| Abstract
| - Resonance Raman spectroscopy/microscopy was used to study individualized single-walled carbon nanotubes(SWNTs) both in aqueous suspensions as well as after spin-coating onto Si/SiO2 surfaces. Four differentSWNT materials containing nanotubes with diameters ranging from 0.7 to 1.6 nm were used. Comparisonwith Raman data obtained for suspensions shows that the surface does not dramatically affect the electronicproperties of the deposited tubes. Raman features observed for deposited SWNTs are similar to what wasmeasured for nanotubes directly fabricated on surfaces using chemical vapor deposition (CVD) methods. Inparticular, individual semiconducting tubes could be distinguished from metallic tubes by their different G-modeline shapes. It could also be shown that the high-power, short-time sonication used to generate individualizedSWNT suspensions does not induce defects in great quantities. However, (additional) defects can be generatedby laser irradiation of deposited SWNTs in air, thus giving rise to an increase of the D-mode intensity foreven quite low power densities (∼104 W/cm2).
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