Complex electrical (impedance/dielectric) properties of electroceramic thin films by impedance spectroscopy with interdigital electrodes

• Published in: Thin solid films 2007-04, Vol.515 (11), p.4588-4595
• Main Authors: Kidner, N.J., Meier, A., Homrighaus, Z.J., Wessels, B.W., Mason, T.O., Garboczi, E.J.
• Format: Article
• Language: English
• Subjects: Barium titanate films; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric properties of solids and liquids; Dielectric, piezoelectric, ferroelectric and antiferroelectric materials; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; Farnell; Impedance spectroscopy; Interdigital electrodes; Permittivity (dielectric function); Physics
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2006.11.038

The complex electrical properties of isotropic, electroceramic thin films can be measured with interdigital electrodes, analyzed by impedance spectroscopy (IS). A periodic two-dimensional film/interdigital electrode (IDE) structure was simulated by finite-difference numerical method and a generalized model was developed to characterize the electrical properties of thin films. Variable frequency simulations showed that the film/IDE system can be modeled as a parallel resistor–capacitor equivalent circuit. Equations were developed to extract from the equivalent circuit's fitted resistance and capacitance, the materials properties of the thin film, both conductivity and permittivity. The electrical properties of a polydomain BaTiO 3 film grown on a MgO substrate were measured with an IDE structure by IS to demonstrate how the methodology can be readily used.