Domain imaging, polarization hysteresis, and switching in nano-size ferroelectric structures

A fundamental issue in the physics of ferroelectric memories and piezoelectric devices is to study how their properties scale with the size of the ferroelectric structure. In this work we present results concerning the ferroelectric behavior of structures with lateral sizes in the range 100 nm to 1 mum. The ferroelectric characterization was achieved using the piezoresponse mode of a scanning force microscope. 100 nm patterned PZT polycrystalline structures as well as 200 nm epitaxial SrBi2Ta2O9 grains exhibit distinct ferroelectric hysteresis loops. Fatigue measurements on 500 nm structures of PZT were also performed and are discussed.