Commentary: Carbon-based Electrical Interconnect and Thermal Interface Materials

Summary form only given: As integrated circuit (IC) technology continues the trend towards sub-50 nanometer feature sizes, it is imperative to retain performance of back-end features such as on-chip interconnects while gaining the cost benefit of scaling. Some major barriers to achieving continuous downward scaling include high resistance and questionable reliability of nanoscale copper lines, and power dissipation in densely packed integrated circuits. This work presents fundamental electrical and thermal characterization of carbon nanofibers (CNF) as a possible solution for next-generation back-end integrated circuit processing. Results of temperature-dependent electrical resistance measurements for CNF arrays demonstrate distinct metallic behavior of these novel nanoscale devices. The current capacity of CNF interconnect test structures is examined and the results are compared with an electrothermal transport model. The use of CNF/copper composite material as a thermal interface for IC packaging is explored and fundamental thermal resistance measurement results show promise of such a composite material for thermal management applications.