Self-assembly of a two-dimensional molecular layer in a nonhomogeneous electric field: Kinetic Monte Carlo simulations.

Behavior of mobile adsorbed species can be affected by the presence of a strong non-homogeneous electric field. Such a field exists in the proximity of a biased tip of the scanning tunneling microscope. Depending on the electronic properties of the adsorbate and the polarity of the electric field, self-assembly of ordered structures on the surface can be facilitated or prevented.

Local electronic structure of doping defects on Tl/Si(111)1x1.

The Tl/Si(111)1 × 1 surface is a representative of a 2D layer with Rashba-type spin-split electronic bands. To utilize the spin polarization, doping of the system should be understood on atomic level. We present a study of two types of atomic defects predicted to dope the considered electronic system - Si-induced vacancies and defects associated with the presence of extra Tl atoms.

Adsorption of ethylene on Sn and In terminated Si(001) surface studied by photoelectron spectroscopy and scanning tunneling microscopy.

Interaction of ethylene (C2H4) with Si(001)-Sn-2 × 2 and Si(001)-In-2 × 2 at room temperature has been studied using core level (C 1s) X-ray photoelectron spectroscopy with synchrotron radiation and scanning tunneling microscopy. Sn and In form similar dimer chains on Si(001)2 × 1, but exhibit different interaction with ethylene. While ethylene adsorbs on top of Sn dimers of the Si(001)-Sn-2 × 2 surface, the Si(001)-In-2 × 2 surface turned out to be inert.

Desorption-induced structural changes of metal/Si(111) surfaces: kinetic Monte Carlo simulations.

We used a configuration-based kinetic Monte Carlo model to explain important features related to formation of the (√3×√3)R30° mosaic of metal and semiconductor atoms on the Si(111) surface. Using first-order desorption processes, we simulate the surprising zero-order desorption spectra, reported in some cases of metal desorption from the Si(111) surface. We show that the mechanism responsible for the zerolike order of desorption is the enhanced desorption from disordered areas.

Chemical identification of single atoms in heterogeneous III-IV chains on Si(100) surface by means of nc-AFM and DFT calculations.

Chemical identification of individual atoms in mixed In-Sn chains grown on a Si(100)-(2 × 1) surface was investigated by means of room temperature dynamic noncontact AFM measurements and DFT calculations. We demonstrate that the chemical nature of each atom in the chain can be identified by means of measurements of the short-range forces acting between an AFM tip and the atom. On the basis of this method, we revealed incorporation of silicon atoms from the substrate into the metal chains.

Modeling growth of one-dimensional islands: influence of reactive defects.

Influence of reactive defects on size distribution of one-dimensional islands is studied by means of kinetic Monte Carlo simulations in combination with an analytical approach. Two different models are examined: a model with anisotropically diffusing atoms irreversibly aggregating to islands, and a reversible model close to thermal equilibrium which allows atom detachment from islands during the growth. The models can be used to simulate island growth of group III metals deposited on the Si(100)2 x 1 surface at room temperature: Al, Ga (irreversible model), and In (equilibrium model).

Direct observation of long-range assisted formation of Ag clusters on Si(111)7 x 7.

Formation of Ag clusters on reconstructed surface Si(111)7 x 7 was for the first time observed in real time during deposition by means of scanning tunneling microscopy. The sequences of images taken at room temperature show mechanisms controlling the growth and behavior of individual Ag adatoms. Obtained data reveal new details of attractive interaction between adsorbates occupying adjacent half-unit cells of the 7 x 7 reconstruction.