Low temperature reaction-sintering and microwave dielectric properties of ZnO–Nb₂O₅–2TiO₂ ceramics

Abstract

Low-temperature fired ZnO–Nb₂O₅–2TiO₂ ceramics co-doped with CuO–V₂O₅ were fabricated by a reaction-sintering process. CuO–V₂O₅ addition effectively lowered the sintering temperature of ZnO–Nb₂O₅–2TiO₂ ceramics to 950°C due to the liquid phase sintering. The phase compositions and microwave dielectric properties of ZnO–Nb₂O₅–2TiO₂ ceramics depended on the CuO–V₂O₅ content and sintering temperatures. Typically, 1.5 wt% CuO–V₂O₅ co-doped ceramics sintered at 950°C for 5 h exhibited optimum microwave dielectric properties of ε _r  = 45.9, Q × f = 12,200 GHz, τ _f  = −1.8 ppm/°C. In addition, such sample was compatible with Ag electrode, suitable for the low-temperature co-fired ceramics (LTCC) applications.