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Publications (2)5.04 Total impact

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    ABSTRACT: Nanoprobe chemistry offers a promising approach for the construction of nanostructures consisting of organic molecules by employing the tip of a scanning probe microscope. In a previous report, we demonstrated that a nitroso-terminated surface on an organosilane self-assembled monolayer could be converted into an amino-terminated surface by applying such a nanoprobe electrochemical technique. This paper reports on surface-potential reversibility originating from a reversible chemical reaction between amino and nitroso groups. In addition, we demonstrate surface-potential memory based on this chemical reversibility. Amino-terminated SAMs were prepared from p-aminophenyl-trimethoxysilane through chemical vapor deposition. Surface potentials were acquired by Kelvin force microscopy. When scanning probe lithography was conducted with a gold tip at positive-bias voltages, the surface potential of the scanned area shifted dramatically in the negative direction. Scanning with negative-bias voltages led to positive shift in the surface potential of the scanned area. The surface potential could be recovered even after multiple scannings with positive and negative applied bias voltages. On the basis of this discovery, we also succeeded in demonstrating surface-potential memory via our nanoprobe electrochemical technique.
    The Journal of Physical Chemistry B 07/2005; 109(23):11602-5. · 3.61 Impact Factor
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    ABSTRACT: Alkoxy-type organic monolayers on hydrogen-terminated silicon were prepared from 1-undecanol (UN), 1-nonanol (NO), 1-heptanol (HP), and 4-phenylphenenol (PP). These monolayers were characterized based on x-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). XPS spectra showed that the lowest amount of SiO_x oxide on the sample of the UN monolayer. On the other hand, a SiO_x peak was clearly observed for the HP, NO, and PP monolayers. The generation of SiO_x in the PP monolayer may have been due to steric hindrance of the aromatic rings. The–CH_2–region in the FT-IR spectra showed that shorter alkyl chains promoted the formation of gauche conformers in the monolayer. This increase of gauche conformers was determined to have caused the generation of SiO_x in the alkyl monolayers. Journal of Vacuum Science & Technology A 22(4), 2004, p.1425-1427
    Journal of Vacuum Science & Technology A Vacuum Surfaces and Films 01/2004; · 1.43 Impact Factor