@article{MalyarGorinSanteretal.2017, author = {Malyar, Ivan V. and Gorin, Dmitry A. and Santer, Svetlana and Stetsyura, Svetlana V.}, title = {Photo-assisted adsorption of gold nanoparticles onto a silicon substrate}, series = {Applied physics letters}, volume = {110}, journal = {Applied physics letters}, publisher = {American Institute of Physics}, address = {Melville}, issn = {0003-6951}, doi = {10.1063/1.4979082}, pages = {4}, year = {2017}, abstract = {We report on a photo-assisted adsorption of gold nanoparticles on a silicon substrate studied using atomic-force microscopy and secondary ion mass-spectrometry. Depending on a silicon conductivity type (n-Si or p-Si), the amount of photo-assisted adsorbed gold nanoparticles either increases (n-Si) or decreases (p-Si) on irradiation. In addition, the impacts of a cationic polyelectrolyte monolayer and adsorption time were also revealed. The polyelectrolyte layer enhances the adsorption of the gold nanoparticles but decreases the influence of light. The results of the photo-assisted adsorption on two types of silicon wafer were explained by electron processes at the substrate/solution interface. This work was supported by the German-Russian Interdisciplinary Science Center (G-RISC) funded by the German Federal Foreign Office via the German Academic Exchange Service (DAAD), Project No. P-2014b-1, and Russian foundation for basic research, Project No. 16-08-00524_a.}, language = {en} } @article{MalyarGorinSanteretal.2013, author = {Malyar, Ivan V. and Gorin, Dmitry A. and Santer, Svetlana and Stetsyura, Svetlana V.}, title = {Photocontrolled Adsorption of Polyelectrolyte Molecules on a Silicon Substrate}, series = {Langmuir}, volume = {29}, journal = {Langmuir}, number = {32}, publisher = {American Chemical Society}, address = {Washington}, issn = {0743-7463}, doi = {10.1021/1a403838n}, pages = {16058 -- 16065}, year = {2013}, abstract = {We report on a change in the properties of monomolecular films of polyelectrolyte molecules, induced by illuminating the silicon substrate on which they adsorb. It was found that under illumination the thickness of the adsorbed layer decreases by at least 27\% and at the same time the roughness is significantly reduced in comparison to a layer adsorbed without irradiation. Furthermore, the homogeneity of the film topography and the surface potential is shown to be improved by illumination. The effect is explained by a change in surface charge density under irradiation of n- and p-type silicon wafers. The altered charge density in turn induces conformational changes of the adsorbing polyelectrolyte molecules. Their photocontrolled adsorption opens new possibilities for selective manipulation of adsorbed films. This possibility is of potential importance for many applications such as the production of well-defined coatings in biosensors or microelectronics.}, language = {en} } @article{MalyarTitovLomadzeetal.2017, author = {Malyar, Ivan V. and Titov, Evgenii and Lomadze, Nino and Saalfrank, Peter and Santer, Svetlana}, title = {Photoswitching of azobenzene-containing self-assembled monolayers as a tool for control over silicon surface electronic properties}, series = {The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr}, volume = {146}, journal = {The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr}, publisher = {American Institute of Physics}, address = {Melville}, issn = {0021-9606}, doi = {10.1063/1.4978225}, pages = {8}, year = {2017}, 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). Itwas 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 thework 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. Published by AIP Publishing.}, language = {en} } @article{MalyarSanterStetsyura2013, author = {Malyar, Ivan V. and Santer, Svetlana and Stetsyura, Svetlana V.}, title = {The effect of illumination on the parameters of the polymer layer deposited from solution onto a semiconductor substrate}, series = {Technical physics letters : letters to the Russian journal of applied physics}, volume = {39}, journal = {Technical physics letters : letters to the Russian journal of applied physics}, number = {7}, publisher = {Pleiades Publ.}, address = {New York}, issn = {1063-7850}, doi = {10.1134/S1063785013070183}, pages = {656 -- 659}, year = {2013}, abstract = {The effect of illumination on the thickness and roughness of monolayers of polycationic molecules of polyethyleneimine deposited from solution onto a silicon substrate was discovered and investigated. The super-bandgap illumination of the substrate during polyethyleneimine adsorption causes a decrease in both the roughness and integral thickness of the organic layer on n- and p-Si substrates.}, language = {en} }