No Abstract.

In the paper, we report development of two reflectometers in IPM RAS. One enables investigation of the angular and spectral characteristics of mirrors with any shape of a reflecting surface in the 0.6-20 nm spectral range. The other, designed especially to study the influence of EUV sources on the reflecting characteristics of the mirrors, allows testing of flat samples. Owing to a high aperture ratio (solid angle of 0.034 steradian), high reflection coefficient of mirrors, powerful windowless X-ray tube, and effective detector, the reflectometer provides a resolution of the reflection coefficient variation at a level of 0.1%.

The paper describes the main features of the pulsed low-pressure gas discharge in oxygen and xenon, which burns in typical conditions of EUV source operation. It is shown that in a mode of the superdense glow discharge the electron temperature in the discharge plasma is high enough to provide for generation of EUV radiation without magnetic compression of the plasma column.

Lithography simulation has become an indispensable tool for understanding and optimization of lithographic processes and for the development of new processes. Aerial image simulations are used to evaluate the imaging of designed photomasks by projection steppers or scanners and to explore the impact of optical parameters such as numerical aperture, spatial coherence, defocus, and wave aberrations on the imaging performance. Other simulation approaches are used to describe the impact of the photoresist thickness, of the post exposure (PEB) temperature, and of the development characteristics of the photoresist on the total process performance. This article reviews the most important modeling approaches which are used in lithography simulation. Several examples demonstrate the application of modern simulation tools for the optimization of lithographic mask and illumination geometries. This includes the application of genetic algorithms for global parameter optimization and the rigorous electromagnetic modeling of light diffraction from advanced lithographic masks.

The formation of contact holes in semiconductor integrated circuit device fabrication is considered. The contact holes size usually corresponds to the resolution of the stepper. The vortex mask technique is intended to improve resolution in patterning contact holes through exposure. By adopting this technique, an isolated contact hole with a diameter of approximately 80 nm and 250 nm pitch can be formed with KrF, NA=0.63. The conventional vortex mask approach permits the single exposure printing of regular arrays of contact holes. The unwanted contact holes should be erased from resist pattern by exposing the wafer with a second, conventional trim mask. The double exposure process makes the fabrication more expensive. In the present work the vortex mask for single exposure printing of irregular arrays of contact holes is suggested.

A pupil filter optimization algorithm is presented. The algorithm was tested for low-aperture stepper. The experimental data for resolution and depth of focus enhancement are described.

A new way of creation of the stable and constantly reproduced at various experiments surface microwave discharge near a flat dielectric antenna was developed and experimentally investigated at a wide range of air pressure p=10^-3 ÷10³ torr. The breakdown characteristics determining a threshold of a surface microwave discharge appearance were studied. Longitudinal size and velocity of spreading of a surface microwave discharge in air were determined at a wide range of gas pressure, microwave power and pulse duration. The spatial-temporary evolution of electron density, gas and vibrational temperatures were investigated. It is shown that the surface microwave discharge can be used as a plasma source for microelectronics and material processing.

A comparison of ICP and microwave plasma sources was carried out under the same discharge conditions, in the same discharge chamber and using the same diagnostics method. Investigations were fulfilled in a wide range of external discharge parameters (at pressures 0.5 - 20 mTorr and for powers deposited in the plasma 400 - 1500 W) in boron trifluoride and in argon discharges. A variety of plasma parameters (T_e, n_e, n₊, EEDF) and their radial profiles at a 2 cm distance above a wafer holder were determined by using single Langmuir probe technique. Analysis of measurements has shown that the charged particles concentrations in ICP plasma are higher than are obtainable in microwave discharge, for deposited power 1.2kW the ICP source produced ion number density ~10¹² cm^-3. The required plasma uniformity can be maintained in ICP plasma over a more wide range of external discharge parameters then in microwave plasma. The use of microwave plasma source gives a bi-Maxwellian type EEDF, whereas the EEDF of ICP plasma is close to the single Maxwellian distribution with electron temperature higher then the temperature of cold electrons in microwave discharge. BF₃ plasma is electronegative, with a degree of electronegativity ~0.3-0.5 for both plasma sources.

Plasma parameters and chemical kinetics of Cl₂/Ar plasma were investigated aimed at understanding the mechanism of Ar addition on mass composition of charged and neutral particles. The analysis was based on both experimental methods and plasma modeling. It was found that addition of Ar to Cl₂ leads to deformation of the electron energy distribution function and to increase of the electron mean energy. Direct electron impact dissociation of Cl₂ molecules represents the main source of chlorine atoms in plasma volume. The contributions of stepwise dissociation and ionization involving Ar metastable atoms were found to be negligible. Addition of Ar to Cl₂ causes the decrease of both electron and ion densities due to the decrease of the total ionization rate and the acceleration of heterogeneous decay of charged particles.

In this work, we investigated both etching characteristics and mechanisms of Au thin films using Cl₂/Ar gas mixture in an inductively coupled plasma (ICP) system. For these purposes, a combination of experimental methods and modeling was used. It was found that an increase in Ar mixing ratio under constant operating conditions causes non-monotonic behavior of Au etch rate, which reaches a maximum 80% Ar. A study of surface composition using X-ray photoelectron spectroscopy (XPS) showed that the etching in chlorine-rich plasma is escorted by accumulation of AuCl_x on the etched surfaces. Langmuir probe measurements indicated a noticeable sensitivity of both electron temperature and electron density to the change of Ar mixing ratio while 0-dimensional model of volume kinetics showed monotonic change of both densities and fluxes of active species such as chlorine atoms and positive ions. However, analyses of surface kinetics showed that the non-monotonic etch rate behavior may be produced by the concurrence of physical and chemical pathways in ion-assisted chemical reaction.

Lateral distribution of particles density in the plasma across the wafer surface is critical for plasma processing steps in IC manufacturing and should be optimized at the stage of process design. Optical emission tomography of the plasma is promising technique for this goal. Presented investigation is carried out to develop the algorithms of tomographic reconstruction of 2D-distribution plasma species density from its characteristic optical emission data. The geometry of the tomographic data acquisition was chosen to be compatible with the commercial types of plasma reactors. Advanced accuracy of reconstruction has been achieved by including the classes of the space profiles of inhomogeneities based on the discharge physics into reconstruction algorithm. The tests have been performed with the kinds of inhomogeneities, which is most probable in plasma reactors with HDP sources.

Residual resist removal availability from surface of semiconductor structures Si and GaAs by directed hydrogen atomic flow has been shown. The influence of treatment time and temperature on surface cleaning efficiency was studied. It has been shown that cleaning by atomic hydrogen flow leads to surface of GaAs roughness reduction. Comparative studies of residual photoresist removal efficiency by oxygen plasma, ozone and atomic hydrogen have been carried out. Organic contaminants removal efficiency by atomic hydrogen is comparable to the efficiency of traditionally used cleaning method by oxygen plasma. The merits of treatment by AH flow are compatibility of the process with technology of low-k dielectrics, absence of surface oxidation of semiconductor materials, and minimization of energy and charged particles effect on semiconductor structure.

