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  1. 33 Acta Physica Polonica A

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  1. 3 Komarov F.

  2. 3 Milchanin O.

  3. 3 Mudryi A.

  4. 3 Potera P.

  5. 3 Vlasukova L.

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1
Content available remote

Radiation Damage Centers in Cholesteryl Heptanoate

100%
Sayin U., Can C., Türkkan E., Dereli Ö., Ozmen A., Yüksel H.
Acta Physica Polonica A
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2013
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vol. 124
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issue 1
70-73
EN
Cholesterol takes part significantly in many biological mechanisms and as important component for manufacture of bile acids, steroid hormones, and several fat-soluble vitamins. To determine magnetic properties of cholesteryl heptanoate (C_{34}H_{58}O_2) which is an important cholesteryl ester in human life and new technology, the single crystals of cholesteryl heptanoate were grown by slow evaporation of concentrated ethyl acetate solution and the grown single crystals were irradiated at room temperature with ^{60}Co γ ray. The radical produced by gamma irradiation has been investigated in the range of temperatures 123-330 K for different orientations of the crystal in a magnetic field by EPR. Radiation damage center was attributed to radical ĊH_α CH_{2β}. The g factor and hyperfine coupling constants have slight dependence on temperature and evident dependence on the orientation of the magnetic field. Determined g factor and hyperfine coupling constants for the radical ĊH_α CH_{2β} were found to be anisotropic with the average values g_{av}=2.0036, (a_{CH_α})_{av}=14.52 G, (a_{CH_{2β}})_{av}=25.78 G.
2
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Lattice Deformation in Al_{x}Ga_{1-x}As Epitaxial Layers Caused by Implantation with High Doses of 1 Mev Si Ions

63%
Wieteska K., Wierzchowski W., Graeff W., Turos A., Grötzschel R.
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vol. 96
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issue 2
289-293
EN
A series of highly perfect Al_{0.45}Ga_{0.55} As epitaxial layers implanted with 1 MeV Si ions to the doses in a range 7×10^{13}-2×10^{15} ions/cm^{2} were studied with various conventional and synchrotron X-ray diffraction methods. The presently used methods allowed both the measurement of lattice parameter changes and strain induced deformation. The evaluation of complete strain profiles was also performed by numerical simulation of diffraction curves. It was found that the implantation induced considerable change of lattice parameter reached the maximum at the dose 3×10^{14} ions/cm^{2}. The recorded curves proved also that the lattice parameter is almost constant in the near surface region of the implanted layers. The applied doses did not cause lattice amorphisation at room temperature.
3
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Effect of High Energy Ion Implantation on the Structure and Mechanical Properties of Aluminium Alloys

63%
Anishchik V., Poliak N., Ponaryadov V., Opielak M., Boiko O.
Acta Physica Polonica A
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2017
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vol. 132
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issue 2
291-294
EN
The effect of implantation of Ne⁺, Kr⁺, and Bi⁺ ions over the energy range 26-710 MeV on the structural-phase state and the mechanical properties of the aluminum-based alloys (Al-Cu, Al-Cu-Mg, Al-Cu-Zn, Al-Mn) was studied. The revealed peculiarities of variations in the structure, phase composition, and mechanical properties of aluminum alloys are attributed to the electron deceleration of ions making the principal contribution to the formation of radiation defects which enhance the diffusion processes in the targets.
4
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Materials Modifications with Cluster Beams: Bulk and Surface Modification

