Chemical Synthesis of Multilayered Nanostructured Perovskite Thin Films with Dielectric Features for Electric Capacitors

We report a simple sol–gel method for the preparation of multilayered hybrid thin films composed of nanostructured SrTiO3 (STO) and BaTiO3 (BTO) layers. A nanoporous thin film of STO is prepared by the spin-coating method on Si/SiO2/Ti/Pt substrate. When the BTO is processed, the BTO is crystallized between STO crystal pores. A significant strain field is induced on the interface between the STO and BTO surfaces. The concave shape of the nanopores could enable the realization of a highly strained interfacial heterostructure composed of STO/BTO. Compared to nanostructured STO, BTO, and bilayer STO/BTO films, multilayered STO/BTO films show the highest dielectric constant and a high Curie temperature (Tc) at around 280 °C, which is suitable for electric capacitor applications.