Electrical characterization of single walled carbon nanotube networks obtained by dielectrophoresis
Dielectrophoresis is a process in which micro/nano particles align in an applied electric field. The effects of electric field and ultrasonication on the deposition and alignment of single-walled carbon nanotubes (SWCNTs) across a 10 μm electrode gap have been studied in this thesis. Increasing the ultrasonication time of a SWCNT solution changes the I-V characteristics of the deposited nanotubes from linear to nonlinear for all voltages(10 V, 15 V and 19 V) and frequencies (100 KHz-20 MHz) of the applied field. Even in the absence of an electric field, SWCNTs bridged the electrode gap up to a critical sonication time which depends on the concentration of nanotubes in the solution. The I-V characteristics were nonlinear for all ultrasonication times for the no-field results. It was found that a frequency of 1 MHz of the applied field yields the largest current independent of the magnitude of the voltage or the ultrasonication time of the sample. Electromigration (EM) was used as an alternate method to obtain an electrode gap. The results obtained from the gap formed by EM were similar to the results obtained from the commercially obtained electrodes.
Santosha L Ammu,
"Electrical characterization of single walled carbon nanotube networks obtained by dielectrophoresis"
Dissertations and Master's Theses (Campus Access).