The natural beryl crystals have been irradiated by 40 keV iron ions with fluence of 1.5xl017 ion/cm2 on an ion beam accelerator. For an annealing of radiation defects and a redistribution of implanted iron ions, the thermal treatment of irradiated beryls has been performed in oxygen during 30 min. at 600 °C. Crystal-chemical peculiarities of irradiated beryls were then investigated by optical absorption and Mössbauer spectroscopy. Iron irradiation and following a thermal annealing of non-colored beryl have led to alteration of color of crystals into orangeyellow. It was established that the iron ions implanted in beryl's structure are localized in octahedral and tetrahedral sites, where they substitute aluminum and beryllium ions by isomorphic way.

Preliminary conductance measurements of Si implanted, α-Quartz which had been annealed in ar to 1000• C have been made using a bridge method. the quartz was implanted to a dose expected to yield Si precipitates inside the quartz upon annealing. the measured conductivity, based on a geometry deduced from TRIM calculations and several trans-conductance measurements, is ~ 2 х 10-4(Ω m)-1. This is consistent with large islands of Si in series with an insulating matrix.

Implantation of high-energy cobalt ions into plates of synthetic rutile has been studied, and absorption, luminescence, and luminescence excitation spectra have been recorded and interpreted. Long-wave luminescence (820 nm) of Ti IV 3+ ions in rutile has been revealed; its intensity increased after the cobalt implantation. Analysis of luminescence and luminescence excitation spectra has allowed us to specify the scheme of electron energy levels of rutile and to establish the energy levels of impurity Ti3+ ions occupying vacant octahedrons with the C 2h symmetry in structure of the mineral.

Single crystalline plates of corundum (Al2O3) were implanted by 40 keV cobalt ions with high fluences in the range of 0.5-1.5x10 ion/cm to synthesize new nanostructured magnetic materials. Magnetic properties of Co-implanted plates were studied by coil magnetometry, differential thermo-magnetic analysis and ferromagnetic resonance (FMR) technique in X-band (9.8 GHz). With the increase of fluence the implanted corundum plates reveal sequentially superparamagnetic, weak ferromagnetic and, eventually, strong ferromagnetic properties at room temperature. The thermo-magnetic analysis shows that the formation of cobalt nanoparticles with the ferromagnetic ordering temperature (TC~1000K) occurs in the implanted region of corundum. Strong out-of-plane angular dependences of the hysteresis loops and FMR spectra observed in the ferromagnetic samples are typical of a thin granular cobalt film embedded in a diamagnetic host such as Al2O3.

Проведена имплантация высокоэнергетичных ионов кобальта в пластины синтетического рутила. Обнаружена необычно длинноволновая люминесценция (820 нм) ионов в рутиле, интенсивность которой возрастает после имплантации кобальтом. Анализ спектров люминесценции и спектров ее возбуждения позволил уточнить схему электронных уровней рутила и определить в ней уровни энергии примесных ионов Ti3+, заселяющих вакантные октаэдры с симметрией C2h в структуре минерала.

Dynamics of recrystallization of implanted silicon surface has been investigated using an in situ diffraction method. The method is based on registering the diffraction signal from a special periodic structure formed by ion implantation. The change of the intensity of the diffraction maximum may enable one to define the moment when recrystallization of the amorphous layer ends, the moment when the local melting of the surface starts and the duration of the stage when the liquid phase exists. Investigation of the dynamics of recrystallization and anisotropic local melting of implanted silicon under irradiation by pulses of incoherent light with different duration and power densities has been carried out. Our method enables one to carry out rapid thermal annealing with a feedback on the ending of recrystallization. This provides a better control on the formation of shallow p–n junctions.

The (100)- and (001)-monocrystalline plates of rutile (TiO2) were implanted by 40keV Co+ ions with fluences in wide range of 0.15–1.5×1017ion/cm2 to study the development of ferromagnetism in the diamagnetic TiO2. With increase of fluence the implanted rutile plates reveal sequentially paramagnetic, superparamagnetic, weak ferromagnetic and, eventually, strong anisotropic ferromagnetic response at room temperature. The thermo-magnetic analysis shows that the ferromagnetic samples exhibit two magnetic transitions with temperatures of the ferromagnetic ordering TC1∼700K and TC2∼850K, correspondingly. Heating of the samples in air strongly suppresses the ferromagnetic phases if the temperature of heating exceeds the corresponding transition temperature. Subsequent high-vacuum annealing restores only the low-temperature ferromagnetic phase. The origin of the two magnetic phases and anisotropy of the ferromagnetism in the Co-implanted rutile are discussed in the model of two cobalt-rich layers with different concentration and valence states of the implanted cobalt.

