Studies on Structural, Microwave Dielectric Properties, and Low-Temperature Sintering of 1.52Li sub(2)O-0.36Nb sub(2)O sub(5)-1.34TiO sub(2) Ceramic

The structure, microwave dielectric properties and low-temperature sintering of a new Li2O-Nb2O5-TiO2 system ceramic with the Li2O ; Nb2O5 : TiO2 mole ratio of 1.52: 0.36: 1.34 have been investigated in this study. The 1.52 Li2O-0.36 Nb2O5-1.34TiO2 (LNT) ceramic is composed of two phases, the "M-Phase" and Li2TiO3 solid solution (Li2TiO3ss) phase. This new microwave dielectric ceramic has low intrinsic sintering temperature ( ~ 1100 oC ) and good microwave dielectric properties of middle permittivity ( epsilon r ~38.6), high Qxf value up to 7712 GHz, and near zero Tf value (~ 4.64 ppm/oC). In addition, the sintering temperature of the LNT ceramics could be lowered down effectively from 1100 oC to 900 oC by adding 1 wt.% B2O3. Good microwave dielectric properties of epsilon r = 42.5, Q*f =6819 GHz and Tf = 2.7 ppm/oC could be obtained at 900 oC, which indicate the ceramics would be promising candidates for low-temperature co-fired ceramics (LTCC) applications.