Method for making integrated circuit including interconnects with enhanced electromigration resistance using doped seed layer and integrated circuits produced thereby

Abstract

A method for making an integrated circuit device includes forming at least one interconnect structure adjacent a substrate by forming at least one barrier layer, forming a doped copper seed layer on the at least one barrier layer, and forming a copper layer on the doped copper seed layer. The method may further include annealing the integrated circuit device after forming the copper layer to diffuse the dopant from the doped copper seed layer into grain boundaries of the copper layer. The doped copper seed layer may include at least one of calcium, cadmium, zinc, neodymium, tellurium, and ytterbium as a dopant to provide the enhanced electromigration resistance. Forming the copper layer may comprise plating the copper layer. In addition, forming the copper layer may comprise forming the copper layer to include at least one of calcium, cadmium, zinc, neodymium, tellurium, and ytterbium as a dopant. In some embodiments, the dopant in the seed layer may be sufficient so that no additional dopant is needed in the copper layer.