Electronic properties and magnetoresistance of polyimide (PI) films implanted by 40 keV Co+ ions with high fluences at various ion current densities are studied. Insulator-to-metal transition (IMT) is found for the highest implantation fluence (1.25 x 10(17) cm(-2)) at ion current densities of 8 and 12 mu A/cm(2). The IMT is caused by the radiation-induced alteration of the implanted PI and agglomeration of the Co nanoparticles (NPs) providing an efficient percolation way for the charge carriers. Impedance spectroscopy shows the increase in capacitance with fluence for the samples on the dielectric side of the IMT, which is caused by formation of the conductive metal NPs and carbonised clusters separated by insulating polymer media. The percolation of the conductive phase for the samples on the metallic side of the IMT results in an inductive character of the impedance. The magnotoresistive effect is found to be positive for the samples on the dielectric side of the IMT and negative for the samples on the metallic side. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The optical and electrical properties of diamond-like carbon films implanted with copper ions with energy 40 keV and implantation doses ranging from 3 × 1014 to 3 × 1017 ion/cm2 are studied. The effect of postimplantation thermal annealing on the properties is examined. It is established that the copper atoms implanted with doses below 6 × 1015 ion/cm2 have no effect on the properties of the carbon films. Post-implantation thermal annealing at temperatures below 500°C does not induce any activation of the copper impurities. However, the formation of copper nanoparticles brings about specific changes in the optical and electrical properties of the carbon films. It is found that for the composite films, the effective optical gap determined from the Tauc plot is a function of the filling factor of the metal phase and can take negative values. It is shown that the optical absorption of the synthesized copper-carbon films in the visible and near-infrared spectral regions can be adequately described using a two-layer model. The formation of copper nanoparticles in the carbon matrix modifies the temperature dependence of the conductivity; however, the hopping mechanism of charge transport remains unchanged.

The effect of intense atomic hydrogen flux on the defect density in the surface layer of single-crystal silicon is studied. It is shown that the formation of local molten regions by pulsed-light heating of Si samples and further analysis of the local melting pattern can be an efficient tool for determining the number of defects introduced by the processing in atomic hydrogen. It was found that the processing conditions in atomic hydrogen with an exposure dose lower than 2.7 × 1017 cm−2 do not change the number of defects in Si; in contrast, conditions with an exposure dose above 3.6 × 1018 cm−2 significantly increase the defect density. The increase in the number of defects can be caused by the interaction of atomic hydrogen with the Si surface.

The present review concentrates on the fabrication of metal nanoparticles in sapphire matrix by ion implantation and their modification by laser annealing. This approach is promising for the development of optical composite materials in the optoelectronics production technology. Composite layers were fabricated in sapphire by implantation of 40-keV Cu+ ions at a dose of 1.0,10(17) ion/cm(2) and an ion beam current density varying from 2.5 to 10 mu A/cm(2). The composites were examined by different methods: Rutherford backscattering (RBS), atomic force microscopy (AFM) and optical spectroscopy. It is shown that ion implantation is suited for creation of copper nanoparticles in the near-surface sapphire layer. However, the nanoparticle size distribution in this layer is nonuniform. An interaction of high power excimer laser pulsed with fabricated composite layer aimed to modify the sizes and the size distribution of copper particles. It is found that the laser annealing diminishes nanoparticles in the sapphire. Experimental data on laser modification may be explained by photofragmentation and/or melting of the nanoparticles in the sapphire matrix.