63%
Dunlop A.
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vol. 96
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issue 2
181-195
EN
It is now well accepted that electronic excitation and ionization arising from the slowing down of swift heavy ions can lead to structural modifications in some metallic targets as it has been known for a long time in insulators. A rapid overview of some results obtained after GeV monoatomic heavy ion irradiations will be given. It will then be shown that new specific effects take place during irradiations with cluster ions. The projectiles used are energetic cluster beams: 10 to 40 MeV Au_{4} or C_{60} ions. The rates of linear energy deposition in electronic excitation are close for GeV monoatomic and for 10 MeV cluster ions, but the cluster ions have characteristic velocities which are one order of magnitude smaller than those of monoatomic ions. This leads to a strong spatial localization of the deposited energy during the slowing down process. The density of deposited energy can then reach values as high as a few 100 eV/atom. This very high density of energy deposited in the electronic system of the targets can lead to spectacular structural modifications: generation in the vicinity of the ion trajectories of isolated or agglomerated point defects, new crystalline phases, amorphized regions... After an overview of such damage induced in bulk metals, semiconductors, and insulators, we will discuss surface damage, consisting in the formation of bumps, craters, "lava-flows" on the target surface.
5
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New Possibilities of Swift Heavy Ion Implantation in Material Science and Technology

63%
Słowiński B.
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vol. 96
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issue 2
239-244
EN
We summarise briefly the advantages of swift heavy ions (≈ 1 MeV/u) application to analysis and treating of solids in order to modify their properties. As an illustration some examples of this application are quoted.
6
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Lattice Deformation Studies in Silicon Implanted with High-Energy Protons

63%
Wieteska K., Dłużewska K., Wierzchowski W.
Acta Physica Polonica A
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1996
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vol. 89
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issue 3
395-400
EN
The deformation of crystal lattice in silicon implanted with protons of energy 1.6-9 MeV was studied by means of X-ray topography and double-crystal rocking curve measurements. The samples were investigated as-implanted and after thermal and electron annealing. The surface relief of the implanted part of the crystal was also revealed with optical methods. As-implanted wafers exhibited spherical bending being convex at the implanted side. Thermal and electron annealing caused a dramatic increase in bending of the implanted part while the bending of the remaining part of the sample was reduced. A characteristic behaviour of a double-crystal topographic contrast in the annealed crystals was explained due to bending of the shot-through layer along the Gaussian profile.
7
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Interference Fringes in Synchrotron Section Topography of Implanted Silicon with a Very Large Ion Range

63%
Wieteska K., Wierzchowski W., Graeff W., Dłużewska K.
Acta Physica Polonica A
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1997
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vol. 91
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issue 5
1021-1024
EN
Silicon crystals implanted with 9 MeV protons to the dose of 5×10^{17} cm^{-2} were studied with X-ray topographic methods using both conventional and synchrotron radiation sources. After the implantation the crystals were thermally and electron annealed. The implantation produced large 600 μm thick shot-through layer while the total thickness of the samples was 1.6 mm. It was confirmed by means of double crystal topography that the whole crystal was elastically bent. The transmission section patterns revealed both parts of the implanted crystal separated by strong contrasts coming from the most damaged layer and distinct interference fringes which appeared on one side of the topograph only. The location of the fringes changed when the beam entered the other side of the sample. The mechanism of fringe formation was studied with numerical integration of the Takagi-Taupin equations, especially studying the intensity distribution in the diffraction plane. The simulations reproduced the location of the fringes in different geometries and indicate that they can be caused both by variable crystal curvature and variable ion dose.
8
Content available remote

Long-Range Effect in Ion-Implanted Titanium Alloys

51%
Budzynski P., Sielanko J.
Acta Physica Polonica A
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2015
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vol. 128
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issue 5
841-844
EN
Surface modification of titanium alloy (Ti6Al4V) by nitrogen ion implantation and ion beam-assisted deposition (C, N) was investigated. The depth distribution of implanted nitrogen atoms was analysed using the Rutherford backscattering technique. Nitrogen implantation reduces the coefficient of friction and wear. A better effect can be obtained when nitrogen implantation is combined with carbon deposition. Based on the changes in the coefficients of friction and wear as well as profilograms of wear tracks, the improvement of the tribological properties was found at a depth exceeding nearly 5 times the range of the implanted nitrogen ions. Identification of the long-range effect for Ti6Al4V alloy was performed on the basis of tribological analyses. This study is a continuation of research conducted for AISI 316L and H11 steel.
9
Content available remote