Successful removal of fluorocarbon residues on silicon structure using neutral atomic hydrogen direct flow is reported. It has been stated that the treatment of samples in atomic hydrogen direct flow of density of 2x10¹⁵ at. cm^-2 s^-1 leads to decreasing of fluorocarbon residues concentration on the surface of structure by 5 orders of magnitude. The concentration of fluorocarbon residues after AH treatment is at the hum level characteristic for the absolutely clean surface exposed in atmosphere air. Removal fluorocarbon residues is being realized at temperature of 20-100 ° both from the planar surface of a structure and from the sidewalls and bottom of the contact holes with diameter of 0.3-0.25 μm and depth of 1.2-1 μm. The time of treatment as 2 min is quite sufficient for fluorocarbon residues removal.

Cobalt silicide layers were formed in Si and Si_1-xGe_x/Si heterostructures by using ion beam synthesis (IBS) at specified regimes and conditions. Effect of the type of the initial target and its temperature during implantation on the phase composition and structure of synthesized layers were investigated. The nonmonotonic dependence of the sheet resistance of synthesized films on ion current density was detected. Thin CoSi₂ films on Si_0.6Ge_0.4 structures with the sheet resistance of 17 Ohm/ were obtained using IBS with subsequent rapid thermal annealing.

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

Investigations of the Ti-Co, Ti-Ni and Ta-Ni thin films produced by magnetron co-sputtering and electron beam co-evaporation on Si substrates heated to 700-800° in nitrogen ambient with and without buffer layers are described. The TEM data show clear phase separation of TaN and NiSi₂ for the Ta-Ni film deposited in a high N₂ pressure ambient. Deposition at lower N₂ pressure led to the formation of a mixed Ni-Ta-Si layer. The phase separation effect was absent for Ni-Ti films at high N₂ pressure. The presence of buffer layers strongly affected the surface diffusion reactions in the Co-Ti-Si system. Formation of Ti-(O) or CoSi_x amorphous layers at the Si surface prevented the interdiffusion of Si and Co, such that even pure Co or Co₂Si layers could be formed.

The limitations attributed to SIMOX material synthesized with using of an ion implantation of oxygen are surveyed. A new theoretical approach on the base of the phase transitions theory of Ginsburg - Landau is advanced. It is shown that a basic improving of any variants of SIMOX process cannot be achieved by virtue of the fundamental physical reasons. A method of the ion synthesis of buried layers of silica-based glasses is offered. The results of simulation of formation of the buried glass-contained layer in the silicon substrate are represented. The method allows one to maintain the basic advantages of SIMOX process and to overcome some serious limitations inherent to the latter. On the base of this method a new approach to creating of MOS transistor for SOI/MOS logic gates is offered.

We have applied spectroscopic ellipsometry with binary polarization modulation to study the refractive index n(λ) and extinction coefficient k(λ) spectra of as-deposited and irradiated with nitrogen ions polymethylmethacrylate (PMMA) and polystyrene (PS) films in 300-1030 nm range. The results of performed investigation confirmed the possibility and estimate restrictions of the ion implantation for local change the refractive index of polymeric materials.

No Abstract.

This work contains the results of the investigation of dissolution of SiO₂ after the implantation by Ar⁺ and C⁺ ions with the irradiation energy of several tens of keV. The measurements were carried out directly in the liquid in-situ with an atomic force microscope. The quantitative data about the distribution of the etching rate on the depth of the implanted layer were obtained. The change of the dissolution rate of SiO₂ after implantation is due to with the change of the internal structure of the material. The results of the quantum-mechanical calculations of the internal structure of SiO₂ before and after implantation are given.

The proposed lower methods of silicon surface formation using heat treatment in wet environment (including chemical surface assembling by the molecular deposition method) and the smart technique allow producing high-quality SOI-structures suitable for using in special ICs, semiconductor devices, micromechanical systems and sensors. The basic idea of the chemical surface assembling by the molecular deposition method that may be suitable for precision “synthesis of surface” of required composition and for surface modification consist in consecutive deposition of monolayers of structural units with given chemical composition.

The results of experiments on research of electroforming processes in open “sandwich”-structures Si-SiO₂-W (silicon - silicon dioxide - tungsten) with thickness of silicon dioxide about 20 nm are shown. The basic distinction for silicon of p- and n-types conductivity is marked: in the first case usual for electroforming N-type current-voltage characteristic and in the second S-type curve typical for electric breakdown with thermal instability are observed. The mechanisms of processes are discussed. The marked distinction is connected with the fact that in structures n-Si-SiO₂-W the current is transported basically by electrons which dissociative attachment to molecules on a surface of an insulating slit leads to their destruction and conductive phase particles formation from them. In a current through structures p-Si-SiO₂-W the electrons prevail only at initial moments of electroforming, in process of conductive medium accumulation their share falls by one - two orders, and the current is transported by holes, which cannot participate during formation of conductive phase particles.

Method of Reactive Ion Beam Synthesis of thin films was developed. The phenomenological model of synthesis is founded on consideration main components of ion beam plasma (IBP) in space of the ion beam transportation and phenomenon occurring on treatment surface under the action of ion beam is submitted. Processes of deposition metal and dielectric films from ion beam, neutralization of positive potential on a surface U_s of dielectric are considered. The value of surface potential is established, it is calculated a part of reflected low energy ions and influence of U_s on Langmuir gap is determined. The size of Langmuir gap d_L depends, according to equation of Child-Langmuir from density of an ion current on a substrate j and potential difference between plasma and substrate U. The theoretical calculations have showed that flow of ion beam and neutral particles on treatment surface are close on order of the value. Division of an ion and neutral component of ion beam plasma in a magnetic field and the subsequent independent deposition of a thin film from the divided ion and neutral streams has shown that growing of the film is conditioned by introduction accelerated ion in subsurface layer of the film or substrate.

To develop reliable intercomponent insulation methods to fabricate devices and IC's based on GaAs multiplayer heterostructures the formation of high-resistivity regions in these structures by selective F⁺ and B⁺ ion implantation is studied. The implantation and the consequent annealing regimes are established.

