Microwave dielectric properties of novel temperature stable high Q Li2Mg1-xZnxTi3O8 and Li2A1-xCaxTi3O8 (A = Mg, Zn) ceramics

The Li2Mg1-xZnxTi3O8 (x = 0-1) and Li(2)A(1-x)Ca(x)Ti(3)O(8) (A = Mg, Zn and x = 0-0.2) ceramics are synthesized by solid-state ceramic route and the microwave dielectric properties are investigated. The Li2MgTi3O8 ceramic shows epsilon(r) = 27.2, Q(u) x f = 42,000 GHz, and tau(f) = (+)3.2 ppm/degrees C and Li2ZnTi3O8 has epsilon(r) = 25.6, Q(u) x f = 72,000 GHz, and tau(f) = (-)11.2 ppm/degrees C respectively when sintered at 1075 degrees CA h. The Li2Mg0.9Zn0.1Ti3O8 dielectric ceramic composition shows the best dielectric properties with epsilon(r) = 27, Q(u) x f = 62,000 GHz, and tau(f) = (+)1.1ppm/degrees C. The effect of Ca substitution on the structure, microstructure and microwave dielectric properties of Li(2)A(1-x)Ca(x)Ti(3)O(8) (A = Mg, Zn and x = 0-0.2) has also been investigated. The materials reported in this paper are excellent in terms of dielectric properties and cost of production compared to commercially available high Q dielectric resonators. (C) 2010 Elsevier Ltd. All rights reserved.