| 摘要 |
With a multi-layer printed circuit bare board has 2n circuit layers, where n is a natural number exceeding a unity, electrical connections are established between the (2i-1)-th layer and the 2i-th layer, where i=1, 2 . . . , n, by holes which are created through insulation material layers in between and filled with copper plating. Electrical connections are also accomplished between the 4i-th layer and the (4i-3)-th layer by holes created through insulation material layers in between and filled with copper plating. Higher dimensional accuracy and fewer process steps are achieved. |
