FCSS, .8, 2, 2007


G.O. Sukach1, V.V. Kidalov2, A.S. Revenko2, V.M. Chobanyuk3, D.M. Freik3

Physical and Chemical Aspects of Substrate Materials for the Epitaxial
Growing GaN Films (Review)

1State University of Information-Communication Processing Techniques, 7, Solomyanska Str, Kyiv, Ukraine
2Berdyansk State Pedagogical University, 4, Shmidta Str, Berdyansk, Ukraine
3Physics and Chemistry of Solid State Department, Vasiliy Stefanyk Precarpathian National University, 201, Galytska Str., Ivano-Frankivsk, 76000, Ukraine

The comparative analysis of influencing of physical and chemical properties of substrate materials which use for the epitaxial growing GaN thin films, on the structurally morphological, electro-physical, crystallographies optical and other parameters and characteristies of such films are lead. Except for the know substrates, such, as a sapphire, 6-SiC, Si, GaAs, and AlN, especially attention is spared the porous substates on the basis of Si and GaAs, which in the last few years became perspective material for the receipt of GaN thin layers of the promoted structural perfection both hexagonal and cube modifications.

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A.V. Konstantinovich1, I.A. Konstantinovich2

The Radiation Spectrum of Four Electrons which Move in a Spiral in a Transparent Medium

1Chernivtsi National University, Kotsybynsky Str.,2, Chernivtsi, 58012, Ukraine,
E-mail:theormyk@chnu.cv.ua; aconst@hotbox.ru
2Institute of Thermoelectricity NAS and MES of Ukraine, Dubinska Str., 9a, Chernivtsi, 58027, Ukraine

By the improved Lorentzs self-interaction force method the spectral distribution of the average radiation power of a system of electrons, which move in magnetic field are consistently investigated. For the first time we have obtain and studied the fine structure for the radiation spectrum of four non-interacting electrons which move one by one along a spiral in transparent medium.

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A.E. Kiv1, R.M. Balabay2, E.Yu. Chernonog2

Calculations of Electron Structure of Silicon with Hydrogen Concentration Higher its Limit Solubility

1Ben-Gurion University of the Negev, Mater. Eng. Dept., Beer Sheva, 84105 Israel,
2State Pedagogical University, Department of Physics, 54 Prospect Gagarina, Krivoy Rog, 50086,
Ukraine E-mail:charly-15@mail.ru

Dihydride complexes in crystal silicon with concentration > 1021cm-3 are theoretically explored. The electronic structure and energetic characteristic are studied by the electron density functional method and the first-principle psevdopotential. It is shown that the energetic advantageous Si-H-H-Si configuration, which stabilize of the crystal silicon towards the atomic reconstruction.

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Ya.S. Budzhak1, D.M. Freik2, O.L. Ilkiv2

Temperature Description of Conductivity Doped Crystals of Semiconductors

1UkraineNational University Lvivska Politekhnika 12 S. Bandery Str, Lviv-13, Ukraine 2Vasyl Stefanyk Precarpathion National University, 57 Shevchenko Str., Ivano-Frankivsk, Ukraine

In work had been analytically explored influence of doping on temperature dependence of reverse ohmic resistance of crystal, which is named him by conductivity. Conductivity of dope crystal of n-type of conductivity in the interval of temperature (20-300) K is considered. Substantiated method which enables by temperature descriptions of conductivity to define the concentrations of alloying dope, energy of activating of donors and to draw quantitative conclusions about the mechanisms of dispersion and mobility of current carrier in the explored crystal.
Key words: energy of activating, drift mobility, doping, conductivity.

