Preparation and properties of soft ferroelectric BaTiO/sub 3/ thin film by sol-gel process

Soft ferroelectric BaTiO/sub 3/ ceramics having a very low coercive field of 40 V/mm were prepared by substituting 9 mol% Hf-Zr for Ti-site of BaTiO/sub 3/. Accordingly, the soft ferroelectric materials have great potential for applications in ferroelectric thin-film devices due to a relatively low coercive field, which allows easy switching of the ferroelectric domains. In addition, sol-gel-derived soft ferroelectric BaTiO/sub 3/ thin films were prepared by spin coating. The microstructure and electrical properties of the films were measured on Pt and Pt/Ti/SiO/sub 2//Si[100] (hereinafter, "PS") substrates. The room-temperature coercive field, Ec, and remanent polarization, Pr, for the 870-nm-thick soft ferroelectric BaTiO/sub 3/ thin film prepared on platinized silicon substrate at 700/spl deg/C were determined to be 25 kV/cm and 7 /spl mu/C/cm/sup 2/, respectively. Those for the film, prepared on the Pt substrate at 950/spl deg/C were 18 kV/cm and 9 /spl mu/C/cm/sup 2/, respectively.