Diamond nanofabrication and characterization for biosensing application

Surface potential of the H-terminated and locally oxidized diamond surfaces is investigated by Kelvin probe force microscope. Potential of H-terminated diamond surface is observed to be similar to0.1 V higher than that of oxidized diamond surface. Surface potential difference is attributed to the surface charge induced by the electronegativity differences of the terminated atoms. The difference of DNA physisorption on the H- and O-terminated diamond surfaces due to the surface charging effect is also observed. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.