Design of low dielectric glass+ceramics for multilayer ceramic substrate

Compositional design and properties of a low dielectric constant glass+ceramics, containing borosilicate glass, high silica glass and alumina, for multilayer ceramic substrates are described. The new low dielectric system can be densified at below 1000/spl deg/C in air, allowing high electrical conductivity metallization including Au and Ag-Pd. Compositions with tailor-made properties are designed according to a working model based upon mixing rule, and validated with experimental results. Compositions with a thermal expansion coefficient compatible with Si and GaAs, and a dielectric constant in the range of 4-4.5 and 5-6, respectively, are developed.>