Study of three-component ferroelectric perovskite superlattices

Abstract

We fabricated the three-component ferroelectric superlattices consisting of alternating layers of SrTiO₃, BaTiO₃ and CaTiO₃ (SBC) with variable interlayer thickness on Pt(111)/TiO₂/SiO₂/Si(100) substrates by pulsed laser deposition. The fabrication of superlattice structures was confirmed by the presence of satellite reflections in x-ray diffraction analysis and a periodic concentration of Sr, Ba and Ca throughout the film in depth profile of secondary ion mass spectrometry analysis. The surface morphology evolutions of the films with different thickness of each layer by varying laser pulse shots were investigated by Scanning Electron Microscopy and Atomic Force Microscopy. The P_r (remnant polarization) and P_s (saturation polarization) of SBC superlattice with 10 nm individual layer thickness were found to be around 4.5 µ C/cm² and 27 µ C/cm² respectively.