Bilateral Science and Technological Cooperation:

Serbia – France, 2007 – 2008

(Ministry of Science, Republic of Serbia – Bilateral Cooperation)

PROJECT TITLE: " Semiconductor functionalization processed by low-energy electron irradiation of condensed alcohols and amines "

PRINCIPAL INVESTIGATOR – Republic of France:

Dr. Roger Azria,

LCAM, Orsay, azria@lcam.u-psud.fr

PARTICIPANTS: Dr. Anne Lafosse, Matieu Bertin

PRINCIPAL INVESTIGATOR – Republic of Serbia:

Dr. Bratislav Marinković,

Institute of Physics (IPB), Pregrevica 118, P.O.Box 68, 11080 Belgrade, bratislav.marinkovic@ipb.ac.rs

PARTICIPANTS: Dr. Dragutin Šević, Aleksandar Milosavljević

Project description

The coupling of biomolecules with inorganic material to form hybride bioinorganic interfaces will be investigated because of their potential importance in several areas of technological interest, including biosensors, biomedical implants, and organic/biomolecular electronics. A method was developed in the Orsay Laboratory to functionalize semi-conductor substrate (hydrogenated diamond, hydrogenated silicon…). A condensed layer of organic molecules of interest (amine, amide, alcohol) is deposited onto the substrate at very low temperature and is irradiated using low-energy electrons (0.5-25 eV). This leads to the creation of reactive species, and to subsequent strong chemical modifications of the film and of the substrate surface itself (electron induced reactivity), by chemisorption of key chemical functions, like acidic and amino groups, onto the surface (functionalization). For the control and the orientation of the functionalization, electron interactions with the initially condensed molecules will be studied in both phases: gas (Institute of Physics, Belgrade – IoP) and condensed at low temperature (LCAM, Orsay).

Measurements in gas phase:

• Absolute elastic differential cross sections DCS; domain of scattering angles (30 – 130 deg.); domain of impact electron energies (40 – 300 eV)
• Electron energy loss spectra in the energy range up to ionization limit
• Positive ion angular distribution from binary collisions by electrons
• Energy analysis of positive ions emerging from dissociation processes upon electron impact

Measurements in condensed phase at 35 K:

• Electron induced dissociation processes leading to the formation of reactive molecular fragments (for instance to the formation of amino groups NH₂) in the energy range 0.7 – 25 eV studied by Electron Induced Desorption of negative ions.
• Chemisorption of organic functions at the substrate surface monitored with HREELS (High Resolution Electron Loss Spectroscopy).