| 摘要 |
PURPOSE:To enhance reliability in the connection with an upper conductor layer by forming a via fill through electroplating thereby preventing separation at the interlayer connecting part. CONSTITUTION:A signal line conductor layer 2a is formed on a ceramic board 1 and an inorganic insulating paste is printed onto the ceramic board 1 and the signal line conductor layer 2a. The paste is then dried to form an insulator which is subsequently exposed and developed to form a through hole. The insulator is then fired in a furnace at about 900 deg.C for about 1 hour to form a sintered insulator 5a while simultaneously obtaining a through hole 6. Finally, a via fill 3a is formed on the through hole 6 by electroplating. |
