| 摘要 |
<p>PURPOSE:To prevent a gap from being produced in the wall of a through hole due to the difference of shrinkage rate between a ceramic material and a conductor material for filling the through hole. CONSTITUTION:A conductor 5 is formed on the wall of a through hole made through green sheets 1 provided, as the outermost layers, on the surface and rear of a ceramic board. The laminate having hollow through holes 4 is pressed and fired to obtain a ceramic board having such structure as the through holes are recessed thus preventing a gap from being produced in the wall of through hole.</p> |
