High performance low cost ferroelectric phase shifters designed for simple biasing

A novel approach in ferroelectric phase shifters design using Ba_xSr_1-xTiO₃ (BSTO) films in a multilayer dielectric coplanar waveguide structure is described. By including a low loss dielectric layer (SiO₂) between the coplanar waveguide conductors and the ferroelectric material in conjunction with a via to allow the signal conductors to contact the ferroelectric layer to employ biasing, significant reduction in insertion loss can be achieved in conjunction with a three fold increase in figure of merit (/dB) compared to the case with direct metallization on the ferroelectric layer.