Sn-doped BaO–TiO₂–ZnO Microwave Ceramics

Sn-doped BaO–TiO₂–ZnO (BTZ) microwave ceramic materials were investigated as a function of SnO₂ content. Addition of a small amount of SnO₂ (0.01–0.06 wt%) lowered the sintering temperature of the system to 1160 °C and also greatly reduced the dielectric loss (tan δ), which is closely related to the insulation resistivity. The Sn-doped BTZ materials were found to have excellent dielectric properties at 1 GHz with dielectric constant Ε ≈tangent tan δ ≤ 1 × 10₋4, temperature coefficient of dielectric constant, α_Ε = 0 ± 30 ppm/°C, and volume resistivity ρ_v ≥ 10₁₃ ω cm.