Effects of Dy substitution for Y on microwave dielectric properties of High-Q R2O3-BaO-ZnO (R=Y and Dy) system

The (Y2−xDyx)BaZnO5 solid solutions were synthesized and studied, this paper focused on the relationships between the crystal structure and the improvements in temperature coefficients of resonant frequency (τf) caused by Dy substitution for Y. The dielectric constants (εr) were slightly increased with increasing the composition x; this result was attributed to the increase in the ionic polarizabilities caused by Dy substitution for Y. The quality factors (Q·f) were extremely decreased from 165,500 to 29,600 GHz with increasing the composition x. The τf values were increased from −44.5 to −1.6 ppm/°C, whereas the temperature coefficients of the dielectric constant (τε) varied from positive to negative values.