MICROWAVE DIELECTRIC PROPERTIES OF Mn:BST AND PST THIN-FILMS

ABSTRACT In this study, we characterized nano-structured Mn doped BST thin-films fabricated using a pulsed laser deposition process at the University of Houston, and PST thin-films fabricated using MOCVD at the Arizona State University. Coplanar waveguide test structures were used for experimental evaluation of the dielectric properties of the BST and PST thin-films fabricated on MgO and saphire substrates respectively. The test structures were fabricated on bare substrates as well as on the thin-film test samples for determination of attenuation and phase constants with and without the ferroelectric thin-films. The ϵfilm for the Mn:BST film was approximately 1200 over the frequency range of 15–30 GHz with the loss-tangent averaging to 0.033. The PST thin-film on sapphire substrate had a zero-bias relative dielectric constant of 200 and the loss-tangent was estimated to be 0.05 over the measured frequency range of 10 to 18 GHz.