Ferroelectric films: nonlinear properties and applications in microwave devices.

Dielectric properties (epsilon, tan delta) of single crystal SrTiO3 (STO) films at microwave frequencies (3Ghz and 10GHz) and low frequency (1MHz) were under investigation. The intermodulation distortion measurement at frequency 2 GHz were carried out in microstrip resonator containing STO film planar capacitor. Formulas required to choose the most suitable ferroelectric materials and to design the tunable microwave devices (filters phase-shifters) are derived. Phase-shifter based on STO films with figure of merit 70 deg/1 dB operating in the frequency range (9.2 - 10.2)GHz at T = 77 K is presented.