Scanning probe microscopy of domains and domain walls in sol-gel PbTiO3 thin films

We report results on ferroelectric domain and domain-wall observation in sol-gel PbTiO3 thin films using scanning probe microscopy. By taking the phase and amplitude image of the local domain piezovibration separately, more information is given to interpret the domain contrast owing to the a domain and different crystallographic orientations. Particularly, the a-c and c-c domain walls appear as a transition region and a dark region in the amplitude image, respectively, and the corresponding thickness is estimated to be 70 and 8 nm. A torsion vibration model is proposed to describe the tip vibration at the c-c domain wall, which results in the dark contrast correspondingly. (C) 2001 American Vacuum Society.