High electromechanical strain and enhanced temperature characteristics in lead-free (Na,Bi)TiO-BaTiO thin films on Si substrates.

Here, we demonstrate the high electromechanical strain and enhanced temperature characteristics in the c-axis-oriented lead-free (Na,Bi)TiO-BaTiO (NBT-BT) polycrystalline thin film prepared on Si substrates by rf magnetron sputtering. The effective transverse piezoelectric coefficient, e, estimated from the electromechanical strain measured under high electric field, reaches a high level of -12.5 C/m, and is comparable to those of conventional Pb(Zr,Ti)O films.

Temperature dependence of dielectric permittivity of perovskite-type artificial superlattices.

Perovskite-type BaTiO(3)/SrTiO(3) (BTO/STO) artificial superlattices were fabricated by the molecular beam epitaxy method. The X-Ray diffraction (XRD) profiles and reflection, high-energy, electron diffraction (RHEED) oscillations during the growth of superlattices indicated that crystalline orientation toward [001] direction and two-dimensional layer-by-layer growth were achieved. The capacitance, dielectric loss tangent, and complex admittance were measured up to 145 degrees C and up to the frequency of 100 MHz with the microplaner interdigital electrodes.