Study on the Breakdown Mechanism of Fabrication of Micro Channels in Fused Silica Substrates with ps Laser Pulses

51%
Li S., Bai Z., Qin S.
Acta Physica Polonica A
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2013
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vol. 123
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issue 1
67-72
EN
A new microchannel fabrication technology for fused silica substrate is presented. A mode-locked laser was used to fabricate straight microchannels in a fused silica substrate by laser plasma-induced plasma. The depth of the channels is up to 5 mm and there are no thermal cracks around the channel. We studied the ionization mechanism of optical breakdown formed by laser pulses and discussed the optical breakdown threshold. A mechanism is proposed to explain the formation of the microchannels and the characteristics of the microchannels are analyzed through the laser pulse characteristics.
10
Content available remote

Effect of High Energy Electron Irradiation on Structure and Optical Properties of ZnO Films

51%
Myroniuk D., Lashkarev G., Shtepliuk I., Lazorenko V., Maslyuk V., Timofeeva I., Romaniuk A., Strelchuk V., Kolomys O., Khomyak V.
Acta Physica Polonica A
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2013
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vol. 124
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issue 5
891-894
EN
Zinc oxide films were grown on sapphire substrates by direct current magnetron sputtering and irradiated by electrons with energy 10 MeV and fluences 10^{16} and 2 × 10^{16} cm^{-2}. As-grown and irradiated samples were investigated by X-ray diffraction and photoluminescence spectroscopy. It was found that radiation causes the appearance of complex defects, reducing the size of coherent scattering regions and the increase of the defect PL band.
11
Content available remote

Ion Beam Synthesis of InAs Nanocrystals in Si: Influence of Thin Surface Oxide Layers

51%
Komarov F., Vlasukova L., Milchanin O., Greben M., Komarov A., Mudryi A., Wesch W., Wendler E., Zuk J., Kulik M., Ismailova G.
Acta Physica Polonica A
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2013
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vol. 123
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issue 5
809-812
EN
Nanosized crystallites have been synthesized in the Si and SiO_2/Si structures by means of As (170 keV, 3.2 × 10^{16} cm^{-2}) and In (250 keV, 2.8 × 10^{16} cm^{-2}) implantation at 25C and 500C and subsequent annealing at 1050C for 3 min. The Rutherford backscattering, transmission electron microscopy, and photoluminescence techniques were used to analyse the impurity distribution as well as the structural and optical characteristics of the implanted layers. It was found that oxidation of samples before thermal treatment significantly reduced the As and In losses. A broad band in the region of 1.2-1.5 μm was detected in the photoluminescence spectra. The highest photoluminescence yield for the samples after "hot" implantation and annealing was obtained. Anodic oxidation of the implanted samples before annealing results in the additional increase of photoluminescence yield.
12
Content available remote

Formation of Multilayered Ti-Hf-Si-N/NbN/Al_2O_3 Coatings with High Physical and Mechanical Properties

51%
Pogrebnjak A., Prozorova M., Kovalyova M., Kolisnichenko O., Beresnev V., Oyoshi K., Takeda Y., Kaverina A., Shypylenko A., Partyka J.
Acta Physica Polonica A
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2013
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vol. 123
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issue 5
813-815
EN
This work presents the first results on forming of multi-layered superhard coatings Ti-Hf-Si-N/NbN/Al_2O_3 and their properties as well as structure. Microstructure, elemental and phase compositions of multi-layered coatings obtained by different methods were investigated. There were used such methods as: scanning electron microscopy EDS JEM-7000F microscope (with microanalysis) for research of cross-section of coatings, with subsequent Auger-electron spectroscopy, X-ray diffraction analysis, optical inverted microscope Olympus GX51, electron-ion microscopes Quanta 200 3D and Quanta 600 (scanning electron microscopy), equipped by the detector of X-ray radiation of the system PEGASUS 2000. It was stated that hardness of coatings has reached 56 GPa, and at the same time the factor of wearing during friction was the smallest - 2.571×10^{-5}. It was also noted that nitrogen pressure in the chamber at the deposition of the top layer significantly influences on the properties of samples. For example, the coefficient of friction at P=0.3 Pa from 0.2 at the beginning of track to 0.001 (during the tests), and at the pressure of nitrogen P=0.8 Pa, the coefficient of friction was equal to 0.314 at the beginning of track and 0.384 at the end (during the tests).
13
Publication available in full text mode
Content available