Macroporous silicon is a material which widely extends the traditional application areas of silicon from modern microelectronics to optoelectronics, microphotonics, micromechanics, sensorics, etc. Macroporous silicon is a material produced from silicon (100) single crystal wafers. It is characterized by an array of straight pores penetrating from a top to a bottom of the wafer along, as a rule, <100> direction. The array of the ordered or randomly nucleated macropores is normally produced by means of electrochemical etching of the silicon wafer with preliminary formed inverse pyramides using lithographic technique or directly on a top of the untreated wafers, respectively. Parameters of the macropores produced (a pore size and a pore wall thickness) was found to depend in a high extent on the silicon doping level, e.g. the lower concentration of doping impurities the larger pore sizes can be obtained. It was shown as well that a randomly nucleated pore growth is a two-stage process comprising a pore nucleation stage and an in depth pore growth stage. The first stage is a critical one which determines a density of the pores finally produced. Two different models of the nucleation stage has been proposed and discussed in the present work. Taking into account the main conclusions of the models a new technique based on fine focused ion beam implantation has been developed to produce an array of the ordered macropores with submicron sizes.

Periodic structures of grooved Si with lattice constants A = 2 - 4 µm, having the horizontal modulation of the refractive index, n, and acting as the 1D Photonic Crystal (PC) in the middle and far IR range (5-50 µm), have been fabricated by means of wet anisotropic etching of (110) oriented single crystalline silicon. The “gap maps” for both the empty matrices of periodically grooved Si and the composites infiltrated with liquid crystal (LC) of the average refractive index n=1.6 have been calculated. These maps display the frequency regions of photonic band gaps (PBGs) as a function of the filling factor D_si/A and simplify the design of 1D PC structures for user-specified wavelength range. FTIR measurement revealed wide stop bands in the reflection and transmission spectra. Infiltration of the periodically grooved Si with the nematic liquid crystal E7 results in a shift of the main band gap to the higher wavelengths and in the consequent changes in the secondary stop bands. It is shown that polarized spectra of grooved Si infiltrated with LC allows determination the refractive index of the LC and the orientation of its molecules.

Raman and optical spectroscopy, conductivity and steady-state photoconductivity measurements, spectroscopic ellipsometry and atomic force microscopy (AFM) techniques were used to determine the properties of microcrystalline (μc-Si:H) and amorphous (a-Si:H) hydrogenated silicon films deposited at low temperatures by a conventional plasma-enhanced chemical vapour deposition (PECVD) reactors from silane-hydrogen mixtures. In order to gain insight into the mechanisms of transport and recombination in μc-Si:H films we study effect of isochronal annealing at 300-600° C on their properties.

The optical properties of polycrystalline silicon films with oxygen incorporation in grain boundary were experimentally studied. The Raman scattering photoluminescent and Fourier-transformed infrared spectra were measured. The morphology of the films were studied by atomic force microscopy. The strong correlation between the oxygen content and optical properties, and polarization was found. The oxygen diffuse incorporation corresponds the energetic levels in band gap around E_c-0.27 eV. The thermal annealing of polycrystalline film by the temperature more than 150° C produces the siloxane bonding with defect level in energy diagram near E_c-0.14 eV. The quantum beats of intensity of optical and electronic signal due to the quantum interference of closed electronic states was studied.

In the present paper the peculiarities of nucleation stage of deep anodic etching of silicon are studied. The dependence of the depth of etching crater obtained for silicon samples of p-type conduction with different resistivity upon the regimes of anodic etching processes has been determined. On the basis of the experimental results obtained the “bottleneck” effect observed both at the first and second stages of pore growth is explained.

A gradual transition from quasi-hexagonal to quasi-one dimensional pore distribution during deep anodic etching of a uniaxially stressed silicon plate was experimentally observed to increase with mechanical loading.

Demonstration of porous anodic alumina application for photonics and optoelectronics is presented. Investigation of photonic structures and nanocomposites based on porous anodic alumina is performed. Techniques of highly ordered porous structure formation are demonstrated. Features of nanocrystal template deposition into nanopores are discussed.

On the base of the transmission electron microscopy with super-high resolution (STEM) data the behavior of the Si lattice parameters in the surroundings of β-FeSi₂ precipitates formed by ion beam synthesis (IBS) method. Despite the fact that the spots observable on the STEM image obviously are not the images of lattice atoms, the measuring of the distances between them permits to get some information about the parameters of the Si lattice in the (110)Si cross-section. Namely, it appears that β-FeSi₂ precipitates formed by the way specified above are not subjected to any substantial tensions. The important changes of lattice parameters detected are connected with a number of the defects more local. Particularly, dislocations can act as such defects.

Two different ways of oriented carbon nanotube (CNT) selective growth are investigated. At first, template assisted vertical oriented CNT formation is used. We developed a process of individual (isolated) CNT growth in porous anodic alumina at position determined by nanoimprinting. Additionally a new fabrication method of planar nanoelements based on carbon nanotubes is described. The prototypes of nanoelements using an autoemission are designed and experimentally realized. Obtained electric field thresholds are less than 3V/μm.

This paper reports on the production technology, features and practical application of capabilities of glass-coated micro- and nanowires fabricated by casting from the liquid phase. Micro- and nanowires with diameters from 80 nanometers to 1 micron have been received using improved technology of microwire casting by Ulitovsky method. The authors offer a technology of thinning such wires, as well as new manufacturing techniques of the filiform composite nanostructures on their basis. Some physical properties of the received micro- and nanowires have been investigated.

A technology of smooth 15 - 50 nm thin Bi-film fabrication with the surface roughness of about 1 nm using two ultrahigh vacuum film growth methods, partially ionized beam deposition (PIBD) and molecular beam deposition (MBD), was developed. The dependence of film surface morphology on the key growth parameters, deposition rate, growth temperature, film thickness, and deposited particles energy was investigated by atomic force microscopy, and optimum growth conditions were determined. In the case of PIBD method, the accelerating voltage was found to influence the surface morphology most distinctly. The most uniform and smooth films with equal size grains and minimum roughness of 1 nm were grown at the accelerating voltage 3 - 4 kV. It was also found that bismuth films grown under the optimum condition 4 kV become continuous when the film thickness is more than 10 nm. In the case of MBD method, a decrease of the growth temperature down to 40°C substantially suppresses the growth of surface hillocks and the film surface roughness is reduced down to 1 nm. The obtained results can promote developing a nanotechnology for nanowire and quantum-well structure fabrication using thin semi-metallic Bi films.

This work is dedicated to experimental studies of the action of fraktal-matrix strukturizator “Aires” on the processes of increasing on the thin nano-dimensional films of copper, titanium and number of others. It is established that under the action of strukturizators it is possible to obtain films with the clearly expressed fraktal structure, moreover at different levels. Are given the results of a study with the aid of optics, SEM and AFM of the microscopy. As a result of a complex of the lead researches influence fractal-matrix strukturizators on the processes proceeding at condensation thin nano-dimensional films from vapor or the plasma environment with use of methods magnetron ionic - plasma spattering and thermal vacuum evaporation is revealed.

