Polarization imprint and size effects in mesoscopic ferroelectric structures

Piezoresponse scanning force microscopy measurements performed on lead zirconate titanate mesoscopic structures revealed a negative shift of the initial piezoelectric hysteresis loop. The shift is dependent on the size of the structure and is most probably due to the pinning of ferroelectric domains at the free lateral surface and ferroelectric-electrode interface. Considering a simple model, the thickness of the pinned domain layers is found to be about 15 and 70 nm at the ferroelectric-electrode interface and lateral free surface, respectively. (C) 2001 American Institute of Physics.