A structure and method of forming an improved metal cap for interconnect structures is described. The method includes forming an interconnect feature in an upper portion of a first insulating layer; deposing a dielectric capping layer over the interconnect feature and the first insulating layer; depositing a second insulating layer over the dielectric capping layer; etching a portion of the second insulating layer to form a via opening, wherein the via opening exposes a portion of the interconnect feature; bombarding the portion of the interconnect feature for defining a gauging feature in a portion of the interconnect feature; etching the via gauging feature for forming an undercut area adjacent to the interconnect feature and the dielectric capping layer; depositing a noble metal layer, the noble metal layer filling the undercut area of the via gauging feature to form a metal cap; and depositing a metal layer over the metal cap.