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H.J. El-Khozondar1, M.M. Shabat2,3, G. Abu Tair2, and M. Abadla4

Thermal-Stress effects on nonlinear thin film Waveguide Sensors

1Department of Electrical and computer Engineering, IUG, Gaza, Gaza Strip, Palestinian Authority
2Physics Department, IUG, Gaza, Palestinian Authority
3Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Str.38, 01187, Dresden, Germany
4Alaqsa University, Gaza, Gaza Strip, Palestinian Authority, e-mail:mazen@alaqsa.edu.ps

We analyze the modelling of nonlinear waveguide sensors. The effect of thermal-stress on the optical performance of nonlinear symmetrical sensor is studied. The mathematical forms of the dispersion equation and thermal stress sensitivity are analytically derived and plotted numerically. It is found that the thermal sensitivity of the sensor can be controlled by tuning the core size, by changing loading materials, and by carefully selecting the materials.
Key words: nonlinear, optical sensor, thermal effect, thermal sensitivity, thermal stress.

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T.S. Kulay

About a Frequency Dependence of Conductivity e-Ag2CdI4 in far Infrared Range of Spectrum

National UniversityLvivska Politechnika, S. Bandery str., 12, 79013, Lviv, Ukraine, e-mail:taras_kulaj@yahoo.co.uk

Far IR reflections spectra and Raman spectra of a e-Ag2CdI4 at room temperature were investigated. In this article a frequency dependence of conductivity e-Ag2CdI4 was counted. Thus influencing of sublattice CdI42- on conductivity of ions Ag+ was studied.

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O. Vlasenco1, S. Levytskyi2, Ts. Kryskov2

Influence of Admixture on the Termoelectric Properties of PbTe

1V. Lashkoryov Institute of Semiconductor Physics, prospect Nauki, 41, Kyiv, 03028, Ukraine E-mail: levytskyi@ua.fm
2Kamyanets-Podilsky State University, Ogienko Str. 61, Kamyanets-Podilsk, 32300, Ukraine

The influence of impurity on a type of conductivity of connections and change of factor thermo MF from contents of an impurity is investigated. The received results testify that samples PbTe (Ge) and PbTe (Cd2) have a different type of conductivity - in one part a n-type, and in another - -type. At research of samples PbTe (Se), PbTe (In), PbTe (InSe) have received a proof -type of conductivity.
Key words: thermoelectric materials, thermo EMF, PbTe.

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B.K. Ostafiychuk, V.M. Pylypiv, V.O. Kotsyubynsky,V.D. Fedoriv, O.O. Grygoruk

The Transformation of Yttrium Iron Ferrite-Garnet Films Magnetic Microstructure after Phosphorus Implantion and Annealing

Vasyl Stefanyk Precarpathion National University, 57 Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine

The magnetic microstructures changes together with the intracrystal electric fields transformations in phosphorus implanted (E = 65 kV, D = 5·1014, 1,8·1015, 1·1016 m-2) epitaxial yttrium iron garnet films on the base of Mëssbauer spectroscopy datas are investigated. The presence of two magnetic nonequivalent positions of tetra-coordinated Fe3+ and tetra-coordinated paramagnetic Fe2+ are detected. The space orientations of different sublattices magnetic moments are calculated; the dynamic of orientations changes are considered. The causes of Mëssbauer spectras parameters changes after implantation and annealing are discussed.
Key words: yttrium iron garnet, ion implantation, radiation defects, Mëssbauer spectroscopy.

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N.L. Dmitruk, O.I. Mayeva, S.V. Mamykin, V.I. Minko, A.V. Korovin, M.V. Sosnova

Optical Properties of Gold 1D Nanowires Fabricated by Holographic Method on
Flat Dielectric Substrates

Institute for Physics of Semiconductors NAS of Ukraine, 41 prosp. Nauki, 03028, Kyiv,
Ukraine Tel: +(380 44) 525 65 46, Fax: +(380 44) 525 83 42 -mail: sosnova@isp.kiev.ua

The optical properties of gold 1D nanowires on flat dielectric substrate have been studied. The experimental samples were fabricated by holographic method. Modeling and analysis of optical (spectral and angular) characteristic (scattering and extinction) was carried out in the framework of differential formalism. This method allows to consider the excitation and interaction of different types of systems own electromagnetic mode. Good coincidence between theory and experiment was obtained.
Key words: nanowires, surface plasmon resonance, local exitation.

