Patent ID: 6727174
Filing Date: 2004-04-27
Classification: H01L

Abstract:
A method for fabricating a dual-diameter electrical conductor comprising the steps of:providing a substrate having a first conductive region formed of a first conductive material, depositing a layer of a first dielectric material on said substrate, etching a first opening in said first dielectric material layer by reactive ion etching to expose said first conductive region in the substrate, depositing a second conductive material into said first opening in said first dielectric material layer forming a body portion of the conductor, removing a surface layer of said second conductive material to at least partially expose an upper sidewall surface in said first opening, forming sidewall spacers of a second dielectric material on said upper sidewall surface of said first opening thereby defining a second opening through which said body portion of the conductor is exposed, and depositing a third conductive material into said second opening and forming a neck portion of the conductor that is in contact with the body portion of said conductor, said neck portion having a diameter at a top surface of the neck portion smaller than a diameter of said body portion.