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The experience of hip arthroplasty in 22 children (23 joints) treated in the Department of Pediatric Bone Pathology and Adolescent Orthopedics of CITO is presented. The main group of operated were children with stage III coxarthrosis due to osteochondrodysplasia (10) and congenital dislocation of the hip (6). The duration of follow-up is from 1 to 23 years. A good result was obtained in 13 cases, satisfactory - in 7. Unsatisfactory results were associated with suppuration (1) and instability of the endoprosthesis (2). The authors see bilateral arthroplasty as a way to normalize the biomechanics of standing and walking in patients with osteochondrodysplasia.

Four cases of operative treatment for ochronosis arthropathy in patients with alcaptonuria are presented. In 3 patients hip joint and in 1 patient knee joint were affected. Prior to surgery all patients were treated conservatively. Two patients successfully underwent total hip replacement. Intertrochanteric femur osteotomy was performed in 1 case. In the fourth patient arthroplasty of knee joint with allograft from rib cartilage failed due to suppurative arthritis resulted in joint resection and arthrodesis.

From 1990 to 2000 238 revision hip joint replacements were performed at Joint Replacement Department of CITO. Both cement and cementless implants as well as in case of need allografts in the form of bone chips and spongeous bone were used. Technique peculiarities of revision operations for Sivash and Compomed implants replacement are described. The working time for Com- pomed implants was detected to be up to 5 у ears, for Gerchev implants up to 7 years and for Sivash implants 10 years and more. In revision replacement the following complications occurred: lethal outcome 2 cases, acute myocardial infarction in early postoperative period 1 case (recovery), deep suppuration 1 case (implant was removed), thromboembolia of small branches of a. pulmonalis 3 cases (recovery), paresis of fibular portion of n. ischiadicus 5 cases (complete function restoration), dysbacteriosis during antibacterial therapy 2 cases (recovery). Results of treatment were evaluated in 140 patients in the periods from 3 months to 10 years. In 139 cases complete or almost complete restoration of operated limb function was clinically noted. In 37 out of 139 patients signs of bone resorption around the cup and stem of implant were detected roentgeno- logically.

We report on the results of analysis of the structure and chemical composition of the surface of c-Si single crystal substrates implanted with Cu+ ions with energy of 40 keV and doses in a range of 3.1 × 1015–1.25 × 1017 ions/cm2 for a current density of 8 μA/cm2 in the ion beam. It has been established using scanning electron microscopy and probe microscopy combined with X-ray photoelectron and Auger spectroscopy that at the initial stage, the implantation with Cu+ ions to a dose of 6.25 × 1016 ions/cm2 induces the formation of Cu nanoparticles with an average size of 10 nm in the Si surface layer. Upon a further increase in the implantation dose, beginning with 1.25 × 1017 ions/cm2 and higher, the nucleation of the η phase of copper silicide (η-Cu3Si) is observed. This is due to heating of the surface layer of the Si substrate during its irradiation to a temperature facilitating the formation of the η-Cu3Si phase.

A novel technological approach based on ion implantation for obtaining nanostructured substrates for the visual characterization of ultrasmall biological objects and microorganisms has been described. By means of argon-ion implantation of silicate glasses through surface masks made of copper wire mesh, periodic microstructures in the form of gratings with mesh sizes of 50 × 50 μm were formed. The novel substrates were tested by scanning electron microscopy and energy-dispersive X-ray analysis, as well as atomic force microscopy, using bacteria of the genera Bacillus and Staphylococcus deposited onto their surface.

Reflection and transmission spectra in the range 200–1100 nm of thin (40 μm) polyamide films implanted with Co+ ions of energy 40 keV at ion-current density 4 μA/cm2 in the dose range 2.5·1016–1.5·1017 cm–2 are measured. The implantation leads to a significant (up to 80%) decrease of transmission through the implanted films and an increase of reflection from both the implanted and nonimplanted sides because of carbonization of the surface layer and formation of cobalt inclusions in it. Transmission of light incident on the implanted and nonimplanted sides was simulated and the dose dependence of the effective refractive index of the modified layer was determined in the framework of two- and three-layer models including one or two modified layers and the undamaged part of the film. The effective refractive index in the studied dose range was within 1.3–2.1.