The Influence of the Defect Structure on the Nitriding of Fe by PIII

51%
De Baerdemaeker J., Jirásková Y., Schaaf P., Segers D., Dauwe C.
Acta Physica Polonica A
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2005
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vol. 107
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issue 5
817-820
EN
Plasma ion immersion implantation is a promising technique for nitriding. A case study of the characterization of the plasma ion immersion implantation nitriding of iron alloys is the plasma ion immersion implantation nitriding of pure Fe. A set of Fe samples of 99.98% purity and with different defect structure was plasma ion immersion implantation nitrided at different temperatures. Depth profiling of the samples was achieved using positron annihilation spectroscopy with a slow positron beam and nanoindentation. A correspondence was found between the line shape parameter S and the hardness of the plasma ion immersion implantation treated samples.
14
Content available remote

Properties of Neutron Doped Multicrystalline Silicon for Solar Cells

51%
Pochrybniak C., Pytel K., Milczarek J., Jaroszewicz J., Lipiński M., Piotrowski T., Kansy J.
Acta Physica Polonica A
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2008
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vol. 113
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issue 4
1255-1265
EN
The technology of neutron transmutation doping of silicon wafers in MARIA nuclear research reactor is described. The studies of the radiation defects performed with positron annihilation confirmed that divacancies dominate in the irradiated material. Thermal treatment of irradiated silicon at 700-1000°C produces void-phosphorus complexes and void aggregates. The resistivity of the samples produced by neutron transmutation doping was found to be uniform within 2.5% limits. The severe reduction of the minority carrier lifetime in irradiated samples was confirmed.
15
Content available remote

Environmental Gamma Dose Evaluation During Explosive Materials Analysis by PGNAA Technique Using MCNPX Code

51%
Nasrabadi M., Omidi S.
Acta Physica Polonica A
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2015
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vol. 127
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issue 4
961-964
EN
Increased use of radiation in medicine, industry, and laboratories, requires safe conditions to be provided for its optimal use. One of the cases in which people are exposed to radiation, is during the detection of explosive materials by PGNAA method. Therefore, external dosimetry is necessary for workplaces where the method is used. In this study, Monte Carlo simulation program, MCNPX has been used to simulate gamma dose in the environment during the detection of explosive materials by PGNAA method. The simulated results were validated practically. The results indicate a good agreement between the simulated and measured data. The study demonstrated that MCNPX code can be used effectively for simulating gamma dose in various environments.
16
Content available remote

Ion Irradiation Studies of Soft Magnetic Metallic Glasses

51%
Pavlovič M., Miglierini M., Mustafin E., Seidl T., Ensinger W., Strašík I., Šoka M.
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|
issue 5
754-755
EN
Finemet and Vitrovac® 6025 metallic glasses were irradiated by light (N) and heavy (Au and Ta) ions at different energies from 110 keV to 250 MeV/u (MeV per mass unit) and fluences from 1 × 10^{11} ions/cm^2 to 1 × 10^{17} ions/cm^2. They were analysed by the Mössbauer spectrometry and magnetic susceptibility measurements. Qualitative differences were observed between the radiation effects caused by light and heavy ions.
17
Content available remote

Phase Transformations in Pyrochlores Irradiated with Swift Heavy Ions: Influence of Composition and Chemical Bonding

