Suspended carbon nanotube thin film structures with high degree of alignment for NEMS switch applications

We describe microfluidic channel assisted carbon nanotube (CNT) alignment followed by microfabrication and characterization of a suspended CNT thin film. The alignment of CNT is enhanced by heating the CNT dispersion, which is characterized with Raman spectroscopy yielding a high G- to D-band intensity ratio of 22 along the microfluidic flow direction. The sidewall of CNT film pattern, left in a lift-off process, is eliminated by oxygen plasma etching. The resistivity of aligned CNT film is found as 1.45 × 10^-3 Ωcm. The aligned CNT film is released by etching a sacrificial layer of amorphous silicon and characterized mechanically demonstrating a nominal high Young´s modulus of 635 GPa and a yield strength of 2.4 GPa through a fixed-end beam deflection test. The lithography compatible fabrication process and the highly conductive film with an excellent mechanical property enable the aligned CNT film to be a potent candidate for nanoelectromechanical device applications.