We report on the results of first practical observations of sputtering of the Si surface during the implantation with Ag+ ions with an energy of 30 keV depending on irradiation dose D in the interval from 2.5 × 1016 to 1.5 × 1017 ion/cm2 for a fixed value of ion beam current density J = 8 μA/cm2, as well as for variation of J = 2, 5, 8, 15, and 20 μA/cm2 at constant D = 1.5 × 1017 ion/cm2. In the former case, the thickness of the porous Si (PSi) layer being sputtered increases monotonically to 50 nm at the maximum value of D; in this case, the effective sputtering ratio of the implanted Ag : PSi layer is 1.6. We have also established that the thickness of the sputtered layer increases with current density J.

The surface morphology of nanoporous Ge (PGe) layers formed by low-energy high-dose implantation with transition metal ions depending on their mass (52Cr+, 55Mn+, 56Fe+, 59Co+, 59Ni+ and 63Cu+) was studied by high-resolution scanning electron microscopy. Ion implantation of single-crystal c-Ge substrates was carried out using similar conditions with an energy of E = 40 keV and a dose of D = 5.0·1016 ion/cm2. Additionally, c-Ge was also implanted with heavier ions 108Ag+ and 122Sb+ at E = 30 keV for comparative experiments on the surface PGe morphology. It was observed that the morphology of the PGe layers changed with increasing mass of the irradiated ion from a labyrinth, hole type, three-dimensional network to spongy structure.

We present results of structural (XPS) and magnetic resonance (EPR) studies of single-crystal plates of strontium titanate (SrTiO3) heavily doped with chromium utilizing ion implantation technique. It was shown that the temperature of the oxide matrix during ion implantation (300 or 900 K) significantly affects the valence state of the implanted chromium impurity (Cr0 or Cr3+) and the depth profiles of its distribution in the SrTiO3 matrix. Using the EPR method, it was established that as a result of implantation of chromium impurity at an elevated substrate temperature during irradiation, the dominating color centers in the surface implanted oxide layer appear in the form of trivalent chromium ions in a cubic environment with a g-factor g = 1.976 and the value of the hyperfine coupling constant with the magnetic nucleus of 53Cr isotope, A = 16.2 × 10–4 cm–1. From a comparison of these data with parameters for the cubic Cr3+ impurity center in the SrTiO3 single crystal, it was concluded that this center is localized in the structural positions of titanium. Upon implantation of a chromium impurity in SrTiO3 at room temperature of the substrate, in addition to cubic Cr3+ centers, new signals were detected in the EPR spectra, apparently associated with the formation of oxygen vacancies in the implanted oxide. However, the number of these additional centers does not change significantly even after high-temperature heat treatment of samples in air at temperatures up to 900 K. It is noted that signals of this type also appear in the spectra of SrTiO3 samples obtained as a result of hot implantation and then subjected to high-temperature thermal annealing.

An approach for creating of a diffraction chalcogenide semiconductor glass grating on the surface of (GeSe5)80B20 layer by low-energy high-dose mask ion implantation is presented. During Ag+-ion implantation, Ag nanoparticles were synthesized in unprotected areas of irradiated glass. The formation of periodic surface microstructures during local ion sputtering of semiconductor glass was observed by scanning electron and atomic force microscopy. With probed a He-Ne laser the efficiency of optical diffraction grating was demonstrated.

Results are presented of a study of the morphology of germanium films nanostructured by ion implantation. Film samples were grown by magnetron sputtering in an ultrahigh-vacuum installation and then irradiated with 40 keV Ge+ ions at fluences in the range of (1.8–8) × 1016 ions/cm2. Scanning electron microscopy demonstrated that vacancy complexes with diameters of ~50–150 nm are gradually formed in the bulk of implanted germanium with increasing implantation fluence. After a certain implantation fluence is reached, the complexes emerge on the surface, thereby forming a developed surface profile of the irradiated films.

