| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for forming a viahole of a wiring board wherein a viahole having high reliability can be formed by a small number of manufacturing processes. SOLUTION: In this method, a viahole 8 is formed on a wiring board 1 which has a metal layer 6 on the surface of a resin layer 7 by using a carbon dioxide gas laser L. In a first pulse, the metal layer 6 is irradiated with a carbon dioxide gas laser L1 of high energy. From a second pulse, the resin layer 7 is irradiated with carbon dioxide gas lasers L2, L3... of low energy, and a viahole 8 is bored.</p> |
