Heterolayered ferroelectric thin films and methods of forming same

摘要

Heterolayered thin films having ferroelectric/piezoelectric layers of alternating crystal structures and methods of their preparation are provided. In the ferroelectric/piezoelectric thin film, a first layer has a rhombohedral crystal structure and a second layer adjacent the first layer has a tetragonal crystal structure. The layers have a (100) preferred orientation with alpha-axis normal to the surface of the film. The first layer can be a Zr-rich lead ziroconate titanate layer (e.g., PbZr_0.8Ti_0.2O₃) and the second layer can be a Ti-rich PZT layer (e.g., PbZr_0.2Ti_0.8O₃). Heterolayered ferroelectric/piezoelectric thin film comprising a plurality of such first and second layers in alternating sequence exhibits particularly improved electrical properties.