In the present work, a novel technological approach based on ion implantation for obtaining microstructured substrates for the statistical analysis and visual characterization of ultra-small biological objects and microorganisms is developed. By means of the argon-ion implantation of silicate glasses through surface masks made of wire mesh, periodic surface nanostructures in the form of gratings with mesh sizes of 500 × 500 nm are formed. The obtained novel substrates are tested using atomic force microscopy and scanning electron microscopy with energy dispersive analysis using bacteria of the genus Bacillus deposited onto their surface.

We have implanted ZnO thin film with 40 keV Fe+ ions to a high fluence of 1.25 × 1017 ions/cm2. Elemental and magnetic phase compositions were investigated by XRD, XPS, CEMS, and VSM methods. The Fe-implanted ZnO film reveals strong ferromagnetism at room temperature. The implanted iron ions are found in different valence states of Fe2+ and Fe3+. It was attributed to the formation of paramagnetic and ferromagnetic iron-based phases. The ferromagnetism is explained with the formation of a magnetic ordered solution of iron ions in ZnO matrix. Post-implantation annealing in a high vacuum results in the decrease of magnetism due to the formation of magnetite nanoparticles.

A new method of forming substrates (devices) with periodic micron surface grids for statistical analysis and visual characterization of ultra-small biological objects and microorganisms is suggested. For this aim an implantation by Ar+ of silicate glasses through surface masks as wire meshes is used to form surface periodic structures in the form of grating with cell sizes of 25 μm and a depth of 100 nm. Testing of novel types of devices was carried out applying scanning electron and atomic force microscopy, as well as EDX analysis using substrates with deposited bacteria as Bacillus subtilis.

Results are given for a spectral ellipsometry study of silicon surfaces implanted with oxygen ions in the dose range 7.5·1014–3.7·1016 ions/cm2 and helium ions in the range 6·1016–6·1017 ions/cm2 with energy 40 keV at constant ion current density 2 μA/cm2. The irradiated substrates were at room temperature. Curves are shown for the dependence of the thickness of the implanted layer in the irradiated plates and the dependence of the extent of amorphization of this layer on the ion implantation dose.

Structural and photoelectric properties of composite Ag:Si layers formed in the near-surface area of a single-crystal c-Si substrate by a high-dose implantation of Ag+ ions with subsequent pulsed laser annealing (PLA) have been studied. It has been established that, as a result of ion implantation, a maximal concentration of Ag impurity (NAg ~ 4 × 1022 at/cm3) is concentrated near the surface and drops to a level of ~1019 at/cm3 at a depth of ~60 nm. Meanwhile, Ag nanoparticles and silver oxide (Ag2O) inclusions are contained in a formed thin layer of amorphized Si (a-Si). Melting of a near-surface area and diffusion redistribution of the implanted impurity have been achieved in conditions of PLA, which increases Ag concentration near the surface and at a depth of 60 nm. Dark current–voltage characteristics of a junction between a Ag:Si layer and a p-Si substrate showed formation of a diode structure as a result of PLA. Photoconductivity measurements on formed samples demonstrate the presence of a photoresponse (photo-EMF) in the range of wavelengths of 500–1200 nm, which intensity increased for samples that are subjected to PLA when increasing energy density in the pulse. The obtained results demonstrate the potential use of composite Ag:Si layers and the method of their formation in the technology of photodetectors.

Low-energy (E = 30 keV) Ag+ ions have been implanted into single-crystalline Si wafers (c-Si) with an implantation dose varying from 1.25 × 1015 to 1.5 × 1017 ions cm–2 and an ion beam current density varying from 2 to 15 μA/cm2. The surface morphology of implanted wafers has been examined using scanning electron microscopy, transmission electron microscopy, and atomic force microscopy, and their structure has been studied by means of reflection high-energy electron diffraction and elemental microanalysis. It has been shown that for minimal irradiation doses used in experiments, the surface layer of c-Si experiences amorphization. It has been found that when the implantation dose is in excess of the threshold value (~3.1 × 1015 ions cm–2), Ag nanoparticles uniformly distributed over the Si surface arise in the irradiated Si layer. At a dose exceeding 1017 ions cm–2, a porous Si structure is observed. In this case, the Ag nanoparticle size distribution becomes bimodal with coarse particles localized at the walls of Si pores.

