| 摘要 |
PURPOSE:To obtain a ceramic substrate having low dielectric constant, showing a coefficient of thermal expansion close to that of Si by burning a green sheet consisting of Al diffused glass powder prepared by heat-treating a mixture of alumina and borosilicate glass at high temperature, borosilicate glass and quartz glass. CONSTITUTION:A mixture of 20-75% Al2O3 and 80-25% borosilicate glass is heat-treated at <=1,000 such as 1,300 deg.C, then ground to give A1 (ion) diffused glass powder. Then, a green sheet of a mixture of 10-75% of the glass powder, namely in which Al ion sufficiently diffused and 5-70% borosilicate glass is formed. By burning the green sheet, glass is efficiently prevented from crystallizing by the addition of a small amount of Al2O3 to give a ceramic substrate having a coefficient of thermal expansion close to that of Si. |
