Highlight: Nanoscale piezoresponse of ferroelectric domains
The first fundamental studies of the dependence of ferroelectric domain configuration and switching behavior on the shape of epitaxial BiFeO3 (BFO) nanostructures has been reported by users from Northwestern University, Korea Advanced Institute of Science & Technology, and Argonne’s Materials Science Division working collaboratively with CNM’s Nanofabrication & Devices Group.
The nanostructures were produced by growing BFO films on SrRuO3 (SRO) (001) oriented electrode layers on single-crystal SrTiO3 (STO) (100) substrates. Shapes were fabricated using rf-magnetron sputtering deposition followed by focused ion-beam lithography.
Domain configuration was investigated using piezoelectric force microscopy, revealing that the square-shaped nanostructures have a single variant domain configuration, whereas the round-shaped nanostructures exhibit seven variants of domain configuration.
The results have implications for the development of nanocapacitors for gigabyte to terabyte nonvolatile ferroelectric memories.
More information: S. Hong, J. Klug, M. Park,A. Imre, M. Bedzyk, K. No, A. Petford-Long, and O. Auciello, J. Appl. Phys., 105, 061619 2009