Structural, dielectric and ferroelectric study of (1−ϕ)(NBT–KNN)–ϕSBexT ceramics

• Synthesis of (1−ϕ)(NBT–KNN)–ϕSBexT (ϕ=0, 2, 4, 8, 12, 16 wt%) ceramic samples.
• Decrease of Tm with the increase of SBexT content.
• Retention of good ferroelectric properties.
• Pr, leakage current and polarization degradation decreased with increase of SBexT.
• Usefulness of the ceramic composites for the NVRAM applications.

(1−ϕ)(0.93 Na0.5Bi0.5TiO3–0.07K0.5Na0.5NbO3)-ϕSr0.8Bi2.15Ta2O9/(1−ϕ)(NBT–KNN)–ϕSBexT (ϕ=0, 2, 4, 8, 12, 16 wt%) ceramic samples were synthesized by conventional solid state reaction route. Secondary phases started developing for higher SBexT content in the (1−ϕ)(NBT–KNN)–ϕSBexT ceramic samples. Decrease of transition temperature (Tm) with the increase of SBexT content in (1−ϕ)(NBT–KNN)–ϕSBexT ceramics was attributed to the increase of internal stress. Remnant polarization (Pr), leakage current density and polarization degradation values reduced with the increase of SBexT content in (1−ϕ)(NBT–KNN)–ϕSBexT ceramic samples. Retention of good ferroelectric properties and enhancement of fatigue-free behavior with the incorporation of SBexT phase in (1−ϕ)(NBT–KNN)–ϕSBexT ceramic samples suggested their usefulness for ferroelectric memory applications.

Normalized polarization vs. number of cycles of (1−ϕ) (NBT–KNN)–ϕSBexT (ϕ=0, 2, 4, 8, 12, 16 wt%) ferroelectric ceramic composites measured at RT.Figure optionsDownload as PowerPoint slide