Scanning tunneling microscopy (STM) and reflection high-energy electron diffraction (RHEED) experiments were performed to study growth modes induced by hyperthermal Ge⁺ ion action during molecular beam epitaxy (MBE) of Ge on Si(100). The continuous and pulsed ion beams were used. These studies have shown that ion-beam action during heteroepitaxy leads to decrease in critical film thickness for transition from two-dimensional (2D) to three-dimensional (3D) growth modes, enhancement of 3D island density and narrowing of island size distribution, as compared with conventional MBE experiments. Moreover, it was found that ion beam assists the transition from hut to dome shaped Ge islands on Si(100).

As is shown, threshold voltage on the Au film that is necessary for electric contact depends on starting pressing force of the probe and interstatic interaction. Natural oxide on the Al surface can be a reason for amplification of threshold voltage. Under the action of pressing force oxide paths expand and oxide can be punctured.

Iron based nanocomposites are of great interest in particular because of their magnetic properties. Preliminary results on image deposition from iron dodecacarbonyl by focused electron beam are presented. The specific electric resistance of fabricated lines was measured in the range from 4•10^-2to 10³ Ω cm dependently on deposition conditions. It was observed, that if the beam current increases, specific resistance sharply decreases. Positive temperature coefficient of conductivity for such material was determined. Effective activation energy of conductivity changed from 3-5kJ/mol for high conductivity lines to 15-25kJ/mol for low conductivity lines. Obtained data are considered on the base of representations of produced lines material as nanoclusters of iron spread in amorphous carbon matrix. The resistance change of deposited lines in media of different vapours and gases was estimated.

Recent developments of terahertz wave generation devices utilizing lattice and molecular vibration are introduced. They are semiconductor Raman laser and amplifier, parametric generation of terahertz wave using phonon-polaritons in semiconductors and dielectrics, together with electronic devices: TUNNETT diode and ISIT. Future important applications will be in the field of medicine, biology, and pharmacy.

Advances in microwave electronics result in development of more and more sophisticated devices. For all complicated microwave systems it is necessary to have the switch of the signals. It refers to the transceivers, the multi-channel systems, the control systems and many other civil and military applications. In this article the development of the 10 GHz 1:2 switch for use in the communication and radar systems is reported. Switch is designed for realization as MMIC on GaAs heterostructure substrates. It incorporates a hybrid design with directional couplers. As variable impedance elements, the field effect transistors, connected to the directional coupler arms in parallel to the channel, are used. Tuning and optimization of the circuit was performed using Microwave Office software by Applied Wave Research, Inc.

Some problems arisen from the fabrication of the nano-scale transistors are discussed: modification of the silicon-on-insulator (SOI) under (a) thinning procedure (multiplied oxidation), (b) structuring of the silicon nanolayers. Two types of SOI field effect transistors (FETs) were realized: in-plane-gate FET (IPGFET) with 40 nm minimum channel size and multi-channel top-gate FET on silicon on-insulator. The multi-channel 3D-gate FET fabricated on the uniform doped silicon layers are found to be the most advantageous variant of design.

We investigated the gamma radiation tolerance of a 0.5 μm SOI technology on Dele-Cut material. The radiation response was characterized by threshold-voltage shift of the front-gate and back-gate transistors. Results are compared with the radiation response of SOI MOSFETs on Unibond and SIMOX materials. Negligible degradation of subthreshold swing of back-gate n- and p-channel MOSFETs was observed, indicating that the primary effect of radiation is the introduction of charge in the buried oxide. The charge accumulation in the buried oxide was compared with MOSFETs fabricated in different SOI wafers. Buried oxide of Dele-Cut MOSFETs demonstrates the more pronounce γ-radiation tolerance in comparison with Unibond and SIMOX MOSFETs.

This paper presents a two-dimensional numerical analysis of planar power n-channel MOSFET structure with Schottky-barrier drain contact. A comparison in I-V characteristics between the Lateral Power MOSFET with Schottky-barrier drain contact and the conventional Lateral Power MOSFET with ohmic drain contact structures is given. The thyristor like I-V characteristics of the Lateral Power MOSFET with Schottky-barrier drain contact are found to be dependent of substrate contact location and neighboring cells interaction.

Possibilities of gallium arsenide technology in Georgia to fabricate microelectronic devices are described. Characteristics of technological processes and parameters of active and passive components for digital and analog IC's are given. A concept of technology implementation with allowance for design, epistructure growth and processing is proposed which is the basis of a foundry service for application-specific microelectronic components.

Molecular-beam - grown epitaxy heterostructure field-effect transistors employing a delta-doped channel have been fabricated and investigated. The results of studies of DC parameters of δ-FET's of different configuration can be regarded as the best obtained by other authors for single δ-doped structures. These data as well as the results of modeling and simulation allow one to recommend the studied δ-FET's for digital and analog applications.

Using the methods of numerical device-and-process simulation we investigated the current distribution and the relative and absolute current sensitivity of the lateral bipolar dual-collector magnetotransistor (BMT) made in the diffusion well and with the substrate and well contacts connected. The analysis of the current flow at low injection level revealed the negative sensitivity mechanism. The negative relative current sensitivity appears in BMT as a result of the involved in recombination electron and hole flows redistribution induced by magnetic field, i.e., as the result of concentration-recombination mechanism of magnetosensitivity. The optimization of structure of BMT allows to increase the maximal meaning of relative current sensitivity approximately three times.

Electron-phonon interaction in two-dimensional (2D) heterostructures is discussed. The Boltzmann kinetic equation and mobility in 2D heterostructures, engineering of electron-phonon scattering in quantum wells, coupled quantum well and photovoltaic effect, decrease of channel conductivity with increasing sheet electron concentration in modulation-doped heterostructures are considered.

Effects of spatial inhomogeneity for the probability current density j_x (x, z) (or a quantum-mechanical current density ej_x (x, z) e is the electron charge) in the semiconductor 1D nanostructures in the form of joints in the direction of propagation of the electron wave (the x-axis) of narrow and wide (on the z-axis) rectangular quantum wires (QWs) (z-axis is the axis of the quantization) have been theoretically studied. The inhomogeneous distribution of the j_x (x, z) arises because of the interference of electron waves spreading in the wide QW simultaneously in different electron subbands. Special attention is given to effects of spatial reproduction and multiplication for electron waves in such nanostructures. It is shown that transverse distribution j_x (0, z) existing at the entry of the wide QW is reproduced with some accuracy at a definite distance X₁ from the joint and splits in symmetric (along the z-axis) 1D nanostructures into p identical profiles of the intensity lower by p times at the distance X₁/p. This picture is reproduced periodically in cross-sections X_q = qX₁ (q and p are integers). The results of numerical calculations of these effects in symmetric structures and their modification in asymmetric (on the z-axis) nanostructures are given.

