Bendable and transparent barium titanate capacitors on plastic substrates for high performance flexible ferroelectric devices

This article describes a fabrication procedure of high performance flexible ferroelectric materials supported on plastic substrates and the characterization of BaTiO₃ thin films on flexible substrates. Ferroelectric BaTiO₃ thin film was deposited using radio-frequency magnetron sputtering on a Pt/Ti/ SiO₂ / (100) Si substrate and annealed at 700°C for crystallization. The metal-insulator (BaTiO ₃) -metal structure was successfully transferred onto flexible substrates by the standard microfabrication and soft lithographic printing methods after removing the underlying sacrificial TiO₂ layer by buffered oxide etchant etching. The dielectric constant of the BaTiO₃ thin films on the flexible substrate was comparable with that on a bulk Si substrate. No significant change in dielectric constant was observed upon bending with various radii and debending.