG) technology with a tape-casting method. The in-plane remnant polarization achieves 15.83 μC·cm−2, which is increased by 197% compared with that of the SrBi2Ta2O9 randomly oriented ceramic. Doping Ca is found to reduce the in-plane leakage current density to J = 5.924×10−7 A·cm−2, which is attributed to the increased electronic band gap. This research presents an effective route for developing high-performance SrBi2Ta2O9-based ferroelectric devices.