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Two different procedures of carbon nanotube film fabrication are discussed. The size, structural, and optical characteristics as well as electrophysical properties of initial nanotubes and the prepared buckypaper are studied. A nature of the observed temperature activated charge transport is discussed. Surprisingly, these data shows a fairly good agreement with the energy gap, originating from SWCNT curvature effects and intertube coupling. The parameters of electromagnetic radiation–buckypaper interaction are derived for the range of 37.5–78.33 GHz. Strong attenuation of the radiation up to 41 dB in this range is observed. Such results render this material promising for protection against electromagnetic radiation in sensitive devices and systems.

Self-consistent calculations of acoustic and polar optical phonon scattering rates in GaAs quantum wire transistor structures were carried out with account of collisional broadening. The influence of the gate bias on the scattering rates was examined, too. It was shown that in order to treat the scattering rates rigorously it is important to search for electron energy levels by means of the self-consistent solution of Schrodinger and Poisson equations and to take into account the collisional broadening. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The paper presents a mathematical-physical model of the formation of nitride phases in the course of implantation of big doses of nitrogen ions into copper and its alloys. Distributions of nitrogen atoms implanted into copper and brass obtained by means of the RBS method and calculated on the basis of the proposed model were compared and on that basis the value of the coefficient of radiation enhanced diffusion of nitrogen atoms in copper and brass was estimated.

Cathodoluminescence is employed to study the spatial distribution of radiation-induced defects and impurities in diamond and cubic boron nitride implanted with high-energy N, C, B, Ni, Co, Cu, and Xe ions. The results are compared with theoretical calculations made by moment method and Boltzmann equation. Experimental ion ranges correlate well with the corresponding theoretical values. With high-energy ion implantation, the spatial distribution of defect formation is mainly determined by the distribution of elastic energy deposition. Defect-stimulated diffusion of nitrogen, nickel, and xenon impurities is observed deep into the diamond crystal. [Russian Text Ignored].

The structure changes in (111)-Si layers as a function of ion implantation parameters, pulsed nanosecond annealing and following thermal treatment conditions are investigated using transmission electron microscopy. The models of liquid phase epitaxy, secondary defect formation during pulsed annealing and dislocation generation during tetrahedron stacking fault annealing are proposed. Depending on the impurity supersaturation level and oxidation intensity the formation of two or three perfect dislocations may take place under a single tetrahedron stacking fault annealing. [Russian Text Ignored].

The theory of charged particle energy loss by collisions as a function of impact parameter in a crystal is developed on the basis of the quantum dielectric formalism. Simple and convenient formulae taking into account the energy zone structure of crystals are obtained for nonrelativistic and relativistic particles. The relation between energy loss and local electron density is studied. For the first time it is shown strictly that the hyperchanneled particle energy loss in the axial channels is less than that in corresponding plane channels. Comparison with main experiments is presented. [Russian Text Ignored]

Kinetics of secondary structure defect formation in B+ ion-implanted Si crystals are investigated in isochronal and isothermal annealing experiments. The implantation dose is below the critical dose which forms a continuous amorphized layer. On the basis of quantitative results obtained an analysis of the behaviour of various defects is performed and the main factors and mechanisms which determine the evolution of such structures are established. [Russian Text Ignored]

Structure defects and the electrically active impurity distribution within (001)-oriented silicon layers after implantation of 100 keV 11B+ ions to a dose of 6.25 × 1014 ions/cm2 and subsequent annealing in inert (dry N2) and oxidizing (dry O2, steam) ambients are studied. It is found that annealing in oxidizing ambients as compared to that in N2 leads to the following results: i) a substantial increase in the density and size of the imperfect Frank dislocation loops; ii) a formation of dislocation configurations close to the misfit dislocations; iii) an enhancement of the boron diffusion; iv) a decrease in the electrically active boron near the silicon-oxide interface. The results obtained are interpreted in terms of the lattice oversaturation with silicon self-interstitials generated during the process of ion implantation and thermal oxidation as well as of the misfit stress influence. [Russian Text Ignored].

Thin films of transition metals (Ti, Cr, Ni, Nb, Mo, Ta) are bombarded with nitrogen and argon ions of energy 60 keV with dose range of 5 × 1015 to 5 × 1017 ions/cm2. The formation of chemical compounds causes both, the phase transformation and changes in the electrical properties of the films. The electrophysical and structural properties show a strong dependence on the conditions of film preparation. [Russian Text Ignored]

The theory of bremsstrahlung from relativistic particles as function of impact parameter is developed on the basis of the virtual photon method using the Moliere atomic potential. The contribution to the particle energy loss by collisions is calculated by means of the quantum dielectric formalism. The channeled-to-random energy loss ratio is calculated for both, light and heavy particles. For the hyperchanneled, ultrarelativistic positrons it is a value of the order of 10−2. For heavy particles the ratio is of the order of 0.5 to 0.2. On the contrary for channeled electrons there is an enhancement of the average energy loss as compared with the random case. The contributions of transition bremsstrahlung and Kumakhov radiation are discussed, too. Die Theorie der Bremsstrahlung relativistischer Teilchen wird entwickelt als Funktion des Stos-Parameters auf der Basis der Methode virtueller Photonen unter Anwendung von atomaren Moliere-Potentialen. Mit Hilfe des quanten-dielektrischen Formalismus wird der Beitrag von Stosen zum Energieverlust der Teilchen berechnet. Das Verhaltnis der Energieverluste fur kanalisierte und nichtkanalisierte Teilchen wird fur leichte und schwere Teilchen angegeben. Fur hyperkanalisierte ultrarelativistische Positronen ist das Verhaltnis von der Grosenordnung 10−2. Das entsprechende Verhaltnis fur schwere Teilchen ist von der Grosenordnung 0,5 bis 0,2. Im Gegensatz dazu erhoht sich fur kanalisierte Elektronen der Energieverlust im Vergleich zu nicht-kanalisierten. Beitrage von Ubergangsbremsstrahlung und Kumakhov-Strahlung werden diskutiert.

A complete interpretation is performed of the electron diffraction patterns of (001)- and (111)-oriented silicon single crystals bombarded by stoichiometric doses of carbon ions with 40 keV energy. The ion beam current density amounted ≈ 300 μA/cm2 with ion fluence of 6 × 1017 ions per cm2. It is found that highly intensive ion bombardment promotes the formation of a layer of silicon carbide of cubic modification (β-SiC) with first- and second-order twins deep in the sample. The electron diffraction analysis of the planar and back sides of bombarded silicon plates exhibit the availability of β-SiC inclusions on their surfaces. [Russian Text Ignored].

The elastic scattering cross-sections are calculated both in the framework of Lindhard wide-angle extrapolation method and on the basis of an exact solution of the classical equation of motion of a particle in a central-force potential. Using a direct method for the numerical solution of integro-differential equations governing the ion implantation spatial distribution parameters, the projected ranges, projected and lateral stragglings, and skewnesses are calculated in a wide interval of reduced energies. It is shown that for incident energies e < 0.1 all these parameters are affected by the choice of both the interatomic potential and elastic scattering cross-section approximation. [Russian Text Ignored].

An analytical version is derived of the modified Firsov theory for the calculation of inelastic energy losses of ions traversing through crystalline and amorphous targets. Shell effects are included. The model describes correctly the dependence of the inelastic energy loss on the atomic number of the target atoms and incident ions and yields a fair agreement with experimental data. [Russian Text Ignored].