2011/01/11 by Shashank Shekhar, Shekhar, Shashank, Paul Stokes +3 · 2 citations
Engineering · Materials Science · Physics and Astronomy · #Carbon Nanotubes in Composites #Carbon fibers #Carbon nanotube #Composite material #Composite number #Dielectrophoresis #FOS: Physical sciences #Materials science #Mechanical and Optical Resonators #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Nanotechnology #Nanotechnology research and applications #Optoelectronics #cond-mat.mes-hall
paper · pdf · doi:10.48550/arxiv.1101.2237
published in arXiv (Cornell University) (Cornell University) · 12 Pages, 8 figures
arxiv created 2011/01/11 · openalex publication_date 2011/01/11 · arxiv updated 2011/01/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report ultra-high density assembly of aligned single walled carbon nanotubes (SWNTs) two dimensional arrays via ac dielectrophoresis using high quality surfactant free and stable SWNT solutions. After optimization of frequency and trapping time, we can reproducibly control the linear density of the SWNT between prefabricated electrodes from 0.5 SWNT/\mum to more than 30 SWNT /\mum by tuning the concentration of the nanotubes in the solution. Our maximum density of 30 SWNT/\mum is the highest for aligned arrays via any solution processing technique reported so far. Further increase of SWNT concentration results dense array with multiple layers. We discuss how the orientation and density of the nanotubes vary with concentrations and channel lengths. Electrical measurement data show that the densely packed aligned arrays have low sheet resistances. Selective removal of metallic SWNTs via controlled electrical breakdown produced field effect transistors (FET) with high current on-off ratio. Ultra-high density alignment reported here will have important implications in fabricating high quality devices for digital and analog electronics.