Patent ID: 8192805

Claim:
A method of forming a doped layer, the method comprising: planarizing a top surface of a workpiece to form a substantially planar surface with a plurality of copper conductive paths and a plurality of dielectric regions; infusing a dopant material into and below the planarized top surface of the workpiece using a gas cluster ion beam (GCIB) to form a doped layer from the top surface to a desired depth of about 50-200 angstroms beneath the top surface in the plurality of copper conductive paths and the plurality of dielectric regions, wherein the dopant material comprises one or more dopant elements selected from the group consisting of B, C, Si, Ge, N, P, As, O, S, and Cl, and wherein said doped layer comprises between 0.1 atomic % and 10 atomic % of the dopant material; and forming a diffusion barrier layer over the doped layer as a barrier to diffusing copper atoms, wherein the doped layer minimize electromigration of copper in the conductive paths.