Growth and field emission properties of small diameter carbon nanotube films
نویسندگان
چکیده
Vertically aligned carbon nanotube films with diameters smaller than 5 nm, high densities up to 10/cm, and lengths of ~ 5–8 Am were deposited by microwave plasma-assisted chemical vapor deposition. Experiments show that, by continuous reduction in the thickness of the iron film (i.e., ~0.3–0.5 nm), small diameter carbon nanotubes can be achieved with diameters that ranged from 1–5 nm, and the films are comprised of both singleand double-wall nanotubes. The electron field emission properties of the films were investigated by variable distance field emission and temperature-dependent field electron emission microscopy (T-FEEM). The films showed an emission site density of ~10/cm and a threshold field of 2.8 V/Am similar to multiwalled nanotubes (1.9 V/Am). In addition, they also exhibited a temperature dependence of the emission site intensity. D 2004 Elsevier B.V. All rights reserved.
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