We report on temperature scaling experiments on the integer quantum Hall effect plateau-to-plateau transitions as well as on the i = 1 plateau-to-insulating phase transitions in two-dimensional electron gas in In_0.53Ga_0.47As/InP modulation-doped heterostructures. We have measured the longitudinal ρ_xx and Hall ρ_xy resistivities as a function of magnetic field in the temperature range 40 mK - 4.2 K. It was found that for both types of transitions the scaling exponent has the same value κ ≈ 0.6-0.7. The scaling exponent obtained in our experiments is significantly greater than κ = 0.42, the value generally considered to be universal.

We investigate the interband tunneling processes in a new type of heterostructures (broken-gap heterostructures) made from InAs, AlSb, and GaSb. Both the single-barrier and double-barrier structures are considered with the lattice mismatched strain taken into account. It is found that strain and bulk anisotropy of quasiparticle dispersions can result in additional peaks of the tunneling probability. The current-voltage (I-V) characteristics show strong dependence on the lattice-mismatched strain.

We investigate theoretically the spin transport in array of Ge/Si quantum dots (QD). In frame of tight-binding approach we calculate the probability of hole spin flip for resonant tunneling through discrete energy levels in QD. Our studies are based on the calculation of overlap integrals between neighbouring quantum dots. For ground state the probability of tunneling with spin flip is two orders smaller than the probability of tunneling without spin flip. We find that the main source of spin flip is the structure-inversion asymmetry of Ge quantum dot. Every tunneling event is accompanied by the turning of spin on small angle and this provokes the spin flip. For excited states in QD, the probability of spin flip increases. We investigate the spin flip probability as dependent upon the size and the shape of a quantum dot.

The results of the investigation of the properties of a-SiGe:H/c-Si heterostructures fabricated by LF (55 kHz) PECVD are presented. Electrical model describing current-voltage characteristics of heterostructure in wide range of forward biases was developed. It was established that in a-SiGe:H/c-Si heterostructures the multitunnelling capture-emission mechanism prevails in low voltage range (U<1.0 V). At applied voltage higher than 1.5 V space charge limited current predominates. In the low reverse voltage range change of the transport mechanism was observed, which is connected with considerable decrease of band gap in amorphous alloy. In the high reverse voltage range ([U]>1.5 V) reverse current is controlled by the generation and recombination in depletion layer of a-SiGe:H.

The atomic structure, stability and electronic properties of various phases of zirconium and hafnium nitrides in both metallic MN and insulator M₃N₄ forms, and oxynitrides M₂N₂O (M = Zr, Hf) were studied using first-principles plane-wave DFT calculations. The orthorhombic Pnam structure of M₃N₄, which was experimentally observed for zirconium nitride, was found to be the most stable with regard to the rock-salt-type structure often offered for such compounds. The total energy calculations showed that the nitridation of zirconium and hafnium oxides is thermodynamically unfavorable, and the formation of nitrogen vacancies in M₃N₄ converts it into the metallic MN phase. Calculations of the electronic density of states showed that the rock-salt type structure of zirconium and hafnium nitrides leads to their metallic properties in both the MN and M₃N₄ phases, while the orthorhombic structure of the M₃N₄ phase reveals its insulating nature in agreement with the experimental observations. Calculations of the electronic structure of zirconium and hafnium oxynitrides with the cubic Bixbyite-type crystal structure found in a recent experimental study demonstrate that both Zr₂N₂O and Hf₂N₂O are insulators with large energy band gaps.

Based on the Hall-Shockley-Read formalism we have successfully demonstrated that of the surface generation of minority carriers (MC) in a semiconductor of the Si-MOS-structure, leaded in the strong in-equilibrium depletion state, is ineffective due to rapid establishment of the quasi-equilibrium between surface generation centers and MC band. At the silicon surface without deep levels MC can be appeared only due to the diffusion from the quasi-neutral region. However, this diffusion takes place only at T> 100°C. Thus, in the perfect Si-MOS-structure at room temperature the state of non-equilibrium depletion can be conserved the infinitely long time, as a MC thermodiffusion from a Si electroneutral volume at the T<100°C is ineffective. In this situation single source of the MC generation is the edge effect. This effect can be artificially enhanced by staggered inhomogeneity gate oxide. Then, in depletion layer under the (thick) oxide the quasi-equilibrium between surface generation centers and MC band will be not established due to continuous MC leakage in the more deep potential well under (thin) oxide. The MC leakage is continued until homogenezation of a semiconductor surface. Next, a MC generation velocity will be determined the edge effect only. Experimental time dependences of the generation current I_g(t) are found to be in accordance with these concepts. On dependences I_g(t) are observed two discrete current steps. The height of steps undepends from depletion voltage V_g and their durability increase with growth of V_g. The MC generation rate and surface recombination velocity were obtained by I_g(t) curves. Increasing of grading of a gate oxide thickness allow to rise a number of steps on the I_g(t) dependence. The edge effect in a MIS-structure easily is increased of external stresses that it is allowed to use the edge effect for the creation sensor-devices of a new type.

The metal single-electron arrays based on different materials using the developed models were analyzed. In the models the Poisson equation is solved numerically to determine the potential distribution in the structure. The current-voltage characteristics are calculated by master equation or Monte-Carlo method in dependence on voltages, geometrical and electrophysical parameters, background charges as well as the operating temperature. Good agreement with experimental data for the single-electron arrays based on different materials is achieved. The influence of the geometrical and electrophysical parameters on the drain-source current-voltage characteristics of the single-electron arrays including two or five islands has been studied. Computer programs, which are realized, have been included in the system NANODEV.

We investigated transfer resistance of single crystalline W (001) nanostructure in the temperature interval 4.2 - 295 K. It is found that the crossover from liquid - to gas-like flow electron transport takes place when electrode spacing is comparable to electron mean free path. Under diffusive electron transport both positive and negative signs of the transfer resistance are observed in the depending on the geometry of applied current. The latter is not found at ballistic electron transport. Transfer resistances change faster than liner dependence against the reversal electron mean free path.

The growth of an isolated island on the monocrystal surface with the structure incommensurable to that of the island is considered in the framework of the Zel'dovich-Volmer theory. The equation for the growth of a round island in the periodical field of the surface is obtained. The growth rate is proved to be oscillating in time, and the possibility for the growth to stop is shown.