Ag+-ion implantation of single-crystal c-Si at low-energy (E = 30 keV) high-doses (D = 1.25⋅1015–1.5⋅1017 ion/cm2) and current density (J = 2, 8, 15 μA/cm2) was carried out. The changes of Si surface morphology after ion implantation were studied by scanning electron and atomic force microscopy. The near surface area of samples was also analyzed by diffraction of the backscattered electrons and energy-dispersive X-ray microanalysis. At the lowest implantation doses of c-Si amorphization of near-surface layer was observed. Ag nanoparticles were synthesized and uniformly distributed over the near Si surface when the threshold dose of 3.1⋅1015 ion/cm2 is exceeded. At a dose of more than 1017 ion/cm2, the formation of a surface porous Si structure was detected. Ag nanoparticle size distribution function becomes bimodal and the largest particles were localized along Si-pore walls.

The optical characteristics of Ag/ZnO composite nanostructures have long been of particular interest and, thus, the subject of broad experimental and theoretical studies. This work is focused on the synthesis and properties of Ag/ZnO nanocomposites and demonstrates the possibility of their application as active substrates for surface-enhanced Raman spectroscopy (SERS) in detection of pesticides. The samples were synthesized by pulsed laser deposition (PLD) of ZnO thin films, followed by Ag+-ion implantation in the ZnO matrix and by laser annealing of the heterostructures produced. The morphology and properties of the samples were studied with respect to the processing parameters. The optical absorption studies revealed the existence of tunable surface plasmon resonance of silver nanoparticles in the ZnO matrix. Theoretical calculations of the optical properties, as extinction, absorption and scattering efficiencies, were performed based on a generalized multi-particle Mie (GMM) approach. The simulated system assumed in this comparative study consists of a surface-embedded ensemble of silver nanoparticles in a ZnO surrounding media and in air. The simulated structures were reproduced from the corresponding SEM images after laser annealing at 355 nm and 532 nm.

Ag/ZnO composite nanostructures are produced by combined laser and ion implantation techniques. The ZnO layers are grown on SiO2 (001) and Al2O3 (r-cut) substrates by pulsed laser deposition (PLD) in vacuum and in oxygen ambient using a third-harmonic Nd:YAG laser. The ion implantation allows the introduction of Ag nanoparticles (NPs) in the surface of the ZnO matrix. These NPs are incorporated into the ZnO matrices to fabricate metal-semiconductor nanocomposites with the aim of manipulating their functionalities, exploiting the characteristics of both the matrix and the metal NPs. The composite samples are modified by laser annealing at 355 nm and 532 nm. The changes are investigated in the plasmon resonance absorption of the nanostructures before and after the annealing. The influence is explored of the different substrates used and the deposition conditions of ZnO growth on the properties of Ag/ZnO. The nanostructures obtained are efficient as SERS substrates for detection of ammonium nitrate under laser excitation at 633 nm. The SERS enhancement is attributed to the synergistic interactions between the plasmonic coupling among the surface embedded AgNPs and the enhanced charge transfer properties of the ZnO.