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B.S. Dzundza

Features of Charge Carrier Scattering in Lead Telluride Epitaxial Films

Physics and Chemistry of Solid State Department of the Vasyl Stefanyk Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine, E-mail:fcss@pu.if.ua

Mechanisms of charge carrier scattering in epitaxial films PbTe that deposition precipitated on fresh of (111) crystals chop of NaCl are explored. It is shown, that dominant role has the scattering of discrepancies dislocations on boundary "film-substrate".

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B.T. Boyko, G.I. Kopach, D.A. Kudiy, G.S. Khrypunov

Optical and Structural Properties CdS Films, which Received by the Thermal Evaporation

National technical universityKharkiv polytechnic institute, Kharkiv, 21 Frunze Street, 61002

The structural and optical properties CdS films, which received by the thermal evaporation method, are investigated. The structural parameters are determined by the X-Ray difractogram method, which the definition of dispersion cogerent areas and microdeformations were defined by analytical processing X-Ray difractogram. The mathematical processing of CdS layers transmittion specters are carried out. The crystal structure and optical properties investigated CdS films are defined by the thickness and annealing modes CdS layer.
Key words: method of vacuum thermal evaporation, X-Ray difractogram method, dispersion cogerent area, microdeformations.

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A. Z. Evmenova1, V. A. Odarych2, F. F. Sizov1, M. V. Vuichyk1

Ellipsometric Investigation of CdTe Films on CdHgTe

1V. E. Lashkariov Institute of Semiconductor Physics NAS of Ukraine, pr. Nauky, 45, Kyiv, Ukraine,
03028; phone:+380676021561; e-mail:evmenova_a@ukr.net
2Taras Shevchenko Kyiv National University, physical department, pr. Glushkova, 2,
Kyiv, Ukraine, 03022, e-mail:wladodarych@narod.ru

Refractive index, absorptive index and film thickness of CdTe films obtained on the CdHgTe substrate by the hot-wall epitaxy were detected by the specially developed method. Ellipsometric measurements were conducted on several wave-length of the visible spectrum. Method is based on measuring two ellipsometric parameters of light beam that reflects from several areas with different thickness of the same film or from several films with different (unknown) thickness but of the same material. It was determine that film refractive index (2,6 on average) is on 7% less than that of monocrystalline CdTe. Dispersion of thickness and refractive index was studied. It was supposed that small refractive index is explained by the morphology of films surface.

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.O. Galuschak2, Yu.V. Klanichka1, G.D. Mateik2, O.L. Sokolov1, Ya.S. Yavorsky1

Influence of Oxygen is on the Processes of Degradation of Physical and
Chemical Properties of Lead Selenide Films

1 Vasyl Stefanyk Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine, E-mail:freik@pu.if.ua
2 Ivano-Frankivsk National University of the oil and gas, 15, Karpatska Str., Ivano-Frankivsk, 76000, Ukraine

The results of researches of chemical and phase composition are resulted, and also electric properties of polycrystalline thin films of lead selenide, given influencing of atmospheric oxygen. The mechanisms of co-operation of oxygen with material of films are offered.
Key words: thin films, lead of selenid, oxygen, structure, electrical properties.

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B. Yatsyshyn1,3, D. Freik1, Yu. Gorelenko2, O. Mykolajchuk2, H. Bajtsar2

Magnetic and Electrical Properties Amorphous and Nanocrystalline
RE-Transition Metal-Semiconductor Thin Films

1Vasyl Stefanyk Precarpathion National University, 57 Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine
2Ivan Franko National University, 8, Kyryla and Mefodiya Str., 79005, Ukraine
3Lviv Commercial Academy, 10, Tugan-Baranovskogo, Str, Lviv, 79008, Ukraine

The changes in electroconductivity and magnetic properties amorphous and nanocrystalline RE (Sc, La, Y)-Fe-Ge thin films, received by methods thermal evaporation, are investigated. The dependence of structure and transport properties thin films from growth rate, chemical structure both subsequent temporary and thermal processing is revealed.