First-principles calculations have been performed to determine the structures and relative energies of different zirconium chloride groups chemisorbed on the tetragonal ZrO₂(001) surface and to study the effects of the surface coverage with metal chloride groups and the degree of hydroxylation on the adsorption energies of metal precursors. It is shown that the molecular and dissociative adsorption energies of the ZrCl₄ precursor on the bare t-ZrO₂(001) surface are too small to hold ZrCl₄ molecules on the surface during an atomic layer deposition (ALD) cycle at temperatures higher than 300°C. On the contrary, it has been found that molecular adsorption on the fully hydroxylated zirconia surface leads to the formation of a stable adsorbed complex. This strong adsorption of ZrCl₄ molecules can lead to a decrease in the film growth rate of the ALD process at lower temperatures (<200°C). The energies of interaction between adsorbed ZrCl₄ groups at a 50% surface coverage has been found to be relatively small, which explains the maximum film growth rate observed in the ZrCl₄:H₂O ALD process. Moreover, we found that the adsorbed ZrCl₄ precursors after hydrolysis give rise to very stable hydroxyl groups, which can be responsible for film growth at high temperatures (up to 900°C).

The conductivity and Hall mobility have been measured in heterostructures with quantum well (QW) as functions of temperature and the QW width. If a tunnel-transparent barrier is inserted in the middle of a QW, the mobility increases in narrow wells and decreases in wide wells. The experimental data have been compared with the calculated dependences. It has been shown that the number of filled quantum well subbands depends on the well width and the presence of a barrier.

We investigate the subband dispersions in the InAs/GaSb quantum wells using Burt's envelope function theory and the scattering matrix method. The potential and carrier distributions as well as the level positions are derived by means of self-consistently solving the Schroedinger and the Poisson equations. The semimetal-semiconductor phase transitions have been obtained with the GaSb layer thickness decreasing and with increase of the bias voltage applied across the structure.

The effect of influence of different material parameters and structure design on IV-characteristic of RTD is considered in the paper. Special attention was paid to analysis of the interaction between classical and quantum-mechanical RTD regions. The combined numerical model of a resonant-tunneling diode, based on self-consistent solution of the Schroedinger and Poisson equations is presented. The interface charge was added to the Poisson equation and its approximation is also given. The simulation of IV-characteristics of RTD on In_0.53Ga_0.47As/AlAs and GaAs/AlAs was carried out by using the combined model and model modifications. As a confirmation of accuracy and adequacy of the proposed model there was achieved a good agreement between theoretical and experimental results. The effect of interface charge and sizes of the active regions on IV-characteristics of RTDs was also studied.

The quantum wave-guide strategy was applied to study the influence of surface scattering on quantum transport. It started from the time-dependent Schrödinger equation, then perturbation terms were obtained and the film conductance calculated via the kinetic equation. The sheet conductance of a thin metallic film, a spin-valve layered structure and a semiconductor quantum well were evaluated in different physical limits, in particular, for different roughness character, long wave roughness or ripples. The interplay between surface and bulk scattering was also considered. Various power laws for the conductance dependence upon film thickness were obtained. Qualitative agreement with available experimental data was achieved.

We report on physical mechanisms and methods for optical (λ=300-150 nm) patterning of thin alloyed layers of transition metals (Fe, Co) via laser-induced ferromagnetic ordering (LIFO) in the initially paramagnetic alloys. It is argued that LIFO preceded by film melting and arises due to phase separation in the alloys. Using a laser (λ=300-150 nm) interferometric technique for direct patterning on the phase transitions, we have successfully produced large-area (up to 1 cm) arrays of nanoscale (down to 100 nm) magnets. Due to the observed threshold character of LIFO, the patterned features can be small comparable to the radiation wavelength (~λ/10). This finding is expected to allow making the extreme features (down to 15-20 nm) and thus gives a potential advantage for using such directly patterned magnetic media in future storage data systems with ultrahigh densities ( ~ 1 Tbit/in²). The first experiments on formation of the extreme features by use of LIFO have been performed.

Magnetic junction is considered which consists of two ferromagnetic metal layers, a thin nonmagnetic spacer in between, and nonmagnetic lead. Theory is developed of a magnetization reversal due to spin injection in the junction. Spin-polarized current is perpendicular to the interfaces. One of the ferromagnetic layers has pinned spins and the other has free spins. The current breaks spin equilibrium in the free spin layer due to spin injection or extraction. The nonequilibrium spins interact with the lattice magnetic moment via the effective s-d exchange field, which is current dependent. Above a certain current density threshold, the interaction leads to a magnetization reversal. Two threshold currents are found, which are reached as the current increases or decreases, respectively, so that a current hysteresis takes place. The theoretical results are in accordance with the experiments on magnetization reversal by current in three-layer junctions Co/Cu/Co prepared in a pillar form.

In this work results of investigated films (Ni22ACo75A) x20L are submitted on the basis of which it is possible to say about their use as sensor systems in magnetic fields with the certain magnetization. Results of researches have shown structure of interfaces in volume of a film under influence of external factors and observable huge magnetic contrast in measurements of intensity of second harmonic generation. It was obtained out-of-plane anisotropy signal by means of simple magnetooptical Kerr effect techniques, which explaining by existence of uniaxial anisotropy, which is connected with the general direction of magnetization of domains in volume of film.

We designed the laboratory automation for the ferroelectric thin films investigation, which differs from analogous by open architecture. This equipment is quite adopted with hardware and software of the leading companies (e.g., GPIB boards and LabView National Instruments) in the field of measuring technique and systems of data acquisition. It makes possible to carry out measuring of basic characteristics of ferroelectrics: studying the ferroelectric hysteresis, determining pyroelectric coefficient by static and quasy-static techniques, taking magnitude of remanent polarization, measuring dielectric constants, measuring the specimen electrical conductance. The measuring system has open architecture and it is easy to readjust it to solve specific problems including applications, for example, optimization of technological processes of ferroelectric films fabrication for memory devices or uncooled focal plane arrays. Basing on this measuring system there were developed several methods which give an opportunity to improve the comprehension of processes in ferroelectric systems from physical point of view.

The measurements of ferromagnetic resonance spectra of tangentially magnetized arrays of micron size rectangular particles of permalloy produced by electron-beam lithography are reported. In contrast to continuous films, the spectra of arrays include a number of additional resonance peaks associated with spin-wave modes in the particles. The number of the peaks and their position depends on the angle between the direction of the bias magnetic field and the array axis. The magnetic structure of the particles was investigated using magnetic force microscopy. Magnetization reversal processes of the array were investigated using magneto-optic Kerr effect.

The structure and magnetic properties of thin nickel films grown by direct current magnetron sputtering on GaAs(100) and Si(111) substrates were studied by means of ferromagnetic resonance (FMR) method, magnetooptic Kerr effect (MOKE), atomic force microscopy (AFM) and X-ray diffraction (XRD). Dependence of the properties on substrate location inside flame zone during deposition was shown. Possibility of changing of the films' texture by varying of potential of the substrate during deposition was shown.

