MULTILAYERED LAMINATED SUBSTRATE HAVING HIGH DENSITY INTERCONNECTIONS AND ITS MANUFACTURE

摘要

PROBLEM TO BE SOLVED: To manufacture a multilayered substrate having a high signal density at low costs with a smaller number of steps and without reducing the productivity, by forming an electrical connection between a pad of a first circuit layer and a pad of a second circuit layer using a conductive substance. SOLUTION: A first surface of a bonding sheet is laminated to a second surface of a first circuit layer 10 by thermocompression bonding, and holes are formed which end at a pad on the first surface of the layer 10 while passing through a release layer, the bonding sheet and the layer 10. Then, a hole in the release layer adhered to the bonding sheet is filled with a conductive substance that is in contact with the pad of the layer 10. The release layer is removed form the bonding sheet. The bonding sheet is then laminated to a first surface of a second circuit layer by thermal compression to thereby allow the hole to face the pad of the second circuit layer. The conductive substance forms an electrical connection between the pad of the layer 10 and the pad of the second circuit layer.