Patent ID: 7143509

Claim:
A process of fabricating a circuit board, comprising the steps of: providing a first laminated structure having at least three first circuit layers and at least two first dielectric layers, wherein the first circuit layers and the first dielectric layers are alternately laminated wit one of the first dielectric layers sandwiched between two neighboring ones of the first circuit layers, and none of the first dielectric layers has a conductive via that only passes through a single one of the first dielectric layers; forming at least a plated through hole that passes through the first laminated structure; laminating a middle dielectric layer and a second laminated structure over the first laminated structure, wherein the middle dielectric layer is disposed between the first laminated structure and the second laminated structure; and forming at least a second plated trough hole tat passes through the first laminated structure, the middle dielectric layer and the second laminated structure.