Nonferroelectric epitaxial Sr–Bi–Ta oxide thin film with a high dielectric constant

Two kinds of epitaxial Sr–Bi–Ta oxides were grown on La0.5Sr0.5CoO3(001)/LaAlO3(001) substrates by pulsed laser deposition. At a temperature higher than 650 °C, c-axis oriented SrBi2Ta2O9 films could be deposited epitaxially. At 550 °C, an epitaxial film with a cubic fluorite-like phase could be grown. Although the film with the cubic phase does not show ferroelectric properties, it has good electrical properties which are suitable for high capacitance applications.