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D.I. Bletskan1, V.P. Ivanitsky2, V.S. Kovtunenko3

Micro- and Nanostructure of Ge-Se Amorphous Films

1Physics Department, Uzhgorod National University, Voloshyn Str. 54, 88000 Uzhgorod, Ukraine
2Technical Engineering Departament, Uzhgorod National University, Capitulna Str. 13, 88000 Uzhgorod, Ukraine
3Cherkasy Technology University, Shevchenko Boulevard 460, Cherkasy, Ukraine ivanc@mail.uzhgorod.ua

In this paper we report the electron microscopic results of the study of a micro- and nanostructure of Ge-Se amorphous films. Are found nanoscale structural inhomogenities at a view of fluctuations of thickness and densities of films. Values of contrast between more dense and less the dense sites reaches 10 %, the sizes more the dense grains make 20-50 nm, and less the dense channels: 5-15 nm. The value of a degree of nanoinhomogenity is promoted by growth of the content of a selenium in a composition of films, and also rise in temperature of a substrate and velocity of condensation at their deposition. For substances from compositions, by the close up to germanium, in optimum technological modes of vacuum condensation are shaped nanohomogenity amorphous films without essential fluctuations of density on gauges more than 1 nm.

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R.R. Romanyuk1, O.G. Mykolaychuk2

Optical Absorption Edge of i-Containing Amorphous GeS-Films Before and After Influence of Electron Beam

1Western Scientific Centre, 4, Mateyko Str., Lviv, 79000, Ukraine, -mail: zncnan@mai.lviv.ua
2Ivan Franko L'viv National University, 8, Kyryl and Mephodiy Str., Lviv, 79005, Ukraine

On the basis of absorption and reflection spectra of amorphous films, received by discrete evaporation, absorption factor is calculated and width of an optical gap of films (GeS)1-xBix (x = 0; 0,03; 0,07; 0,11; 0,15) before and after influence of electronic beam is determined. ³-additives shifts absorption edge to low-energy photons region, increase absorption factor, and decrease optical pseudogap 0 width. Electrons' influence causes shift of absorption edge of samples to high-energy region by 0,06-0,08 eV and increases 0. Research results fall into the model of a heterogeneous structure of condensates.
Key words: chalcogenide films, GeS, optical absorption edge.

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V.M. Gunko1, I.F. Myronyuk2, V.L. Chelyadyn2, R.V. Ilnytsky2, V.. Kotsyubynsky2, T.V. Gergel2, R. Leboda3,
J. Skubiszewska-Zieba3

Structural and Adsorption Properties of Fumed Oxides TiO2, TiO2/SiO2 and TiO2/Al2O3

1 Chuiko Institute of Surface Chemistry NASU, 17 General Naumov vul., Kiev, e-mail:gun@voliacable.com
2Precarpathion National University named after V. Stefanyk, 57 Shevchenko Vul., Ivano-Frankivsk, e-mail:myrif@rambler.ru
3 Maria Curie-Sklodowska University, Lublin, e-mail: leboda@hermes.umcs.lublin.pl

There were synthesized the fumed oxides of metals on the basis of titania: ҳ2/SiO2, ҳ2/Al2O3 and ҳ2/SiO2/Al2O3 with little content of SiO2 and Al2O3 . There were studied the morphology and structure of particles of these materials by means of the methods of X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FTIR) and low temperature adsorption of nitrogen and argon. It is shown that titania includes phases of anatase and rutile are composite oxide materials, but their relative content changes depending on the ratio of the precursors and reaction conditions. Nanodispersed materials are characterized by the insignificant aggregation degree of primary particles.
Key words: fumed titania, fumed ҳ2/SiO2 , fumed ҳ2/Al2O3 , fumed ҳ2/SiO2/Al2O3 , anatase, rutile, XRD, FTIR, adsorption, morphology of particles.

