SEM image of the tip structure. The distance between the tips is on the order of .
CVD/ethanol growth of CNT bridges. (a) Growth of two well aligned SWCNT. (b) A thicker bundle implying MWCNT. The CVD process differed mainly by the ethanol/Ar pressure which was in (a) and in (b). The growth temperature was the same, . All bridges were later analyzed by Raman spectroscopy.
Effect of high current on a CNT bridge. (a) SEM image of a CNT bridge, grown with ethanol in . The current-voltage measurement followed (b), assessing . (c) SEM of the same bridge albeit burnt after applying a high current. The sample was (1,0.5) with Co and Ti layers thickness of 20 and , respectively. [(d) and (e)] Grown at with CO flow rates of ; the tip structure enabled us to monitor the alignment of the bridge after the measurement (e).
Overlayers of thick formed by the CVD process at . We used ethanol in as a precursor. Two different areas are shown in the upper panels: in (b) a growth of MWCNT is shown, while in (ac) cobalt carbide layer begun to detach from the sample.
Temperature dependence of plasma enhanced CVD (PECVD) on CNT synthesis with ethanol: top panels were synthesized at and . (a) SEM image demonstrating well-aligned SWCNT embedded in opal matrix, whereas -carbon is clearly detected on (b). (c) Raman spectra for either sample exhibiting similar peaks, which are associated with SWCNT, with the exception of a disordered graphitic line at in (d). Raman spectra were taken with laser at and spot size of .
Plasma grown SWCNT with at . A pressure of and power was used for the top left panel (a), while and for the top right panel (b). The SEM images portray very short and aligned SWCNT. The deviation from a spherical shape of the silica on the right panel is due to charging effects. [(c) and (d)] The corresponding Raman spectra indicate a high frequency peak at and RBM mode at . Note that the sample presented at the right panel was coated by carbon for SEM imaging, which might contribute to the peak. laser was used with power and spot area. The two curves in (c) were taken at two different sample locations.
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