Dependence of the easy magnetization axis switch and domain structure in Fe films grown on GaAs(100) substrates on the growth temperature T_S and deposition rate υ was investigated. The easy magnetization axis direction was determined from ferromagnetic resonance measurements in tangentially magnetized Fe films. It was found for films grown at substrate temperature T_S ≤;140°C that with decreasing films thickness t smaller some critical thickness t^* the easy magnetization axis direction switches from [100] to [110] crystallographic axis while for films grown at substrates temperatures T_s>140°C the easy magnetization direction was along [100] axis at decreasing the film’s thickness down to 10 Å. The critical thickness t^* of “switched” film nonmonotonically depends on the deposition rate and was determined at t^* ≈ 21, 15 and 28 Å for deposition rates υ ≈1.4 ; 3 and 4 Å/min, respectively. Domain structures in FeGaAs(100) films are discussed.

We analyze the possibility for simultaneous adequate treatment of angular dependencies of the X-ray diffraction reflectivity and photoelectron yield (X-ray standing waves method) in order to extract the structural characteristics of semiconducting materials with ultra fine inclusions. Facilities of such an approach for evaluation of the degree of structural perfection of the layers, the phase shift of upper layers with respect to the buffer, the lattice parameters of particular layers and interfaces between them are demonstrated within the analysis of heterostructures based on the Si matrix with the Si_1-xGe_x quantum wells and on the GaAs matrix with the InAs quantum dots.

This work is devoted to the investigation of the magnetization reversal of microstructures directly in the magnetic force microscope (MFM) when the external field on the sample is created with an electromagnet installed into the microscope. By using special samples containing Co ferromagnetic micropatterns it was shown that the magnetization reversal of the tip of the microscope in the high magnetic field led to the essential transformation of the MFM images of planar magnetic microstructures. The computer simulation of the corresponding MFM images confirmed this conclusion. The analysis of the experimental MFM images of Co micropatterns obtained at the magnetic field in the range from -2000 up to 2000 Oe allowed us to estimate the coercivity of magnetic tips. The knowledge about the tip magnetic properties and computer simulation gave a possibility to interpret the MFM images of the samples in the strong magnetic field more correctly.

Experimental and calculated results of the investigation of electromagnetic field distribution including its polarization characteristics in the vicinity of the nanostructures are presented. Experimental investigation was realized by aperture type scanning near field optical microscopes (SNOM) which operated in collection mode and provided both high spatial resolution and large scanning range. Shear force detection was used for the control of aperture to surface gap. Normal resolution which allows resolving 0.3 nm height surface steps was demonstrated for this gap control system. Theoretical computation of electromagnetic field distribution was realized by finite-difference time-domain (FDTD) method. Experimental three-dimensional maps of intensity and polarization distribution as result of light diffraction at nanoaperture in metal screen, dielectric and metallized nanocylinders were obtained. The qualitative difference between the orthogonal polarized component distributions near nanoaperture in aluminium screen was experimentally shown. The electromagnetic field concentration in the proximity of the dielectric nanocylinders was observed. This observation gives good fit with the results of FDTD computations. Spiral type electromagnetic field distribution pattern was experimentally observed in the proximity of metallized nanocylinders, which is unexpected from both experimental and theoretical points of view.

GaAs-based heterostructures containing the layers with InAs quantum dots were studied by high-resolution X-ray diffraction and reflectivity measurements. Their structural parameters were derived by theoretical analysis of the measured data. The parameters derived from the diffraction and reflectivity measurements agree well with one another, which indicates that structural data yielded by the combination of such measurements can well be deemed plausible.

Photoluminescence technique is developed for characterization of resonant-tunneling diode structures formed of the GaAs/AlGaAs long-period superlattices in process of fabrication, which allows to estimate quality of the fabricated structure after the main stages of the technological process, including the MBE growth of multi-layer structure, lithography and annealing. The long-period multiquantum-well structures are promising for development of a new kind of solid-state intersubband-transition devices emitting the narrow band radiation in far infrared. This PL technique permits the corrections of the technology parameters to grow the structures with required properties and high homogeneity and can be used at room temperature as well as at low temperature.

Structural characteristics of semiconducting heterostructures AlGaAs/GaAs/AlGaAs containing either single quantum well or two quantum wells separated with a thin AlAs layer are estimated by means of the double-crystal X-ray diffractometry. It is found that an additional Si-doping of outer barrier layers results in the formation of abrupt (less than 2 nm) interfaces at quantum wells.

Tilted-axes YBCO thin films were deposited on NdGaO₃ (NGO) substrates with surface inclination from the standard (110) crystallographic plane. All deposited films were epitaxial with the (001) YBCO plane aligned with the {110} planes of the substrate. Structural and morphological studies revealed three angular ranges of the film formation: a small-angle “vicinal” range, where the films to not differ much from films deposited on (110) NGO; a high-angle range, characterized by “step bunching” during the thin film growth; and an intermediate range, providing very smooth films with the best crystal structure. Differences in film morphology and structure are probably due to an increasing density of seeding centers on the surface of tilted-axes substrate with an increase of inclination angle. The reason for the high-quality film formation in the intermediate range is probable the matching of the density of seeding centers and the diffusion length of the atoms on the surface. This model is corroborated by differences in the intermediate range angles for different deposition techniques. The intermediate range thin films showed also the best electrical properties (T_c, J_c(77 K), R_s(77K, 10 GHz).

The room temperature photoreflectance (PR) investigation of optical transitions in Al_0.2Ga_0.8As/GaAs/Al_0.2Ga_0.8As single and coupled quantum wells is presented. The structures were grown by molecular beam epitaxy for different barrier thickness and quantum well width. Three kinds of spectral features were observed in PR spectra: sharp line connected with GaAs band gap (1.42 eV), Frantz-Keldysh oscillations near Al_0.2Ga_0.8As band gap (1.71 eV) and features originated from electron-hole transitions in quantum well. The energies of observed transitions have been compared with the results of envelope function calculations.

The functioning of the linear step electrostatic film micromotors with the short controlling pulse (less then 100-200 µs) is studied to create nano- and micro-positioners. The theoretical study of the step movement of the given mass in this time frame is carried out. The results of the experimental studies of the multipetal reciprocal micromotors created on the basis of La modified Ba_0.5Sr_0.5Nb₂O₆ ferroelectric films with 1-3 μm thickness are shown. The petals were made of beryllium bronze. It is shown that the electrostatic rolling can last less than 50 μs, and the process of separating two surfaces (the metal and the ferroelectric) can last less than 1 μs. These parameters allow one to operate the micromotor at 1-10 kHz frequency, and the propulsion force in the beginning (the first 20-100 μs) of the electrostatic rolling can be as high as 1-10 N per 1 mm² of the rolling surface with the voltage pulse amplitude of 40-50 V. The possibility of obtaining moving plate (MP) step in the nanometer range is studied, as well as the precision of these steps during the continuous MP movement with the different clock frequencies and durations of the voltage pulses. The recommendations are given to improve the accuracy and the speed of the positioning in the nano- and micro-movement range. Possible fields of micromotor application are micromechanics, including precision micromechanics, microelectronics, microrobots, microoptics, microscanners, micropumps (e.g. in the jet printers), micro flying vehicles etc.

