| 摘要 |
PROBLEM TO BE SOLVED: To obtain a method for manufacturing printed wiring boards by which no migration is caused. SOLUTION: With regard to a so-called piercing method for manufacturing multilayer boards by which an almost conical conductor bump 2 is placed by a press in a prepreg of a substrate of insulating material and then is hardened for obtaining an electrical conduction in the direction of thickness of the substrate, wiring patterns are provided on one side of a substrate 3 of non-hardened insulating material, an electrical conduction is obtained in the direction of thickness of the substrate with conductor bumps in the substrate, then a plurality of such substrate units are layered and the prepregs of the substrates are hardened by heat at a time. |
