  Strong coupling between electrical and mechanical phenomena and the presence
of switchable polarization have enabled applications of ferroelectric materials
for nonvolatile memories (FeRAM), data storage, and ferroelectric lithography.
Understanding the local functionality of inorganic ferroelectrics including
crystallographic orientation, piezoresponse, elasticity, and mechanisms for
polarization switching, requires probing material structure and properties on
the level of a single ferroelectric grain or domain. Here, I present recent
studies on electromechanical, mechanical, and spectroscopic characterization of
ferroelectric materials by Scanning Probe Microscopy. Three-dimensional
electromechanical imaging, referred to as Vector Piezoresponse Force
Microscopy, is presented. Nanoelectromechanics of PFM, including the structure
of coupled electroelastic fields and tip-surface contact mechanics, is
analyzed. This establishes a complete continuum mechanics description of the
PFM and Atomic Force Acoustic Microscopy imaging mechanisms. Mechanism for
local polarization switching is analyzed. The hysteresis loop shape is shown to
be determined by the formation of the transient domain below the tip, the size
of which increases with the tip bias. Spectroscopic imaging that allows
relevant characteristics of switching process, such as imprint bias, pinning
strength, remanent and saturation response, is introduced. Finally, resolution
in PFM and vector PFM imaging of local crystallographic and molecular
orientation and disorder is introduced.
