Electronic and optoelectronic properties of devices with stripes of dense, aligned carbon nanotubes
C. Cates, W. Eades, S. Hu, J. Iyer, S. Sinton, T. Stachowiak, S. Winzer, C.L. Pint, R.H. Hauge, X. Zhou, A.A. Talin
Lockheed Martin, US
Keywords: aligned carbon nanotube SCWNT device electronic
Abstract:Many envisioned electronic and optoelectronic applications of carbon nanotubes (NTs) will require a high density of NTs. While much work has been done to address this need using NT mats, aligned SWCNTs are desirable to reduce the effects of NT-NT junctions, including in signal loss and in 1/f noise. Solution-based techniques for aligning NTs over large areas are promising, but have been so far limited to relatively short nanotubes, making device fabrication more difficult. In this paper, we present an approach that solves both of these issues, and allows the fabrication of electronic and optoelectronic devices with dense arrays of aligned nanotubes with channel lengths in the 10 micron range. Patterned catalyst lines were used to grow self-supporting, vertical stripes of carbon nanotubes that are over ten microns long. These stripes, when laid over onto the substrate, form dense ensembles of aligned nanotubes. Electronic and optoelectronic devices have been fabricated from such aligned NT stripes, where the NTs are long enough to span the entire distance between the electrodes. The degree of alignment of the nanotubes in the stripe materials has been characterized using polarized Raman spectroscopy. Electrical and optical characteristics of these devices will be presented.