Inhibition of silver diffusion in LTCC by MgTiO₃ addition

In this work, the effect of MgTiO₃ on silver diffusion in alumina/borosilicate low temperature co-fired ceramics was investigated. The added MgTiO₃ reacts with the glass to produce a new crystalline phase, which together with MgTiO₃, acts as a barrier to block the diffusion of silver. The diffusion coefficient of the sample sintered at 900 °C for 30 min was reduced from 6.07 × 10⁻¹³ cm²/s to 3.50 × 10⁻¹³ cm²/s, and the diffusion activation energy was increased from 89.4 kJ/mol to 117.2 kJ/mol. In addition, MgTiO₃ promoted the compaction of sintering. The dielectric properties of the samples sintered at 900 °C for 30 min with 25% MgTiO₃ added were determined to be ε_r = 7.8 and tanδ = 0.0005 (1 MHz), which are similar to the properties obtained for a sample with only alumina added (ε_r = 6.9, tanδ = 0.0005 at 1 MHz).