| 摘要 |
PURPOSE: To ensure a reduced dielectric constant and a reduced coefft. of thermal expansion for a ceramic substrate fired at a low temp. CONSTITUTION: A ceramic material consisting of 50-64wt.% glass powder and 36-50wt.% Al2 O3 -mullite mixture is prepd. The glass powder has a compsn. consisting of, by weight, 10-55% CaO, 45-70% SiO2 , 0-30% Al2 O3 , 0-10% impurities and 5-20% B2 O3 basing on the total amt. of the components except B2 O3 . The mixture contains Al2 O3 contg. 0-10% impurities and >=5wt.% mullite. The ceramic material is fired at 800-1,000 deg.C to produce the objective ceramic substrate. Since the amt. of Al2 O3 blended is reduced and >=5wt.% mullite having a low dielectric constant and a low coefft. of thermal expansion is blended in place of Al2 O3 , a reduced dielectric constant and a reduced coefft. of thermal expansion are ensured for the substrate and the warpage of the substrate is suppressed when the substrate and a conductor are simultaneously fired. |
