Characterization of microwave dielectric properties of ferroelectric parallel plate varactors

A procedure to accurately evaluate microwave dielectric properties of parallel plate varactors fabricated on a BST thin film deposited by pulsed laser deposition on a platinized silicon substrate is presented. The reliability of the high-frequency properties of dielectric thin films extracted from the measured reflection coefficient S11 is mainly limited by how accurately the parasitic effects are eliminated from the measured data. The parasitic effects were effectively removed on evaluating the thin-film dielectric properties based on the good agreement between the experimental results measured with the parasitic model and the computer simulation data.