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Ye.V. Timukhin, V.F. Zinchenko, E.O. Zhikhareva, I.P. Kovalevska

Effect of EuF3 Admixture on the Phase Composition and Optical Properties of Lead Fluoride

A. V. Bogatsky Physico-Chemical Institute of NAS of Ukraine, 86 Lustdorfska Doroga Str., 65080, des,
Ukraine, vfzinchenko@ukr.net

Interaction of Lead Fluoride with Europium () Fluoride admixture was studied by the methods of X-ray phase analysis, thermal analysis and diffuses reflectance spectroscopy. The character of exchange reactions between Oxygen-containing admixture to the initial specimen of PbF2 and EuF3 with the partial neutralization of the first one has been established. The alternative behaviour of the doped and non-doped materials in the solid state and in the post-melted state was shown.

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L.D. Yurchyshyn

Crystal Chemistry Analysis of Defective Subsystem Non-Stehiometry of Germanium Teluridu

Physical-Chemical Institute at the Vasiliy Stefanyk Precarpathian National University, 201,
Galytska Str., Ivano-Frankivsk, 76000, Ukraine, E-mail:freik@pu.if.ua

Crystal chemistry formulas for non-stehiometry p-GeTe with surplus of Teluru on condition of formation two- and four charging vacancies of Germanium are offered. Defective subsystem is analysed at selfalloying Germanium. On the basis of comparison results calculation of dependence concentration of charge current from the size of deviation from stochiometric composition with an experiment is done a conclusion about the dominant defects of points.

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I.S. Petrik1, .P. Linnik1, N.P. Smirnova1, A.M. Eremenko1, G.Y. Kolbasov2, V.S. Vorobetz2

Photoelectrochemical and Photocatalytic Properties of Nanosized ҳ2 and Fe3+/TiO2 Films

1Institute of Surface Chemistry, Ukrainian National Academy of Sciences, 17 Gen. Naumov str., Kyiv 03164, Ukraine, E-mail:smirnat@ i.com.ua
2Institute of General & Inorganic Chemistry, Ukrainian National Academy of Sciences, 32/34 Palladin str., Kyiv, 03680, Ukraine E-mail:kolbasov@ionc.kar.net.

The nanosized films ҳ2 and Fe2Ti2O7 (Fe/Ti) on the glass substrats were fabricated by sol-gel technique. The structure and optical properties of these films were characterized using TEM, ellipsometry, XRD and UV/Vis spectroscopy. Resistivity and and the position of flatband potentials were estimated by photoelectrochemical measurements. The optical spectra and quantum yeld measurements give evidence about sencibilization of ҳ2/Fe2O3 films to the visible spectral range.

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H.Ya. Babushchak1, N.V. Stashko1, N.D. Freik2

Crystal Chemistry of Points Defects in n-ZnS and Mechanism of Cooperation with Oxygen

1Physical-Chemical Institute at the Vasiliy Stefanyk Precarpathian National University, 201, Galytska Str., Ivano-Frankivsk, 76000, Ukraine, E-mail:freik@pu.if.ua
2Ivano-Frankivsk gymnasium state 1, 1, Kaluske shose Str, Ivano-Frankivsk, 76008, Ukraine

The crystal quasi chemistry formulas as for n-ZnS with own of point defects, and doping isovalent impurity oxygen are offered. Dependence of concentration of defects, free carriers of a charge and Holl concentration from a degree non-stehiometry and contents of the doping impurity is calculated. Influence of a deviation from stehiometry, shares of Zinc in own units, sizes disproportion internodal Zinc on conditions of realization of n-p-transitions is investigated.

