Process for forming passivated metal interconnection system with a planar surface

Claim 1

A process for forming an embedded interconnection metallurgy system on a substrate comprising: forming a first layer of an organic thermosetting polymerized resin material on the top surface of said substrate; forming a second overlying layer of a second organic polymerized resin material that is soluble in a solvent that does not appreciably affect the material of said first layer; forming a third thin layer resistant to reactive ion etching in O 2 on said second layer, depositing a resist layer over said third layer, exposing the resist to form an inverse pattern of the desired metallurgy pattern and developing the resist; removing the resultant exposed areas of said third layer; reactive ion etching the resultant exposed areas for a time sufficient to completely remove the exposed portions of said first and second layers; depositing over said third layer and exposed areas of said substrate a blanket conductive metal layer having a thickness approximately matching the thickness of said first layer; and exposing said substrate to a solvent that is selective to the material of said second layer for a time sufficient to remove said second layer and overlying portions of said conductive metal layer.