Glass-ceramic composite material and multilayered circuit substrate

Abstract

A glass-ceramic composite material for use in forming a multilayered circuit substrate is provided which has a low dielectric constant, but exhibits a relatively high thermal expansion coefficient. Specifically, the glass-ceramic composite material comprises a glass power and a ceramic powder. The glass powder contains: about 30 to 60 mol % of SiO2, about 20 to 40 mol % of BaO, 0 to about 40 mol % of MgO, 0 to about 40 mol % of ZnO, 0 to about 20 mol % of B2O3, with the total content of MgO and ZnO being about 10 to 40 mol %. The ceramic powder contains an alumina powder. The content of the glass powder is set to be at least about 50 wt %. A sintered compact formed by sintering the above glass powder and the above ceramic powder contains a BaO.Al2O3.2SiO2 (BaAl2Si2O8) crystal, and its Q value becomes about 400 or more when a measured frequency is 10 GHz.

Dependencies are inferred from the claim text.