Patent ID: 6812577
Filing Date: 2004-11-02
Classification: H01L

Abstract:
A semiconductor contact structure comprising:a semiconductor substrate; an interlayer dielectric layer disposed on said semiconductor substrate, said interlayer dielectric having a contact hole extending therethrough and exposing a region of conductive material on the semiconductor substrate, and said conductive material having an upper surface, and a recess therein contiguous to said contact hole, said recess being located below the upper surface of the conductive material and being wider than said contact hole as taken laterally in a direction extending along the upper surface of said substrate such that said recess undercuts sidewalls that define said contact hole; a spacer lining the sidewalls that define said contact hole, said spacer having a lower portion that extends beneath the level of the upper surface of said conductive material; and a contact plug having a lower portion that rests directly on said conductive material and fills said recess, and an upper portion that fills said contact hole, whereby the lower portion of the contact plug is wider than the upper portion of thereof so that the contact plug is stably supported in the structure.