High-Q (Na1-xAgx)2WO4 (x = 0.1, 0.2) ceramics with ultra-low sintering temperature

Abstract

The solid solution (Na1-xAgx)2WO4 (x = 0.1, 0.2) ceramics with ultra-low sintering temperatures were prepared by a modified solid-state reaction method. Through introducing Ag+ substitution at the Na+-site, the sintering temperature of the (Na1-xAgx)2WO4 ceramics have been lowered from 565℃ to 510–520℃, while their dielectric lose is still keeping low. The (Na0.9Ag0.1)2WO4 ceramic can be sintered well at 520℃ with a permittivity of 5.8, a Q × f value of 97 600 GHz and a temperature coefficient of −70 ppm/℃ at 12.6 GHz. After being sintered at 510℃, the (Na0.8Ag0.2)2WO4 ceramic possesses the best properties with a permittivity of 6.1, a Q × f value of 70 600 GHz and a temperature coefficient of −72 ppm/℃ at a frequency of 12.5 GHz. Due to the excellent dielectric properties, the (Na1-xAgx)2WO4 (x = 0.1, 0.2) ceramics are potential candidate for Low-Temperature Co-fired Ceramics (LTCC) applications.