Fabrication and material characterization of copper and copper–CNT micropillars

Abstract

In this work, copper micropillars and copper–carbon nanotube (CNT) composite micropillars were fabricated by incorporating an electrodeposition technique with a xurography process. In order to disperse carbon nanotubes in copper–CNT micropillars, various amounts of CNTs were added to the electroplating bath. Surface morphology and phase characterization of copper micropillars and copper–CNT composite micropillars were analyzed by optical microscopy and x-ray diffraction. In addition, the corrosion resistance (Rp) of a bare copper substrate, copper micropillars, and optimum copper–CNT micropillars were studied by electrochemical impedance spectroscopy (EIS) technique in a 3.5 wt.% sodium chloride. Experimental results yielded a corrosion resistance of 200 Ω cm2 for the bare copper substrate, 400 Ω cm2 for copper micropillars, and 2550 Ω cm2 for copper–CNT micropillars, indicating a significantly higher corrosion resistance for copper–CNT micropillars due to a lower chemical reactivity and refinement of crystal structure of copper in micropillars.