Microwave characterization of thin ferroelectric films

A simple technique for characterization of dielectrics at high microwave frequencies is proposed and verified experimentally. The technique makes use of the measured impedance of a test structure. The latter is a simple capacitor, formed on the top of a substrate with an arbitrary number of dielectric/conductor layers and contains a material under test (MUT) layer with unknown loss tangent and dielectric constant. Assuming that all other layers are specified, a simple method is given to calculate RF impedance of such a structure enabling extraction of MUT properties.