51%
Sattonnay G., Thomé L., Sellami N., Monnet I., Grygiel C., Legros C., Tetot R.
Acta Physica Polonica A
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2013
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vol. 123
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issue 5
862-866
EN
Gd_2Ti_2O_7 and Gd_2Zr_2O_7 pyrochlores were irradiated with swift heavy ions in order to investigate the effects of the chemical composition on the structural changes induced by high electronic excitation. The XRD results show that the structural modifications induced by irradiation with 93 MeV Xe ions are strongly dependent on the sample composition: Gd_2Ti_2O_7 is readily amorphized, whereas Gd_2Zr_2O_7 is transformed into a radiation-resistant anion-deficient fluorite structure. Atomistic simulations with the second-moment tight-binding QEq model allow us to calculate the lattice properties of both Gd_2Ti_2O_7 and Gd_2Zr_2O_7, and also to quantify the degree of covalency and ionicity in these compounds. These calculations clearly show that Gd_2Ti_2O_7 is more covalent than Gd_2Zr_2O_7, thus confirming that the amorphization resistance can be related to the covalent character of insulators.
18
Content available remote

Influence of Xe^{+} Irradiation on Topography and Wettability of Graphite Surface

51%
Tashlykov I., Turavets A., Zhukowski P.
Acta Physica Polonica A
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2011
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vol. 120
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issue 1
115-117
EN
The investigation of influence of Xe^{+} ions irradiation of graphite on its surface topography and wettability was conducted. With the increase of the irradiation dose, the roughness average increases rapidly at first (when the sample was irradiated at the dose of 1 × 10^{14} cm^{-2}) and then decreases slowly. The atomic force microscopy three-dimensional pictures showed that after irradiation of graphite of Xe^{+} ions with a dose of 3 × 10^{15} cm^{-2} hemispherical grains (from 0.2 to 0.8 μm in diameter) appear on its surface. Surface water contact angle measurement showed that irradiation of graphite by Xe^{+} ions leads to a hydrophobic surface of graphite. We have observed that irradiation of graphite by Xe^{+} ions can be used for obtaining graphite surface with desirable topography and water wettability.
19
Content available remote

Influence of Annealing and Irradiation by Heavy Ions on Optical Absorption of Doped Lithium Niobate Crystals

51%
Potera P., Stefaniuk I.
Acta Physica Polonica A
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2016
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vol. 130
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issue 3
800-804
EN
The present work is devoted to investigation of optical absorption changes in Fe and Cu doped LiNbO₃ (LNO) single crystals induced during annealing in vacuum and air as well as under influence of the ²⁰⁹Bi ions irradiation with energy 11.4 MeV/u (MeV per nucleon) and a fluence 5×10¹¹ cm¯² at room temperature. The analysis of changes of absorption of the crystal during air annealing have been studied in the Arrhenius coordinates and activation energies have been determined.
20
Content available remote

Structure and Optical Properties of Silicon Layers with GaSb Nanocrystals Created by Ion-Beam Synthesis

51%
Komarov F., Vlasukova L., Milchanin O., Mudryi A., Dunetz B., Wesch W., Wendler E., Karwat C.
Acta Physica Polonica A
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2011
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vol. 120
|
issue 1
87-90
EN
We have studied the ion-beam synthesis of GaSb nanocrystals in Si by high-fluence "hot" implantation of Sb and Ga ions followed by thermal annealing. The Rutherford backscattering, transmission electron microscopy/transmission electron diffraction, Raman spectroscopy and photoluminescence were used to characterize the implanted layers. It was found that the nanocrystal size increases from 5 to 60 nm in the samples annealed at 900°C up to 20-90 nm in those annealed at 1100°C. For the samples annealed at 900°C a broad band in the region of 0.75-1.05 eV is registered in the photoluminescence spectra. The nature of this photoluminescence band is discussed.
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