Microwave dielectric properties of (ABi)1/2MoO4 (A = Li, Na, K, Rb, Ag) type ceramics with ultra-low firing temperatures

A series of (ABi)(1/2)MoO4 (A = Li, Na,K, Rb, Ag) compositions were studied in regard to the sintering behavior, phase composition, microwave dielectric properties and chemical compatibility with silver and/or aluminum for electrodes. All the (ABi)(1/2)MoO4 (A = Li, Na, K. Rb, Ag) ceramics could be sintered below 700 degrees C with relative densities above 93%. Whereas the (KBi)(1/2)MoO4 ceramic can be sintered to a high density at around 630 degrees C/2 hrs with a relative permittivity similar to 37,a Qf value of 4000 GHz and a temperature coefficient of resonant frequency (TCF) similar to +117 ppm/degrees C. Furthermore, from the XRD analysis of co-fired ceramics, the (KBi)(1/2)MoO4 ceramic reacts with silver but not with aluminum at its densification temperature. The (ABi)(1/2)MoO4 (A = Li, Na, K, Rb, Ag) type ceramics can all be considered into the new field of ultra-low temperature co-firing dielectrics for multilayer applications. (C) 2011 Elsevier B.V. All rights reserved.