Patent ID: 6143658
Filing Date: 2000-11-07
Classification: H01L

Abstract:
A method of fabricating a device with wires on at least two levels thereof comprising:forming a wire first level of wire in a substrate, wherein the wire is copper or a copper-containing metal;forming an insulating film over the first level of wire;forming at least one via in the insulating film, wherein the via communicates with at least one wire in the first level;forming a barrier metal layer over the surface of the substrate with the via formed therein;etching the substrate using an anisotropic reactive ion etch so that the barrier metal is selectively removed from at least the bottom of the via;subjecting the substrate to an oxygen or hydrogen plasma;immersing the substrate in an aqueous solution of hydrofluoric acid; andexposing the substrate to a reactant gas for a time sufficient to remove essentially all of the oxide on the exposed surface of the first level metal; andforming via plugs by depositing copper or a copper containing metal in the via.