| Abstract
| - This paper describes a facile approach to the site-specific growth of single-walled carbon nanotubes (SWNTs)on silicon surfaces by chemical vapor deposition (CVD). The approach is based on the use of a surfactant asa resist to define patterns of silicon oxide nanodomains onto which nanoparticles of iron hydroxide (Fe(OH)3), 1−5 nm diameter, could be deposited. In base growth mode, the SWNTs can grow from the oxidenanodomains. By controlling the location of oxide nanodomains, site-specific growth could be obtained. Theiron hydroxide nanoparticles were prepared by hydrolysis of ferric chloride (FeCl3). Patterned hydroxylatedsilicon oxide nanodomains were created by scanning probe oxidation (SPO) of silicon substrates modifiedwith aminopropyltrimethoxysilane (APTMS, H2N(CH2)3Si(OCH3)3). Due to electrostatic interaction, Fe(OH)3nanoparticles can be selectively deposited on hydroxyl groups present on silicon oxide nanodomains. Toinhibit the assembly of the nanoparticles on a APTMS-coated silicon surface, sodium dodecyl sulfate (SDS)was introduced, which restricted deposition to the hydroxylated nanodomains. A model mechanism for theselective deposition mechanism has been proposed. It was possible to convert the patterned Fe(OH)3nanoparticles to iron oxide, which served as a catalyst for the site-specific growth of SWNTs. Ramanspectroscopy and AFM were used to characterize the nanotubes on the Si substrate. This will offer the possibilityfor future integration with conventional microelectronics as well as the development of novel devices.
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