Thermal stable microwave dielectrics

Thermally stable high dielectric constant ceramics are used in microwave technology as dielectric resonators, filters, microwave substrates, waveguides and antennas. The dielectric spectroscopy method, initiated from low frequencies and extended up to the far infrared range and applied at temperatures 10-1000 K, was used to study mechanisms of polarization. It was shown that nature of low loss microwave dielectrics thermostability is nanoscale clusters, electronic by their nature, with extremely low relaxation time. This mechanism provides thermal stability together with the low microwave loss (tan/spl delta//spl sim/10/sup -4/) with dielectric constant /spl epsiv//spl sim/100.