Preparation and characterization of (Ba, Sr)TiO 3 thin films using interdigital electrodes

Abstract

Apart from conventional parallel plate capacitors, the coplanar capacitor is another useful structure for ferroelectric film-based devices. In this work, barium strontium titanate (BST) thin film-based interdigital capacitors were prepared under different conditions. The relative permittivity of the films were extracted using a program developed based on Gevorgian’s model. It is found that the annealing temperature has significant influence on the relative permittivity. The higher the annealing temperature, the larger the relative permittivity. Meanwhile, the relative permittivity of BST film is found to increase with the film thickness. All these phenomena are consistent with that in BST film-based parallel plate capacitors, indicating that the processing–property relationship that was obtained in ferroelectric film-based parallel plate capacitors is a good reference for the study and development of novel ferroelectric film-based coplanar devices.