Process for design and manufacture of fine line circuits on planarized thin film dielectrics and circuits manufactured thereby

Abstract

A circuit board having a structure including a permanent photoimageable dielectric material suitable for fabrication of vias both by laser ablation, plasma ablation, or mechanical drilling techniques and by photoimaging techniques. A process is also disclosed for the manufacture of a multi-level circuit on a substrate having a first-level circuitry pattern on at least one side. The process comprises applying a permanent photoimageable dielectric over the first-level circuitry pattern; exposing the permanent photoimageable dielectric to radiation; laminating a conductive metal layer to the dielectric; making holes in the conductive metal layer and dielectric by mechanical drilling or by laser or plasma ablation; and making a second-level circuitry pattern and filling the holes with a conductive material to electrically connect the first and second layers of circuitry. A further process is claimed for designing a multi-level circuit board product comprising making a prototype having the above structure in which the holes are manufactured by mechanical drilling or by laser or plasma ablation, evaluating the prototype, and then manufacturing a commercial circuit board having essentially the same structure and materials of construction as the prototype, but wherein the holes are manufactured by photoimaging techniques.

Dependencies are inferred from the claim text.