| 摘要 |
PROBLEM TO BE SOLVED: To provide a wiring circuit board capable of sufficiently achieving high density mounting on an external conductive layer by electrically conducting between each of conductors without forming through holes, even in a multilayer wiring circuit board having four-layers of conductive layers. SOLUTION: In the four-layered wiring circuit board 14, two second conductor layers 3 are provided on both sides of a thermosetting adhesive layers 8, and two first conductor layers 2 are provided outside each of the layers 3 with an insulating layer 1 sandwiched. In this circuit board 4, the layer 3 of each double-sided substrate 4 is electrically connected to the layer 2 thereof by a blind hole plating layer 6 closed on the layer 2, and the respective layers 2 are electrically connected by a conducting layer 13 formed in the layer 8. In this way, the respective conductor layers can be electrically conducted without forming through holes, and connection pads are formed on arbitrary positions on a second surface of each of the layers 2 and electrical components can be mounted with high density. COPYRIGHT: (C)2005,JPO&NCIPI |
