Controlled Deposition and Electrical Characterization of Multi-Wall Carbon Nanotubes

A method of ac dielectrophoresis was applied to align and deposit metallic multi-wall carbon nanotubes between pre-fabricated metal (Au, Pd) electrodes with a micron scale separation. For improvement of nanotube contacts with electrodes, Ni and Pd electroless processes were developed, and significant reduction of 2 terminals resistances was demonstrated. Further, using electron and ion beam deposited Pt contacts in two different configurations (“Pt-on-CNT” and “CNT-on-Pt”), 4 terminals measurements have been performed to evaluate intrinsic nanotube resistances. The values between 90 and 130 kΩ/μm were obtained, while systematically lower values (30-70 kΩ/μm) were estimated using 2 terminals method. The 4 terminals method was applied to study the effect of ion irradiation on the electrical parameters of supported nanotubes.