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S.Ya. Pukas, R.E. Gladyshevskii

Novel Compound with Er3Ge4 Crystal Structure in the Gd-Ge System

Ivan Franko National University of Lviv, Kyryla i Mefodiya St., 6, UA-79005 Lviv, Ukraine e-mail:s_pukas@franko.lviv.ua

A new binary compound Gd3Ge4 was synthesized. It was established by X-ray powder diffraction that it crystallizes with the orthorhombic Er3Ge4 structure type (space group Cmcm, a = 4.0968(6), b = 10.745(2), c = 14.352(2) Å). The isostructural compounds were early observed in the {Tb, Dy, Ho, Er, Tm, Lu}-Ge systems. For the compound Tb3Ge4 the cell parameters were determined at 1170 K: a = 4.0633(5), b = 10.675(1), c = 14.266(2) Å.

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O.O. Sapyanenko1, P.P. Gorbyk1,M.V. Tsebrenko2, L.S. Dzubenko1

The Influence Of High-Dispersed Silica On Phase Transitions In Polypropylene-Copolyamide Systems

1Institute of Surface Chemistry of NAS of Ukraine, 17, General Naumov Str., 03164, Kyiv, Ukraine
2Kyiv National University f/or Technology And Design, 2, Nemyrovych-Danchenko Str., 01011, Kyiv, Ukraine

One studied, with use both optical microscopy and differential thermal analysis techniques, that influence of pyrogenic silica with specific surface of 308 m2/g on structure-forming processes and phase transitions in PP/PA (polypropylene/co-polyamide) polymer blends exists at PP/PA equation of 30:70.

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L.Yu. Ostrovskaya

Capillary Properties of Microstructured and Nanostructured Carbon Films

V.Bakul Institute for Superhard Materials, NAS of Ukraine (Kyiv)

The possibilities to change wetting carbon films by structuring the film surface at micro- and nanolevels are discussed. It has been found that the structuring at the microlevel does not result in an increase of a contact angle and is restricted by the surface geometry (the inclination of surface structural elements to horizon). The wetting occurs by Wenzel-Deryagins mechanism for rough surfaces. Capillary properties of monocrystalline diamond (MD) and graphite (MD) change considerably if these materials are produced in the nanostructured form, namely, as nanocrystalline diamond (ND) and nanowalled graphite (NG). Water contact angles are, respectively 36 ± 2 for MD and 72±2 for ND. For hydrogenated surfaces, water contact angles are, respectively, 92 ± 2 and 106 ±3, which is comparable with polymers, e.g., Teflon. Tin contact angle for ND increases from 130 ± 2( (MD) to 158 ± 3. NG films exhibit very high hydrofobicity with a wetting angle of 144 ± 3, which is 1,8 times higher than that for MG. The anisotropy of the surface morphology caused by the nanostructuring impairs the wettability because of a change in the liquid phase geometry and the discontinuity in a three-phase contact line, which brings about a radically other mechanism of wetting nanostructures. It is shown that the surface of a nanostructured material should be considered as a heterophase, nanoporous one with the hierarchical organization of pores, which ensures a local suspension of the liquid above a nanopore and thus, non-wetting of the solid phase. In this case the liquid behavior is described by the Cassi-Baxter equipment for heterophase surfaces. This explains the extreme inertness of ND and NG to metals with van der Waals interaction, organic and inorganic liquids.
Key words: Carbon films, Wettability, Surface energy, Models of wetting, Micro- and nanostructuring, Surface morphology.

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V.M. Boychuk, O.V. Tkachyk, L.V. Turovska, N.I. Dykun

Crystal-Quasichemical Formulas of Not Stoichiometrical Lead Telluride with the Difficult Spectrum of Point Defects and Processes of a Self-Doping

Physical-technical faculty of the Vasiliy Stefanyk Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76025, Ukraine, e-mail:freik@pu.if.ua

Crystal-quasichemical formulas for crystals of n-and p-PbTe with the difficult spectrum of point defects in a cationic sublattice are proposed. Mechanisms of a self-doping of n-PbTe by Tellurium and of p-PbTe by Lead are analysed and requirements of embodying of n-p and p-n-transitions accordingly are determined.

