Scanning near-field acoustic study of ferroelectric BaTiO₃ceramics

Ferroelectric materials have attracted attention in recent years because of the combination of these materials with integrated circuit technology. Although much effort has been made to develop new devices by the use of these materials, there is still much to do to understand the so-called domain effects at submicrometer or even in nanometer range. Although near-field acoustic techniques have achieved considerable progress in this respect recently, a complete understanding of physical effects in the near field of these techniques could not be completed solely by the use of one method, as both ferroelectric materials and near-field acoustic techniques are complicated in nature. A complementary study by two or more techniques will bring a new view to the analyses and characterization of ferroelectric materials and integrated devices. This paper will present complementary investigations on BaTiO 3 ceramics by the use of two non-destructive scanning near-field acoustic microscopy techniques on the identical areas of the same sample. A general model for both near-field acoustic techniques on ferroelectric BaTiO 3 is presented. Explanations of the results based on present theory will also be discussed in detail.