摘要 |
In a method of manufacturing a printed wiring board, a via reaches from a surface copper layer to an inner-layer copper layer of a multilayer board, and copper layers and insulating layers are alternately layered. The wiring board is machined by a laser, and a process of machining the via includes forming a laser absorbing layer on a surface of a copper layer disposed on the surface of the multilayer board. The laser is irradiated, and an electrolytic etching and removal of the laser absorbing layer is carried out in this order.
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