Methods and apparatus for forming a semiconductor device are provided which may include any number of features. One feature is a method of forming an interconnect structure that results in the interconnect structure having a top surface and portions of the side walls of the interconnect structure covered in a dissimilar material. In some embodiments, the dissimilar material can be a conductive material or a nano-alloy. The interconnect structure can be formed by removing a portion of the interconnect structure, and covering the interconnect structure with the dissimilar material. The interconnect structure can comprise a damascene structure, such as a single or dual damascene structure, or alternatively, can comprise a silicon-through via (TSV) structure.