LAUSR

An approach to separate the metallic and dielectric losses in ferroelectric capacitors in all range of tuning under control dc voltages (Udc) is considered. The procedure is based on measurements of the dc voltage dependencies of microwave losses (tan δt(Udc)) and capacitance (C(Udc)) for a set of capacitors with similar layout but with different nominals. Linear extrapolation of tan δt(C) dependencies at different control dc voltages to C = 0 allows to evaluate the dielectric losses tan δd as a function of the control dc voltage. The procedure of separation was performed for a set of sandwich metal/(Ba0.5Sr0.5)TiO3/metal capacitors. Capacitors parameters were measured at a frequency of 2 GHz in a range of electric field strength in ferroelectric of E = (0 − 30) V/μm. The intrinsic commutation quality factor of BSTO film itself was estimated by the method proposed.