title: Photoswitching of azobenzene-containing self-assembled monolayers as a tool for control over silicon surface electronic properties.
abstract: We report on photoinduced remote control of work function and surface potential of a silicon surface modified with a photosensitive self-assembled monolayer consisting of chemisorbed azobenzene molecules (4-nitroazobenzene). It was found that the attachment of the organic monolayer increases the work function by hundreds of meV due to the increase in the electron affinity of silicon substrates. The change in the work function on UV light illumination is more pronounced for the azobenzene jacketed silicon substrate (ca. 250 meV) in comparison to 50 meV for the unmodified surface. Moreover, the photoisomerization of azobenzene results in complex kinetics of the work function change: immediate decrease due to light-driven processes in the silicon surface followed by slower recovery to the initial state due to azobenzene isomerization. This behavior could be of interest for electronic devices where the reaction on irradiation should be more pronounced at small time scales but the overall surface potential should stay constant over time independent of the irradiation conditions.
authors.affiliation: Department of Nano- and Biomedical Technologies, Saratov State University, Astrakhanskaya 83, 410012 Saratov, Russia.
authors.forename: Ivan V
authors.initials: IV
authors.lastname: Malyar
authors.affiliation: Experimental Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany.
authors.forename: Evgenii
authors.identifier: 0000000217321826
authors.initials: E
authors.lastname: Titov
authors.affiliation: Experimental Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany.
authors.forename: Nino
authors.initials: N
authors.lastname: Lomadze
authors.affiliation: Theoretical Chemistry, Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Saalfrank
authors.affiliation: Experimental Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Santer