Method to eliminate post-CMP copper flake defect

摘要

A method of copper metallization wherein copper flaking and metal bridging problems are eliminated by an annealing process is described. A first metal line is provided on an insulating layer overlying a semiconductor substrate. A dielectric stop layer is deposited overlying the first metal line. A dielectric layer is deposited overlying the dielectric stop layer. An opening is etched through the dielectric layer and the dielectric stop layer to the first metal line. A barrier metal layer is deposited over the surface of the dielectric layer and within the opening. A copper layer is deposited over the surface of the barrier metal layer. The copper layer and barrier metal layer not within the opening are polished away wherein after a time period, copper flakes form on the surface of the copper and dielectric layers. The copper layer and the dielectric layer are alloyed whereby the copper layer is stabilized and the copper flakes are removed to complete copper damascene metallization in the fabrication of an integrated circuit.