Domain configuration and interface structure analysis of sol-gel-derived PZT ferroelectric thin films

The domain configuration and interfacial structure of sol-gel-derived PZT t hin films were evaluated using atomic force microscopy and x-ray photoelect ron spectroscopy. Microstructure and ferroelectric property investigation o f the PZT thin films under repeated a.c. field suggests that microcracks ma y be the major cause for ferroelectric fatigue. The intersection of 90 degr ees domain walls, where the concentration of stress occurs, is likely to be the origin of microcracks. In addition, the entrapment of defects at domai n walls, grain boundaries and/or PZT/electrode interface due to relatively lower potential energy at these sites results in an internal field with a d irection opposite to the applied field, which weakens the electric field in tensity in the PZT thin films. A fraction of the domains is pinned and fina lly results in polarization fatigue of the PZT thin films. Copyright (C) 20 01 John Wiley & Sons, Ltd.