PLANAR SUBSTRATE AND METAL INTERFACE FOR RF, MICROWAVE AND MM WAVE SYSTEMS

摘要

The present invention includes a method of making a device that eliminates a vertical transition from a substrate to a metal structure comprising: providing a lapped and polished substrate with at least one metal trench or via in the substrate having a transition between a surface of the substrate and a surface of the metal; coating or depositing on the substrate the same metal as the metal in the trench or via, wherein a thickness of the coated or deposited metal is at least twice the thickness of the transition; chemically-mechanically polishing at least 50% of the thickness of the coated or deposited metal; and using an etching process to etch the deposited material on the surface of to eliminate the vertical transition from the surface of the substrate to the metal trench or via.