Recent experiments on fabrication of nanoporous Si and Ge layers with Ag nanoparticles by low-energy high-dose ion implantation are discussed. Ag+-ion implantation of c-Si and c-Ge single-crystals at low-energy (E = 30 keV) high-doses (D = 1.25 × 1015–1.5 × 1017 ion/cm2) and current density (J = 2–15 μA/cm2) was carried out for this purpose. The changes of Si and Ge surface morphology after ion implantation were studied by scanning electron and atomic force microscopy. The near surface area of samples was also analyzed by diffraction of the backscattered electrons and energy-dispersive X-ray microanalysis. Amorphization of the near-surface layer was observed at the lowest implantation doses of c-Si. Ag nanoparticles were synthesized and uniformly distributed over the near Si surface when the threshold dose of 3.1 × 1015 ion/cm2 exceeded. At a dose of more than 1017 ion/cm2, the formation of a surface nanoporous silicon structure was detected. Ag nanoparticle size distribution function became bimodal and the largest particles were localized along Si-pore walls. In the case of Ge substrates, as a result of the implantation on the c-Ge surface, a porous amorphous PGe layer of a spongy structure was formed consisting of a network of intersecting Ge nanowires with an average diameter of ∼10–20 nm. At the ends of the nanowires, the synthesis of Ag nanoparticles was observed. It was found that the formation of pores during Ag+-ion implantation was accompanied by efficient spattering of the Si and Ge surface. Thus, ion implantation is suggested to be used for the formation of nanoporous semiconductor thin layers for industries, which could be easily combined with the crystalline matrix for various applications.

With the purpose of creating a thin composite layer of Ag:Si containing Ag nanoparticles (NPs), the effect of a nanosecond pulse produced by ruby laser (λ = 0.694 µm) on single-crystal c-Si implanted with a high dose of Ag+ ions is studied. The pulsed laser annealing (PLA) is carried out with an energy density exceeding the melting threshold of amorphous а-Si (W ≥ 1.2 J/cm2). During the PLA, temporal dynamics of reflectivity R(t) of probing laser radiation (λ = 1.064 µm) from the Ag:Si layer is explored and compared to data on the melt existence time obtained by the computer simulation. The morphology of the surface, crystallinity, and spectral optical reflection R(λ) of Ag:Si layers subject to PLA are studied. PLA is found to cause melting and subsequent crystallization of the implanted а-Si with ion-synthesized Ag NPs. In addition, a decrease of the surface roughness from 9 to 3–4 nm and redistribution of Ag NP sizes into two fractions—fine (5–15 nm) and larger (40–60 nm)—are observed. The weakening of plasmon intensity Ag NPs in Si (λmax = 835 nm) is observed in R(λ) spectra of an Ag:Si layer after PLA as compared with the initial implanted surface. This weakening may be caused by a decrease in concentration of Ag atoms in the immediate proximity to the surface as a result of Ag impurity partial diffusion within the melted layer, as well as Ag partial evaporation during the PLA.

A technical approach is proposed for the synthesis of thin porous PGe layers with Ag nanoparticles based on low-energy high-dose implantation of single-crystal c-Ge metal ions. To demonstrate a successes of this technique, we performed an Ag+-ion implantation of a polished c-Ge substrates with an energy of 30 keV at a dose of 1.5⋅1017 ion/cm2 and a current density of 5 μA/cm2. Methods of scanning electron and atomic force microscopy, as well as EDX analysis and electron backscattered diffraction was shown that as a result of the implantation on the c-Ge surface a porous amorphous PGe layer is formed of a spongy structure consisting of a network of intersecting Ge nanowires with an average diameter of ∼10–20 nm. At the ends of the nanowires, the synthesis of Ag nanoparticles is observed. It was found that the formation of pores during Ag+-ion implantation is accompanied by efficient spattering of the Ge surface.

Implantation of high-energy helium ions into crystals of natural colorless diamonds colors them bright yellow, brown, or black, depending on the implantation dose. The nature of the induced fantasy color and crystal-chemical features of the implanted diamonds have been investigated by IR spectroscopy and Raman spectroscopy. It is established that the radiation effect of helium ions on the diamond crystal structure results in the transformation of nitrogen-vacancy centers in its bulk with the formation of new A-type color centers, as well as the formation of carbon nanoclusters with the sp2 hybridization of bonds (which is typical of graphite) in black diamonds.

The possibility of using a new composite material based on porous silicon containing silver nanoparticles and synthesized by means of a unique implantation nanotechnology as an optically sensitive material in biological and chemical sensors is tested experimentally. It is demonstrated that detection of small amounts of the studied organic substance (methyl orange dye) is possible due to the effect of surface-enhanced Raman scattering (SERS) from the molecules affected by the local electromagnetic field of the silver nanoparticles.

