SUSPENDED CARBON NANOTUBE THIN FILM STRUCTURES WITH HIGH DEGREE OF ALIGNMENT FOR NEMS SWITCH APPLICATIONS

摘要

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.