INFIQC   05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
“Electrodeposition of copper onto organic functionalized and hydrogen-terminated Si(111) surfaces”
Autor/es:
MA. BERNARDA QUIROGA ARGAÑARAZ; G. RIVEROS PATRONI; G. I. LACCONI
Lugar:
Erlangen, Alemania
Reunión:
Simposio; 5th Schwabe Symp 09; 2009
Resumen:
Electrodeposition of copper onto organic functionalized and hydrogen-terminated Si(111) surfaces Ma. Bernarda Quiroga Argañaraz1, Gonzalo Riveros Patroni2, Gabriela I. Lacconi1* 1 INFIQC, Depto. Fisicoquímica, Facultad Ciencias Químicas, Universidad Nacional de Córdoba, Argentina. 2Depto. Química y Bioquímica, Facultad Ciencias, Universidad de Valparaíso, Chile. *E-mail: glacconi@mail.fcq.unc.edu.ar The study of the organic modification of hydrogen-terminated silicon surfaces has been promoted by the development and design of molecular scale devices. The preparation of hybrid molecular-semiconductor devices or chemical biosensors requires a detailed understanding of the interface between silicon and organic layers. Silicon surfaces can be quite stable in air if they are covered with hydrogen, however, their resistance to the oxidation is increased by the organic film formation. Several authors have proposed different chemical, photochemical and electrochemical methods to the preparation of densely compact alkyl monoloyers covalently attached to the silicon surfaces [1-4]. The purpose of this work was the formation and characterization of hydrogenterminated Si(111) and organic functionalized surfaces with covalently attached alkyl chains monolayers. The study of organic monolayers formation when n-Si(111)-H surfaces react with 1-octadecene in a formal hydrosilylation reaction was performed. The precursor agent reacts efficiently with the hydrogen-terminated Si(111) when heated at temperatures over 140ºC or under exposition to UV radiation (λ = 254 nm). The electrochemical characterization of the organic functionalized silicon surfaces was performed by cyclic voltammetry and electrochemical impedance spectroscopy, principally related to the inhibition of the oxide formation. Direct correlations between the electrical properties of the film, hydrophobicity of the layer and passivation of the surface with the experimental conditions of the synthesis are established. On the other side, copper was electrodeposited onto the functionalized silicon surface by the application of potential pulses. The results show that the nuclei formation occurs at the monolayers defects. The kinetic of nucleation and growth of the copper crystals was established by the analysis of the current transients at different potential values. Structural characterization of the derivatized surfaces and the copper deposited crystallites was performed by ex-situ NC-AFM. 1- Linford, M.R.; Fenter, P.; Eisenberger, P.M.; Chidsey, C.E.D. J. Am. Chem. Soc. 1995, 117, 3145. 2- Sieval, A.B.; Vleeming, V.; Zuilhof, H.; Sudhölter, E.J.R. Langmuir 1999, 15, 8288. 3- Allongue, P.; de Villeneuve, C.H.; Cherouvrier, G.; Cortes, R.; Bernard, M.C.; J. Electroanal. Chem. 2003, 550-551, 161. 4- Balaur, E.; Djenizian, T.; Boukherroub, R.; Chazalviel, J.N.; Ozanam, F.; Schmuki, P.; Electrochem. Comm. 6 (2004) 153.