Preparation of BaTiO3-based thick films with c-axis-preferred orientation using screen printing

Pb(Zr,Ti)O3 and related materials have been lauded for their piezoelectric properties, but their toxicity has driven the search for alternative materials with the same high performance in electronic devices. Among these, BaTiO3-based materials are regarded as excellent substitutes. Using a screen printing method, in this study, we prepare BaTiO3 thick films on ZrO2 stabilized with 3 mol % Y2O3 (YSZ) or MgO ceramics with Pt bottom electrodes. BaTiO3 thick films prepared on YSZ and MgO substrates preferentially oriented along the a- and c-axes, respectively. The remanent polarization Pr of the MgO-based films was higher than that of the YSZ-based films (10.8 µC/cm2 vs 6.5 µC/cm2) and comparable to that of BaTiO3 bulk ceramics. Thermal expansion measurements of BaTiO3, YSZ, and MgO ceramics suggested that compressive stress was exerted on the BaTiO3 thick films, causing them to orient along the c-axis. (Ba0.92Ca0.08)(Ti0.975Zr0.025)O3 thick films were also prepared on the YSZ and MgO substrates and showed similar preference for the c-axis on MgO. However, the remanent polarization of (Ba0.92Ca0.08)(Ti0.975Zr0.025)O3 thick films prepared on MgO was greater than that of bulk ceramics (14.9 µC/cm2 vs 11.0 µC/cm2).