Investigating semiconductor layered systems of photonics

The structure of a heterostructures-based semiconductor laser is experimentally investigated by complex means involving systems of scanning electron microscopy, scanning probe microscopy, and Raman spectroscopy. The possibilities of high-resolution microscopy for diagnostics of layered microelectronic systems are demonstrated.     

Laser-Induced Nanocluster Thin-Film Systems with Controlled Topology and Composition: The Possibility of Creating Superconducting Structures Based on New Physical Principles

Crystallography Reports - The physical properties of solid structures depending on the boundary conditions in topologically ordered nanocluster systems are discussed. These systems are synthesized...     

Laser-induced synthesis of metal–carbon materials for implementing surface-enhanced Raman scattering

Metal–carbon materials exhibiting surface-enhanced Raman scattering have been synthesized by laser irradiation of colloidal systems consisting of carbon and noble metal nanoparticles. The dependence of the Raman scattering intensity on the material composition and laser irradiation conditions has been investigated. The possibility of recording the Raman spectrum of organic dye rhodamine 6G, deposited in amount of 10^–6 M on the substrate obtained from a colloidal solution is demonstrated.     

Optical properties of multilayer bimetallic films obtained by laser deposition of colloidal particles

The optical properties of multilayer bimetallic films composed of silver and gold nanoparticles have been investigated. The dependence of the transmission spectra of the films on their morphology is demonstrated. A finite-difference time-domain (FDTD) simulation has confirmed that there is a dependence of the transmission spectra on the average distance between particles and the number of deposited layers.     

Effect of the procedure for preparing porous membranes based on interpolyelectrolyte complexes on their structure,surface morphology,and surface electrical properties

Ultrafiltration membranes based on interpolyelectrolyte complexes of sulfonate-containing aromatic copolyamide, acrylonitrile–N,N-dimethyl-N,N-diallylammonium chloride copolymer, and poly-N,N-dimethyl-N,N-diallylammonium chloride were prepared. Their structure and surface electrical properties were studied. The correlation between the procedure for performing the interpolymer reaction, the degree of conversion, the composition of the resulting complex, and the membrane characteristics was revealed. The electrokinetic potential of the membrane specimens varies in the interval from–35.2 to +3.1 mV. The interpolymer compound composition, surface electrical properties of the membranes, and their activity in sorption of base and acid dyes correlate with each other. Therefore, it is appropriate to use these dyes as test systems for determining the nature and concentration of free ionic groups. The effect of the membrane preparation procedure on the charge distribution pattern on the membrane separation surface is considered.     

Measurements of electrophysical properties of metal microcontacts using fractal geometry methods for the analysis of atomic-force-microscopy data

A new approach to analyzing the conductivity of metal microcontacts of the fractal type is proposed. It is shown that the resistance of such a microcontact depends strongly on its morphology (total characteristic including the size, shape, and spatial organization, which are determined by atomic force microscopy). A method for calculating the resistance of a microcontact by measuring its height map is proposed.     

Pulse laser deposition of cluster nanostructures from colloidal single-component systems

We study the formation and deposition of clusters of nanoparticles from colloidal systems onto a support surface as a result of local pulse laser impact. The processes of abnormal diffusion influencing the formation of relief due to changes in the diffusion coefficient near surface irregularities are analyzed. Numerical simulation is performed for the mechanism of deposition of particles from the colloidal system as a result of local laser impact.     

Morphology of Pb<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Eu<Subscript>x</Subscript>Se epitaxial film surfaces after plasma treatment

The morphology of surfaces of Pb _1−x Eu _x Se epitaxial films on CaF ₂ /Si(111) substrates in the initial state and after treatment by high-density inductive Ar plasma in different regimes is investigated by the methods of atomic force microscopy. It is demonstrated that threading dislocations serve as cores for the formation of large bulges during sputtering of a semiconductor material. The influence of treatment regimes on the geometrical parameters of large bulges and characteristics of the surrounding nanorelief is revealed. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 90–93, November, 2007.