Nanoscale reconstruction of surface crystallography from three-dimensional polarization distribution in ferroelectric barium-titanate ceramics

The three-dimensional orientation of polarization vectors at the surface of ferroelectric barium-titanate (BaTiO3) ceramics is evaluated using voltage-modulated scanning force microscopy (SFM). By applying an ac voltage to the conductive SFM tip, we measure the relative amount of the three orthogonal components P-x, P-y, and P-z, of the polarization vector at any surface point. The measured polarization orientation together with the actual domain-wall orientation allows a precise reconstruction of the crystallographic orientation of the investigated grains down to a 40 nm resolution. Excellent agreement is obtained when comparing this orientation with the crystallographic reconstruction revealed by etch patterns from the sample surface topography. We show that the surface topography manifests a domain structure, which was present in the past, while the actual ferroelectric domain configuration is revealed by the modulation technique. (C) 1999 American Institute of Physics. [S0003-6951(99)05502-3].