Low leakage metal-containing cap process using oxidation

An interconnect structure which includes a metal-containing cap located atop each conductive feature that is present within a dielectric material is provided in which a surface region of the metal-containing cap is oxidized prior to the subsequent deposition of any other dielectric material thereon. Moreover, metal particles that are located on the surface of the dielectric material between the conductive features are also oxidized at the same time as the surface region of the metal-containing cap. This provides a structure having a reduced leakage current. In accordance with the present invention, the oxidation step is performed after electroless plating of the metal-containing cap and prior to the deposition of a dielectric capping layer or an overlying interlayer or intralevel dielectric material.