| 摘要 |
PURPOSE:To prevent positions of respective circuit layers from being shifted relatively to each other, by interposing a metal between the respective circuit layers and using holes formed on the periphery of one circuit layer so as to weld the metal with a metal foil of the other circuit layer and also by using holes formed on the other circuit layer so as to weld the metal with the metal foil of the one circuit layer so that the respective circuit layers are welded to each other. CONSTITUTION:Prepreg materials 3 and a metal A are interposed between both-sided printed circuit boards 1 and 2, and they are mounted on a positioning jig 10. Holes 5 of the both-sided printed circuit board 1 are used to spot-weld the metal A with a copper foil C on the circuit board 2 located on the opposite side of the holes 5 by means of a spot welding machine S. Further, holes 6 of the circuit board 2 are used to spot-weld the metal A with a copper foil B on the circuit board 1 similarly. Two printed circuit boards 1 and 2 welded and positioned in this way are joined and fixed to each other, and next they are dismounted from the positioning jig 10. The prepreg materials 3 and the copper foils 7, 8 are piled together and they are heated and pressed to obtain a multilayer printed circuit board 9. Hence, molding performance and interlayer positioning precision can be prevented from being deteriorated during multilayer molding. |
