Sintering behaviors, microstructures and dielectric properties of CaO-B2O3-SiO2 glass ceramic for LTCC application with various network modifiers content

CaO-B2O3-SiO2 (CBS) glass ceramic with various glass network modifiers were synthesized to develop a kind of material sintered at low temperature for multi-layer ceramic substrates. The influence of double alkali metal oxides (Na2O and K2O) on sintering characteristics, microstructures and dielectric properties of CBS glass ceramic were investigated. XRD analysis showed that the major crystalline phase was beta-CaSiO3 and CaB2O4, and the strength of the peak increased with the addition of network modifiers. DSC curve revealed that the process of crystallization and softening were obviously affected. SEM photographs exhibited that the microstructures were composed of amorphous phases, pores and crystalline phases. FTIR showed that the additives changed the continuity of CBS glass structure. An appropriate amount of Na2O and K2O additives could significantly improve the sintering characteristics and dielectric properties. CBS samples with 1.5 wt% (Na2O + K2O) sintered at 850 degrees C for 15 min presented the best performances with the bulk density of 2.53 g/cm(3), epsilon(r) = 5.94 and tan delta = 1.22 x 10(-3) at 10 GHz.

Automated summary

The study focused on the impact of double alkali metal oxides on CaO-B2O3-SiO2 glass ceramic, and found that adding an appropriate amount of Na2O and K2O significantly improved the material's properties, such as sintering characteristics and dielectric properties.