Fabrication and Characterization of Nanoporous Metallic Interconnects Using Electrospun Nanofiber Template and Electrochemical Deposition

In this work, a nanocomposite interconnect consisting of ferromagnetic and non-ferromagnetic materials is theoretically and experimentally investigated. The relative magnetic permeability of ferromagnetic nanofibers becomes negative above the ferromagnetic resonance frequency and induces eddy current in an opposite direction of that of non-ferromagnetic conductor, resulting in eddy current cancellation. This ultimately suppresses the skin effect contributing to the reduction of radio frequency resistance. For nanofiber fabrication, an alternating electrospinning technique is utilized to improve the nanofiber growth rate and increase the thickness of the nanofiber stack. Aligned nanofibers are obtained by dynamically rotating mandrel combined with alternating electrospinning. Nanoporous conductors with the composition of non-ferromagnetic and ferromagnetic conductors are realized by electrochemical deposition of copper with the ferromagnetic nanofiber stack as a plating template.