A semiconductor device includes a recess defined in a dielectric layer, the recess having an upper sidewall portion extending to an upper corner of the recess and a lower sidewall portion below the upper sidewall portion. An interconnect structure is positioned in the recess. The interconnect structure includes a continuous liner layer having upper and lower layer portions positioned laterally adjacent to the upper and lower sidewall portions, respectively. The upper layer portion includes an alloy of a first transition metal and a second transition metal and the lower layer portion includes the second transition metal but not the first transition metal. The interconnect structure also includes a fill material substantially filling the recess, wherein the second transition metal has a higher wettability for the fill material than the alloy.