Patent ID: 8314026

Claim:
A method of forming a conductive via comprising: forming a conductive contact structure having a surface of a conductive material; forming an undercutting layer over the conductive contact structure, the undercutting layer being of a different material than the surface of the conductive material; forming a dielectric layer over the undercutting layer and over the conductive contact structure, the undercutting layer located between the dielectric layer and the conductive contact structure; forming an opening in the dielectric layer over the conductive contact structure; removing material of the undercutting layer through the opening in the dielectric layer, wherein the surface of the conductive contact structure is exposed through the opening in the dielectric layer, wherein an opening formed by the removing of the material of the undercutting layer is wider than the opening in the dielectric layer such that the dielectric layer has an overhang portion adjacent the opening in the dielectric layer above the conductive contact structure; and filling the opening formed by the removing of the undercutting material and at least partially filling the opening in the dielectric layer with a conductive fill material, wherein the filling results in the conductive fill material being located between the overhang portion of the dielectric layer and the conductive contact structure, wherein: the filling the opening is performed such that the conductive fill material has an internal tensile stress to provide an upward pressure on the overhang portion, and the at least partially filling the opening includes filling the opening with the conductive fill material above a top surface of the dielectric layer and forming conductive fill material in an area over the to surface of the dielectric layer adjacent to the opening of the dielectric layer, wherein the conductive fill material has an internal tensile stress to provide a downward pressure on the top surface of the dielectric layer at the area adjacent to the opening of the dielectric layer.