(111) Twins in BaTiO₃ Thin Films Deposited by RF Magnetron Sputtering

Abstract

Polycrystalline BaTiO 3 thin films were prepared by rf magnetron sputtering and twin structures in the thin films were investigated using a transmission electron microscope. (111) twin boundaries were found in the thin films with thicknesses of 2100 and 10000 Å. Not only single twin boundaries but (111) twin lamellae with a very narrow width of ≈1 nm were observed in thin films of both thicknesses. This result suggested that the twin lamellae would be stable although the interfacial energy appeared to be much higher than single twin boundaries. A correlation between twin lamella width and grain size was also found.