| 摘要 |
PROBLEM TO BE SOLVED: To provide a multilayer printed wiring board which allows simple formation of a via hole with a stable form and has a via excellent in electric characteristics.SOLUTION: A multilayer printed wiring board formation method comprises: a process of forming a via land protection pattern on a via land on a circuit wiring surface where a wiring layer including a via land pattern is provided; a process of performing a roughening treatment on the circuit wiring board including the via land protection pattern; a process of separating the via land protection pattern from the circuit wiring board; a process of forming an insulation layer on the circuit wiring board by lamination; and a process of applying laser beams on the insulation layer on the via land.SELECTED DRAWING: Figure 2 |