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H.O. Sirenko, .. Fedoryshyn

The Gas Distinguished from the Carbon Fibers was Pyrocarbon-Plated

Vasyl Stefanyk Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine

The research by mass-spectrum method of the influence of pyrocarbon-plated on the gas distinguished from surface of the graphitized carbon fiber. It is shown how a tread of fibers influences on intensity of the characteristic points. It is adducing the mass-spectrums of the carbon fibers in the range of temperature 393-673 K.

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V.V. Prokopiv1, P.M. Fochuk2, I.V. Gorichok1, E.V. Vergak1

Description of Processes of Defects Creation in Undoped Crystals Cadmium Teluride by the Method of Thermodynamics Potentials

1Precarpathion National University named after V. Stefanyk, Shevchenko Str.,57, Ivano-Frankivsk, 76000, Ukraine, e-mail:prk@pu.if.ua
2Institute of Inorganic Chemistry, Chernivtsi University, Kotziubinskoho Str., 2, Chernivtsi, 274012, Ukraine

The method of thermodynamics potentials expects concentrations of point defects and free transmitters of charge in the CdTe crystals depending on the technological factors of two-temperature to annealing (temperature of the annealing, partial pressure of pair of the PCd cadmium). It is set that in material of n-type the internodal atom of cadmium is a dominant defect and in material of p-type is vacancy of cadmium. It is also shown that for all explored region of T and PCd concentration of the charged defects are anymore than concentrations of neutral.

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A. Shalygin, A. Kalinkov, V. Tishenko

Model Researching of Physic-Chemical Processes Being in the Defects of the Protective Vacuum-Condensated Films

Odessa national academy of food technology, Kanatnaya st. 112, Odessa, 65039, ph. (0482) 29-11-31

The model of local processes propagating in pores of chromium and copper coatings deposed on steel 3 surface, has been proposed. Potentials of local corrosion centers being on surface of several thickness films were measured by probe. Currents of corrosion processes propagating in pores have been calculated. Weight losses and their rates were calculated. These meanings and gravimetric results were compared. The comparison of protective properties of these coatings has been did.
Key words: protective vacuum-condensated film, researching of local corrosion processes, model of distribution of current being in thin capillary.

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R.G. Cherkez

Peculiarities of FGM for Permeable Generator Thermoelements

Chernivtsi National University, Chernivtsi, Ukraine

Results of theoretical research on the use of inhomogeneous materials (FGM) for permeable thermoelements are represented. Methods of their computer design aimed at achieving maximum power conversion efficiency are described. For ³- based materials optimal distributions of permeable thermoelement inhomogeneity in the form of dependences of thermoelectric coefficient, electric conductivity and thermal conductivity along the leg height are given for the case when heat carrier input temperature is 600, and temperature of thermoelement cold junctions is 300. It is shown that the use of FGM in permeable thermoelements allows a factor of 1.3-1.6 efficiency increase for Bi-Te materials as compared to classical thermoelements of bulk materials.

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.O. Sirenko, L.V. Bazyuk

Influence of Parameters of Graphites on Wearproofity for mposite Materials on the Base of the Aromatic Polyamide

Vasyl Stefanyk Precarpathian National University, 57, Shevchenko Str., Ivano-Frankivsk, 76000, Ukraine

Dependence between wearproofity and parameters of distribution of graphite for composite materials based on aromatic polyamide s explored.

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P.I. Melnyk, I.Ya. Petryk, V.M. Kramar, I.Yo. Perkatuk

Approximate Evaluation of Correlation Between Solid State Transformation Energy and Process Latent Heat in Metals

Precarpathion National University named after V. Stefanyk, Shevchenko Str.,57, Ivano-Frankivsk, 76000,
Ukraine, e-mail:ivan.petryk@rambler.ru, phone: +(03422) 59-60-80

The posibility of solid state transformations energy evaluation in metals through process latent heat registration with using characteristic frequencies of crystal cell atomss vibration are studied.