We propose a method for the formation of porous germanium (P-Ge) layers containing silver nanoparticles by means of high-dose implantation of low-energy Ag+ ions into single-crystalline germanium (c-Ge). This is demonstrated by implantation of 30-keV Ag+ ions into a polished c-Ge plate to a dose of 1.5 × 1017 ion/cm2 at an ion beam-current density of 5 μA/cm2. Examination by high-resolution scanning electron microscopy (SEM), atomic-force microscopy (AFM), X-ray diffraction (XRD), energy-dispersive X-ray (EDX) microanalysis, and reflection high-energy electron diffraction (RHEED) showed that the implantation of silver ions into c-Ge surface led to the formation of a P-Ge layer with spongy structure comprising a network of interwoven nanofibers with an average diameter of ∼10–20 nm Ag nanoparticles on the ends of fibers. It is also established that the formation of pores during Ag+ ion implantation is accompanied by effective sputtering of the Ge surface.

An amorphous silicon (α-Si) layers formed on the surface of single-crystal substrate (c-Si) by low-dose implantation with silver ions were studied by spectroscopic ellipsometry. Ion implantation of c-Si was carried out with energy of 30 keV, current density varied from 0.1 to 5 μA/cm2 and with doses in the range of 6.24·1012–1.3·1016 ion/cm2. The effect of non-linear increase in the generation rate of radiation defects with a grow of current density was observed and discussed.

Thin ferromagnetic films with the uniaxial magnetic anisotropy were synthesized by Co+ implantation into single-crystal silicon in the magnetic field. It was concluded that the formation of the induced magnetic anisotropy is due to the directional atomic pair ordering (Neel–Taniguchi model). The synthesized films were studied by the ferromagnetic resonance (FMR) method in the temperature range from 100 to 300 K. The FMR linewidth is almost independent of temperature, which is in agreement with the Raikher model describing the magnetic resonance of uniaxial magnetic particles. It is found that the temperature dependence of the anisotropy constant is linear. This dependence can be associated with the difference in the coefficients of thermal expansion of the Si (111) substrate and the ion-beam-synthesized cobalt silicide films.

The article describes the study of Si surface sputtering with the low-energy high-dose implantation by Ag+ ions with energy E = 30 keV and current density J = 8 μA/cm2. The radiation dose was D = 2.5 · 1016–1.5 · 1017 ion/cm2. It was found that the thickness of the spattered Ag:Si layer monotonously increased up to 50 nm when D reached its maximum, and the value of the effective sputtering yield was ~1.6.

The flat monocrystalline c-Ge wafers implanted by 108Ag + ions with the energy E = 30 keV, dose D = 1.3·1016 ion/cm2 and at current density J = 5 μA/cm2 for various substrate temperatures from 25 to 400 °C were studied. By scanning electron microscopy and optical reflection spectroscopy it was found that as a result of ion implantation in the temperature range from 25 to 300 °C an amorphous porous Ag:PGe layers of a spongy structure consisting of Ge nanowires on the c-Ge substrate surface are formed. The diameter of Ge nanowires increases from 16 to 24 nm with a rising of substrate temperature. It is shown that at the highest temperature of 400 °C, the porous structure does not form and the Ge surface remains flat on which the formation of Ag nanoparticles can be observed. A change in the level of the sample surface in dependence on substrate temperature due to swelling up to 280 °C was replaced by effective ion sputtering at higher temperatures.

The new results on the optical reflection of the Si surface layers implanted by silver ions at low energies of 30 keV over a wide dose range from 5.0 × 1014 to 1.5 × 1017 ion/cm2 are presented. As ...

The optical reflection of the surface of silicon implanted with Ag+ ions at low energy of 30 keV in a wide dosage range of 5.0·1014–1.5·1017 ion/cm2 was studied in parallel with electron microscopy observation of the samples. It was found that with increasing ion dose of irradiation, the reflection intensity in the UV range of the Si spectrum decreases monotonically due to amorphization and macrostructuring of Si near-surface layer. In the long-wavelength region of the reflection spectra, a selective band with a maximum near 830 nm is recorded due to the plasmon resonance of ion-synthesized Ag nanoparticles.

