Ceramics-Silikáty 52, (3) 139 - 147 (2008)

The effects of CuO, TiO₂ and B₂O₃ additives on the dielectric and mechanical properties of a commercial, lead-free aluminoborosilicate glass and 40 wt. % of Al₂O₃ mixture system were investigated using a full-factorial design of experiments (DOE) technique for low temperature co-fired ceramic (LTCC) application. Sintered density, dielectric constant, and flexural strength were analyzed statistically as output responses for nine sample groups, according to the DOE table, after sintering at 900°C for 40 minutes in air. The optimum composition for this system was found to be the addition of 5 wt. % of CuO, TiO₂, and B₂O₃, which exhibited the dielectric constant of 8.3, relative density of 99%, and flexural strength of 258 MPa. These values were a marked improvement on those of the glass system. Due to the negligible second phase formation and interaction among the input factors associated with this experiment, Lichtenecker's mixing model was confirmed to represent accurately the dielectric constant behavior.