A 310 degrees K-band phaseshifter using tunable BaSrTiO3 interdigitated capacitors
Résumé
BaSrTiO/sub 3/ thin films were deposited by low-cost sol-gel techniques and exhibit relative permittivity of 300 and loss tangent of 0.012 with a roll off above 5 GHz. Subsequently the films were used for fabricating coplanar waveguide phaseshifters using tunable finger-shaped capacitors. A 310/spl deg/ phaseshift was thus obtained at 30 GHz and 35 V of tuning voltage with 3.6 dB of insertion loss yielding a figure of merit of 85/spl deg//dB.