Different polymers (viscous-flow epoxies, viscoelastic silicone resins and solid state polyimides) were implanted with 40 keV Fe+ or Co+ ions to the doses of 0.1÷2.0×1017 ions/cm2. The influence of the dose and viscosity of polymer target on the process of nucleation and growth of metal nanoparticles in the implanted polymers as well as on the magnetic properties of ion-synthesized composites were investigated by electron microscopy and magnetic resonance. The implantation of the polymers with 40 keV ions causes a surface carbonization of polymer substrate and at the doses more than 0.25×1017 ions/cm2 results in the formation of metal (iron or cobalt) nanophase in thin subsurface layer. Mean sizes, crystalline structure, shape and space packing of the ion-synthesized nanoparticles strongly depend on the dose, kind of implanted ions and the polymer viscosity during implantation. The ion synthesis of the isolated cubic or spherical particles with the mean sizes in the range of 2÷200 nm, as well the formation of many-particles clusters, fractal-type agglomerates and single microscaled plates are observed in the implanted polymers under study. Ion-synthesized iron or cobalt nanoparticles reveal the magnetic resonance response, and at high doses their resonance signals demonstrate the typical features of ferromagnetic resonance in granular magnetic films. The values of magnetization and coercivity of the granular composite films were obtained from the analysis of FMR data. The non-linear dependencies of the composite magnetization on ion dose and on the viscosity of polymer target are presented and discussed in the frame of the magnetic percolation transition in the many-particles system.

Cobalt silicide layers were formed in Si and Si1-xGex/Si heterostructures by using ion beam synthesis (IBS) at specified regimes and conditions. Effect of the type of the initial target and its temperature during implantation on the phase composition and structure of synthesized layers were investigated. The nonmonotonic dependence of the sheet resistance of synthesized films on ion current density was detected. Thin CoSi2 films on Si0.6Ge0.4 structures with the sheet resistance of 17 Ohm/ were obtained using IBS with subsequent rapid thermal annealing.

The processes in the synthesis of iron silicide thin films (FeSi and FeSi2) on a single-crystal Si substrate implanted with different doses of Fe+ ions (D 10(15)-2 x 10(17) cm(-2)) and subjected to pulsed laser annealing (lambda=0. 69 mum, tau = 80ns, W = 0. 6-1.4 J cm(-2)) are investigated. Using x-ray diffraction, transmission electron microscopy and Rutherford backscattering spectrometry, the structure and phase composition of the synthesized films and the depth profile of Fe atoms in the Si are studied. It is shown that laser annealing (W = 0.6-1.1 J cm(-2)) of high-dose implanted Si (D > 10(17) cm(-2)) results in the formation of epitaxial iron monosilicide (FeSi) layers. Increasing the pulse energy up to 1.4 J cm-2 leads to a redistribution of Fe atoms in the Si and formation of a mixture of silicide phases (FeSi + FeSi2) with the cellular structure of a synthesized layer. In the case of low-dose implanted Si (D similar to 10(16) cm(-2)), the formation of cellular structures takes place at lower energy densities (W similar to 0. 8 J cm(-2)), with segregation of Fe atoms to the Si surface.

Investigation of the dynamics of recrystallization and anisotropic local melting of implanted silicon under irradiation by pulses of incoherent light with different duration and power densities has been carried out. Dynamics of recrystallization of implanted silicon surface has been investigated in situ using a diffraction method. The method is based on the registering of the diffraction signal from a special periodic structure with high time and spatial resolution. This periodic structure is formed using special regimes of implantation of phosphorus and silicon ions in monocrystalline silicon with different fluencies.

This paper presents a group of studies on the synthesis of diamondlike films of hydrogenated carbon by the decomposition of acetylene in an rf-discharge plasma (the PCVD method). The optical and strength-related properties of the films are investigated as a function of the synthesis regimes, and the deposition rates are determined. A number of tests of films on glass and germanium substrates have been carried out under extreme conditions in order to determine their stability against various kinds of external effects. It is established that, owing to their optical, strength-related, and chemical properties, the resulting carbon films can be used in IR engineering as multifunctional coatings of optical elements. The resulting film-deposition rates are evidence of high productivity of the PCVD method. (C) 2004 Optical Society of America.

Strengthening of flux-line pinning in high-Tc compounds by ferromagnetic particles created by implantation of iron ions has been observed. Measurements were carried out at single crystals of Bi2Sr2CaCu2O8 and thin films of YBa2Cu3O7 by means of field-modulated microwave absorption technique. In case of YBa2Cu3O7, experiments were performed on composite structure consisting of the superconducting film and non-conducting SiO2 film containing magnetic particles.

This paper discusses how bombardment by krypton ions with an energy of 20 keV affects the microrelief and light scattering of reflective aluminum layers. It is established that, for Grazing angles of incidence of the ions (about 85degrees), smoothing of the microrelief occurs, and the light scattering is reduced by at least a factor of 5. It is established that ion polishing occurs in a definite interval of irradiation doses. The ion polishing of ruled diffraction gratings (1200 lines/mm) reduces their light scattering by a factor of 3. (C) 2004 Optical Society Of America.