Patent ID: 6290860
Filing Date: 2001-09-18
Classification: H05K

Abstract:
A process for manufacture of a circuit board on a substrate having a top side and a bottom side and a first-level circuitry pattern on at least one of said sides, the process comprising the steps of:a) applying a permanent photoimageable dielectric material over said first-level circuitry pattern;b) blanket-exposing said permanent photoimageable dielectric material to radiation;c) laminating a layer of conductive metal to said dielectric material;d) making holes in said layer of conductive metal to uncover portions of said dielectric material, and making holes in said dielectric material to uncover portions of said first-level circuitry pattern, said holes in said dielectric material being made by a method selected from the group consisting of mechanical drilling, laser ablation, and plasma ablation; ande) making a second-level circuitry pattern on said dielectric material, said making said second-level circuitry pattern comprising placing a conductive material in said holes in said layer of conductive metal and in said holes in said dielectric material to electrically connect said second-layer circuitry pattern and said first-layer circuitry pattern.