Regensburg 2004 – scientific programme
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DF: Dielektrische Festkörper
DF 5: Poster
DF 5.1: Poster
Wednesday, March 10, 2004, 14:30–18:00, Poster C
Well-ordered arrays of ferroelectric BaTiO3 and SrBi2Ta2O9 nanostructures grown by pulsed laser deposition — •Dietrich Hesse, Wenhui Ma, and Ulrich Gösele — Max-Planck-Institut für Mikrostrukturphysik Halle
Monolayers of monodisperse latex spheres of micron and submicron size were used as deposition masks to fabricate arrays of ferroelectric nanostructures by pulsed laser deposition (PLD). First, arrays of well-ordered BaTiO3 and SrBi2Ta2O9 amorphous structures were prepared on Nb-doped SrTiO3 (100) substrates (STO:Nb) by PLD at room temperature. These as-deposited structures were shown to have a pyramid-like shape with lateral sizes between 100 and 200 nm, forming a hexagonal pattern. Post-deposition annealing was used to crystallize these nanostructures. The ferroelectric properties of the crystalline nanostructures were investigated using scanning force microscopy in piezoresponse mode (PFM). Depending on material and size of the nanostructures, piezoelectric hysteresis loops of different shape and size were recorded, demonstrating that BaTiO3 and SrBi2Ta2O9 nanostructures of 100 to 200 nm lateral size have a remanent polarization and are switchable by an electric field, i.e. they are indeed ferroelectric.