Microwave Dielectric Properties of SrRE4Si3O13 (RE=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Tm, Yb, and Y) Ceramics

作者:Thomas Sherin; Sebastian Mailadil Thomas*
来源:Journal of the American Ceramic Society, 2009, 92(12): 2975-2981.
DOI:10.1111/j.1551-2916.2009.03326.x

摘要

The apatite type SrRE4Si3O13 (RE=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Tm, Yb, and Y) ceramics have been prepared by the conventional solid-state ceramic route. The phase purity and surface morphology of the sintered ceramics were studied using X-ray diffraction and scanning electron microscopy methods. These materials showed poor sinterability and was improved by the addition of a small weight percentage of zinc borosilicate glass. The microwave dielectric properties of these materials were studied for the first time. SrRE4Si3O13 ceramics have a low relative permittivity (epsilon(r)) in the range 9-16, a Q-factor (Q(u) x f) upto 26 000 GHz and a low temperature coefficient of resonant frequency (tau(f)). The SrLa4Si3O13 ceramics possessed a high Q(u) x f of nearly 26 000 GHz but with a high negative tau(f) of -46 ppm/degrees C. The tau(f) of SrLa4Si3O13 ceramics was tuned by the addition of suitable amount of TiO2.

  • 出版日期2009-12