NANOSIZE FERROELECTRIC PbTiO₃ STRUCTURES ONTO SUBSTRATES. PREPARATION BY A NOVEL BOTTOM-UP METHOD AND NANOSCOPIC CHARACTERISATION

ABSTRACT

This paper reports two different processes based on a novel method for the preparation of self-assembled PbTiO₃ nanostructures onto Pt coated (100) Si and SrTiO₃ substrates, involving chemical solution deposition (CSD), sol-gel chemistry and microemulsion mediated synthesis. The first one consists on the mixture of a highly diluted PbTiO₃ sol and a microemulsion, which is spun-coated onto the substrate. In order to improve the homogeneity of the thickness of the coating, in the second route, the microemulsion is firstly deposited onto the substrate and then onto this layer the sol is spun-coated. The deposits are dried under controlled conditions to enable the rearrangement of the micelles onto the substrate. Then, crystallisation of the PbTiO₃ nanostructures is carried out by Rapid Thermal Processing in air, at 923 K. These preparation procedures lead to nanosized and uniform PbTiO₃ structures. Piezoresponse force microscopy is used for the nanocharacterisation of these PbTiO₃ nanostructures.

Keywords:

• Nauostructure
• lead titanare
• bottom-up
• ferroelectricity

ACKNOWLEDGMENT

This work was supported by the Spanish Project MAT204–02014 and MAT2007-61409.