Impact of Lattice Strain on Structure and Electric Properties of Alkaline-Niobate Thin Films
The solid-solution potassium-sodium-niobate (K,Na)NbO3 represents a class of materials with different functional properties. While NaNbO3 is antiferroelectric at room temperature, the addition of small amounts of K results in a solid-solution with ferro-/piezoelectric properties. However, strictly speaking, this only applies to bulk materials.
In epitaxial films, lattice strain is easily incorporated by the use of lattice mismatched substrates. This causes that NaNbO3 typically exhibits ferroelectric properties. But moreover, it enables an intentional tuning of the electrical properties of oxide thin films if the correlation between lattice strain and phase formation is known. In this talk, this will be discussed for tensile and compressive lattice strain for epitaxial NaNbO3 and (K,Na)NbO3 films grown on different rare-earth scandate substrates by metal-organic vapor phase epitaxy (MOVPE).
Jutta Schwarzkopf did her doctorate in physics at Fritz-Haber-Institut in Berlin and at Technische Universität Berlin in 1997 for a thesis entitled “Surface morphology of epitaxially grown GaAs surfaces”. She was postdoctoral researcher at Helmholtz-Zentrum Berlin (formerly: Hahn-Meitner-Institute) where she performed homoepitaxial growth of Silicon films for photovoltaic applications. Since 2004 she is senior scientist and since 2018 section leader at Leibniz-Institut für Kristallzüchtung in Berlin. Her research interests are the epitaxial growth and characterization of oxide thin films by MOVPE and PLD as well as the strain and defect engineering in perovskite thin films.