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.. Stelmakh, L.Yu. Matzui, L.L. Vovchenko

Electrical Resistivity of Composite Materials Based on Thermoexfoliated Graphite

Physics department, Kyiv National Taras Shevchenko University, Glushkov av. 2, Kyiv, Ukraine, 03680, E-mail:LegoStar@univ.kiev.ua

The influence of type of thermoexfoliated graphite (TEG(1), TEG(2)) and concentration of polymer on electrical properties of composite materials (CMs) graphite polymer and temperature dependence of electrical resistivity for this CMs have been studied. It was experimentally found, that increase of TEG content in CM leads to decrease of electrical resistivity. By using the experimentally defined critical concentration of TEG (c the critical index t have been determined for CMs TEG epoxy resin and TEG polyvinylacetate.
Key words: thermoexfoliated graphite, organic compound (binder), electrical resistivity, composite materials.

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O.Ye. Turetsky, G.G. Chemeresyuk, O.O. Chernova

Technological Aspects of Cadmium Sulphide Films Production by Electrospray Pyrolysis

Odessa National Mechnikov University, 2, Dvoryanska Str., Odessa, 65026

Some technological aspects of obtaining semiconductor photosensitive cadmium sulphide films by means of electrospraying a solution that contains sulphur and cadmium ions in a certain concentration onto the heated substrate are considered. It is shown that the essential difference in the character of dispersion of water and alcohol solutions of salts is due to the difference in their physical and chemical properties such as the electric conduction and the surface tension coefficient. Both to improve the dynamic characteristics of aerosol formation and to form the structure-sensitive parameters of samples, it is optimum to use the alcohol solution of salts in the film production technology that makes use of electrically charged aerosol. The influence of different temperatures of the substrate on the formation of the film surface microrelief is investigated. The relation is established between the temperature of CdS films growth and their electric and photosensitive characteristics. The results of the study make it possible to recommend ways of optimization of the production conditions for not only cadmium sulphide films but also for those of some other semiconductor compounds.

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B.Ya. Venhryn1, I.I. Grygorchak1, Yu.O. Kulyk2, S.I. Mudry2, R.Ya. Shvets1

The Study of the Porous Structure of the Carbon Materials by the Small Angle X-Ray Scattering Method

1 Lviv Politechnik National University 1 Kotliarevskyi Str., Lviv, 79013, Ukraine
2 Ivan Franko Lviv National University 8 Kyrylo and Mefodiy Str., Lviv, 79005, Ukraine

The porous structure of the nanoporous carbon materials received by the activated carbonization of styrene-dyvinilbenzene copolymer (SBC) and fruit stones (FS) is studied by the small angle x-ray scattering method. On the base of the Guinier approach the distribution functions of nanoporous f(Rg) are calculated according to the electrons radius of the inertion Rg and the average sizes of nanoporous are defined. The method of the specific porous area of nanoporous carbon is proposed and the comparative analyse of the porous structure of the studied materials is done.
Key words: nanoporous carbon, porous structure, specific area, small angle x-ray scattering.

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E.Ph. Shtapenko

Of Derivation of a Continuous Number of Hard Solutions in Transition Bed «Substrate "- Film" Surveyed at an Electrocrystallization

Dniepropetrovsk National University of Railway Transport named after Acad. Lazaryana 2 Acad. Lazaryana St, 49010, Dnipropetrovsk, Ukraine

In paper the mechanism of derivation of a continuous number of hard solutions in transition bed «substrate "- film" surveyed at an electrocrystallization. Within the framework of the theory of elasticity is obtained expressions for calculation of operation necessary for implantation of an adatom in a crystal lattice of a substrate.

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