The synthesis of porous PGe layers with Ag nanoparticles is considered when implanted with Ag+ ions of single-crystal c-Ge with an energy of 30 keV at a dose of 1.5 × 1017 ion/cm2 and a current density in the ion beam of 5 μA/cm2. Scanning electron and atomic force microscopy, as well as X-ray microprobe analysis and the diffraction of reflected electrons, have shown that, as a result of implantation, a porous amorphous PGe layer of a spongy structure consisting of a grid of intersecting nanofilaments with an average diameter of ~10–20 nm is formed on the c-Ge surface. At the ends of the filaments, the formation of Ag nanoparticles is observed. It is found that the formation of pores during implantation with Ag+ ions is accompanied by the effective spraying of the Ge surface.

Modification of the surface layers of polyimide films under γ-radiation and implantation with 30–100 keV Ni, Mn, Ag, Co, Fe and B ions in the dose range of 10¹⁵–1.5 × 10¹⁷ cm^–2 are investigated by reflection spectra measurements. Ion implantation is shown to lead to the modification of reflection from the rear (unimplanted) polymer side. Depending on the kind of ion and implantation mode a strong increase in the integrated reflection coefficient in the polymer opacity range is observed, as well as growth of the reflection intensity of optical bands λ1 = 254 and λ2 = 311 nm and their shifts to the short-wavelength region. The change in the reflection coefficient far beyond the implanted region is caused by the radiation-induced transformation of the polymer supermolecular structure near the surface and the relaxation of mechanical stress formed during film production.

Comparative analysis of the structural and optical properties of composite layers fabricated with the aid of implantation of single-crystalline silicon (c-Si) using Ge+ (40 keV/1 × 1017 ions/cm2) and Ag+ (30 keV/1.5 × 1017 ions/cm2) ions and sequential irradiation using Ge+ and Ag+ ions is presented. The implantation of the Ge+ ions leads to the formation of Ge: Si fine-grain amorphous surface layer with a thickness of 60 nm and a grain size of 20–40 nm. The implantation of c-Si using Ag+ ions results in the formation of submicron porous amorphous a-Si structure with a thickness of about 50 nm containing ion-synthesized Ag nanoparticles. The penetration of the Ag+ ions in the Ge: Si layer stimulates the formation of pores with Ag nanoparticles with more uniform size distribution. The reflection spectra of the implanted Ag: Si and Ag: GeSi layers exhibit a sharp decrease in the intensity in the UV (220–420 nm) spectral interval relative to the intensity of c-Si by more than 50% owing to the amorphization and structuring of surface. The formation of Ag nanoparticles in the implanted layers gives rise to a selective band of the plasmon resonance at a wavelength of about 820 nm in the optical spectra. Technological methods for fabrication of a composite based on GeSi with Ag nanoparticles are demonstrated in practice.

The present work concerns the fabrication and the investigation of Ag nanoparticles, surface embedded in the pulsed laser deposition (PLD) grown ZnO thin films. The third-harmonic Nd:YAG laser is used for PLD of ZnO thin films. The ion implantation technique for Ag doping in ZnO matrix is used. The morphology, texture and composition of the samples are investigated. The Ag distribution in the implanted near-surface region is investigated as a function of the processing conditions. The influence of the substrate temperature and ambient oxygen pressure during the PLD growth of ZnO films is studied. The applied processing parameters during the deposition of ZnO thin films lead to different microstructure of ZnO host matrix and have a significant impact on the properties of subsequently produced Ag/ZnO nanocomposites. The changes of optical surface plasmon resonance (SPR) band of synthesized Ag nanoparticles for different morphologies are analyzed for implanted samples. The composite nanostructures are found to exhibit SPR absorption properties of metal nanoparticles after the ion implantation, especially pronounced for the samples with laser grown ZnO matrix at high substrate temperatures. This study demonstrates how the different crystal structure of the ZnO supporting material, influences the Ag implantation process and, respectively, the properties of the produced Ag/ZnO nanocomposites.

