Unusual Curie Point Independence of Thickness and Interfacial Properties for Perfectly (111)-Oriented Ba0.6Sr0.4TiO3 Thin Films
Abstract:This study investigated the variations in the permittivity with film thickness and measurement temperature of perfectly (111)-oriented Ba0.6Sr0.4TiO3 thin films with thicknesses ranging from 45 to 800 nm, which were prepared by RF magnetron sputtering on Pt/TiOx/SiO2/Si substrates. All the films showed elongations in the lattice parameter, suggesting the presence of residual strains but which were insensitive to the film thickness. The temperature-dependent measurement of the permittivity revealed an unusual Curie point independent of thickness, about 305±5 K, where the phase transition appeared frustrated. The thickness-dependent permittivity at a given temperature was explained by using the interfacial intrinsic low-permittivity layer model reported previously.
Document Type: Research Article
Affiliations: 1: Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China 2: IEMN-DOAE-MIMM Team, UMR CNRS 8520, Bat. P3, Cité scientifique, Villeneuve d'Ascq, 59655 Lille, France
Publication date: September 1, 2010