Microwave Dielectric Properties of Li_2(M~(2+))_2Mo_3O_(12) and Li_3(M~(3+))Mo_3O_(12) (M = Zn, Ca, Al, and In) Lyonsite-Related-Type Ceramics with Ultra-Low Sintering Temperatures

摘要

In this work, the Li_2(M~(2+))_2Mo_3O_(12) and Li_3(M~(3+))Mo_3O_(12) (M = Zn, Ca, Al, and In) lyonsite-related structures were prepared using a solid-state reaction method. Single-phase lyonsite materials were formed for the following compositions Li_2Zn_2_ Mo_3O_(12), Li_3AlMo_3O_(12), and Li_(3)InMo_3O_(12) ceramics. Whereas, the Li_2Ca_2Mo_3O_(12) batched compositions produced Li_2MoO_4 and CaMoO_4 phases. All the four ceramics did not react with Ag and Al powders at their optimal sintering temperatures, which will permit the possibility of coflred electrodes with these metallurgies. The Li_2Zn_2Mo_3O_(12) ceramic can be sintered at 630℃ with a relative permittivity of 11.1, a Q ×/ value of ~70000 GHz, and a temperature coefficient of -90 ppm/℃ at 14.6 GHz. The Li_3AlMo_3O_(12) ceramic sintered at 570℃ has a relative permittivity of 9.5, a Q ×/value of ~50000 GHz, and a temperature coefficient of —73 ppm/℃ at 14.1 GHz. The Li_3InMo_3O_(12) ceramic sintered at 630℃ has a relative permittivity of 9.8, a Q x/value of ~36000 GHz, and a temperature coefficient of -73 ppm/℃ at 15.0 GHz. These ceramics are a good candidate for the expanding family of ultra-low temperature coflred ceramic technologies, for filter and substrate applications at the high-frequency range.