Device miniaturization poses not only technological and manufacturing challenges, it also requires the understanding of the phenomena occurring at nanoscale in condensed matter and at the involved interfaces. Herein, the authors present a summary of their results in fabricating and understanding the properties of ultrathin films and nanometer-size dots of ferroelectric perovskite and layered-perovskite oxides. (C) 2009 American Vacuum Society. [DOI: 10.1116/1.3025907]