The study addresses the monocrystalline c-Ge substrates implanted by Ag+ ions with the energy of 30 keV, irradiation dose of 7.5·1016 ion/cm2 at current density of 8 μA/cm2 and annealed by incoherent-light pulse. By scanning electron microscopy and optical reflection spectroscopy measurements it was shown that after ion implantation an amorphous porous Ag:PGe layer of a spongy structure with nanowires on the c-Ge substrate were formed. Pulsed light annealing of the implanted samples leads to partial melting and recrystallization of the surface Ag:PGe layer. The spongy annealed structure of the Ag:PGe layer was not destroyed, however the diameters of nanowires increased by about 1,5 times.

Multilayer systems consisting of layers of hybrid quantum dots are fabricated. The quantum dots with the CdSe/CdS core/shell structure are chemically synthesized and deposited on the surface of quartz glass that contains ion-synthesized silver nanoparticles in the near-surface region. Silver nanoparticles exhibit optical absorption owing to the localized surface plasmon resonance. Variations in the photoluminescence intensity of the layer related to an increase in the distance from the quartz surface with metal nanoparticles are studied. An increase in the photoluminescence intensity is observed under excitation in the spectral region of the plasmon absorption of silver nanoparticles. An optimal distance between the layers is determined to maximize the enhancement of the photoluminescence of quantum dots in the presence of the near field of metal nanoparticles.

We study the characteristics of the luminescence of composite films based on polymethyl methacrylate with CdSe quantum dots deposited from solution onto the surface of a sapphire substrate containing a preliminarily formed layer with ion-synthesized silver nanoparticles. The sapphire layer with silver nanoparticles exhibits selective plasmon absorption in the visible spectral range with a peak at 463 nm. Enhancement in the exciton luminescence intensity of quantum dots with a peak at 590 nm is observed upon excitation at wavelengths lying in the region of plasmon resonance of metal nanoparticles, as well as luminescence quenching for quantum dots located in the vicinity of silver nanoparticles.

40 keV iron ions have been implanted into single-crystal silicon wafers at room temperature. As a result, thin iron-silicide films were synthesized in the near-surface region of substrates. Scanning magnetooptical Kerr effect studies showed that some films had the uniaxial magnetic anisotropy. The coercive force determined in the direction of the easy magnetization for films with the magnetic anisotropy increased with the increase in the implantation fluence. However, ferromagnetic samples became isotropic when the dose of the order of 2.6×1017 cm–2 was reached. Ferromagnetic resonance studies showed that the resonance linewidth in isotropic samples increased with the temperature decrease. It was found that the ferromagnetic resonance linewidth for samples with the uniaxial anisotropy was less than that for isotropic ones. The observed behavior of resonance spectra can be explained on the basis of the model taking into account the effect of thermal fluctuations of the resonance line shape in disperse ferromagnets.

Amorphous silicon (a-Si) produced on surfaces of single-crystal substrates (c-Si) by low-energy low-dose implantation of silver ions is studied by spectral ellipsometry and electron backscatter diffraction. Implantation was done with an ion energy of 30 keV at a constant ion beam current density of 2 μA/cm2 and doses of 6.24·1012–1.25·1016 ions/cm2 on room temperature substrate targets. Irradiation was carried out with a current density of 0.1–5 μA/cm2 for implantation doses of 6.24·1013 and 1.87·1014 ions/cm2. It was found that spectral ellipsometry is an accurate andreliable method for monitoring low-dose ion implantation processes.

We propose to form optical diffractive elements on the surface of poly(methyl methacrylate) (PMMA) by implanting the polymer with silver ions (E = 30 keV; D = 5.0 × 1014 to 1.5 × 1017 ion/cm2; I = 2 μA/cm2) through a nickel grid (mask). Ion implantation leads to the nucleation and growth of silver nanoparticles in unmasked regions of the polymer. The formation of periodic surface microstructures during local sputtering of the polymer by incident ions was monitored using an optical microscope. The diffraction efficiency of obtained gratings is demonstrated under conditions of their probing with semiconductor laser radiation in the visible spectral range.