A simple computationally effective semi-analytical macroscopic technique of self-consistent calculations of the electrical properties of the MOS structures with ultra thin high-k gate oxide film is developed. Calculated gate voltage - gate leakage [substrate-injected direct and Fowler-Nordheim (FN) tunneling] and gate capacitance characteristics are presented and discussed. The Si/oxide band offset is shown to be the main parameter affecting leakage. The stepwise behaviour of the I - V characteristics is predicted. A contribution of the FN injection is discussed.

The nanometer scaling of metal-oxide-semiconductor (MOS)-devices requires a transition to thin and ultrathin gate insulators. Their tunneling conductance in such insulators essentially changes of the process of the minority carrier (MC) generation. In n-Si-MOS-structures with a insulator thickness below 100Å the tightly growth and sharply dropping peak is appeared on the time dependence of the generation current I_g(t). The peak is completed a transition of a MOS-structure to the equilibrium inversion state. In this state the stationary tunnel current I_t∞ flows through a MOS-structure. The amplitude peak and its position in the time strongly depend from the structure construction, its prior history and external factors and can to change in wide limits. The sequential description of phenomenon is based on presentations about a impact ionization of the MC band, tunneled through oxide in semiconductor by heat electrons. The developed algorithm allows to divide of the contributions of generation and tunnel current component in dependences I(t, V_g) and to characterize of oxide tunnel conductance. The algorithm too allows to determine set of base electronic characteristics of MOS-structures: the impact ionization coefficient α, sign and integral density of fixed charge in a oxide, a rate of the MC generation and a velocity of the surface recombination, and the time evolution of the semiconductor surface potential. These data are base for the physical diagnostic of degradation mechanisms of the semiconductor/insulator interface region. The strong dependence of kinetics of the thermo-tunnel generation of MC from a composition of a surrounding medium can to use for a creation of gas sensors of new type.

The ensemble Monte Carlo algorithm for simulation of charge carrier transport in short channel MOSFET was developed. The mobile charge carrier concentration and electrostatic potential calculation procedures were worked out. The drain current increasing mechanisms caused by secondary holes transport in short channel MOSFET were considered. It was found out that at channel length about 0.1 μm the influence of secondary holes transport is quite significant.

A method of a computer analysis of MFM images was developed. The computer analysis of MFM images of separate ferromagnetic single-domain nanoparticles placed on a nonmagnetic substrate was carried out. The shape of an MFM tip and the trajectory of its movement were taken into account. The aureoles were found in the magnetic contrast of MFM images simulated for the lifting mode. The conditions and the reasons of the appearance of these aureoles were discussed.

This paper suggests using directed flows of low-temperature plasma formed by high-voltage gas discharge to obtain micro and nanostructures on substrate surface. The algorithm and software have been developed which make it possible to automate the process of calculating optimal values of the process parameters by etching microstructures in high-voltage gas discharge plasma. The difference between the experimental results and design data obtained as a result of simulation amounted to less than 10 per cent when investigating the following materials: silicon, silicon dioxide, silicon carbide, diamond films.

The description of dynamics of particles size distribution function (PDF) in processes of new phase formation is important task in various technologies. Moments method is one of modern approaches which meet demands of accuracy and moderate usage of computer resources. Modified moments method which permits one to describe correctly both particles growth (in results of nucleation, coagulation and surface reactions) and gasification is proposed and developed in this work. Proposed approach connect correctly balance between growing particles and chemical precursors in contrary to present state of art. This is important when rates of particle decomposition, gasification, combustion are compatible with the rate of particle growth. The model calculations were carried out to show that approach gives incorrect rate of soot formation in the mentioned above case. Modified method of moment was applied for simulation of hydrocarbons combustion and conversion. In particular steam reforming of methane was simulated in details. The processes of soot formation include polycyclic aromatic hydrocarbon (PAH) lumping mechanism, soot formation in results of PAH coagulation in three dimensional structures, coagulation of soot particles, soot particles growth and gasification due to surface chemistry. Chemical mechanism also includes the general chemistry of methane decomposition with PAH and soot precursors formation. The comparison of theoretical and experimental results demonstrates that developed approach can describe species concentration and PDF evolution adequately.

For description of the diffusion process in a temperature field at the constant temperature gradient in semi-infinite media from an extended source of infinite extent and an instantaneous plane source the simple formulae taking into account the temperature dependence of diffusion coefficient is proposed. The analytical solution of the equation describing thermodiffusion for same conditions for gaussian form source is given. Since in this solution the temperature dependence of diffusion coefficient is not taken account the limits of its applicability is examined.

A model of non-equilibrium out-diffusion of dopant from ion-implanted layer at rapid thermal annealing has been offered. The model is based on supposition of dependence of out-diffusion activation energy on the non-equilibrium coefficient characterizing the system non-equilibrium state from the point of view of the ratio of components concentration.

The hydrogen diffusion model in GaAs in conditions of an intense flow of penetrating atoms has been developed. It is shown that the formation undersurface diffusion barrier layer from immobile interstitial molecules of hydrogen reduce probability of atoms penetration into crystal and rate of their diffusion in GaAs, and influence on the process of shallow- and/or deep-centers passivation. It is exhibited that the influence of diffusion barrier should be taken into account at optimum mode selection of GaAs structure hydrogenation.

A hierarchical approach to the construction of compound distributions for process-induced faults in IC manufacture is proposed. Within this framework, the negative binomial distribution is treated as level-1 models. The hierarchical approach to fault distribution offers an integrated picture of how fault density varies from region to region within a wafer, from wafer to wafer within a batch, and so on. A theory of compound-distribution hierarchies is developed by means of generating functions. A study of correlations, which naturally appears in microelectronics due to the batch character of IC manufacture, is proposed. Taking these correlations into account is of significant importance for developing procedures for statistical quality control in IC manufacture. With respect to applications, hierarchies of yield means and yield probability-density functions are considered.

Power consumption regularities of the most perspective quasi-adiabatic base logic gates are investigated by method of computer modeling. The effect of abnormal high power consumption in a range of low frequencies is discovered and explained; the method of its neutralization is offered. It is revealed, that in a range of high frequencies energy dissipation in gates decreases at reduction of clock frequency more poorly, than under the law 1 / f . The mechanism of this anomaly is found out. The established laws a power consumption of the base logic gates allow to choose the compromise between power consumption and speed, optimize power characteristics of base gates. It's also allowed to predict their improvement at quality improvement of technology.

We investigated dynamics of entangled states on the basis of multiple-quantum (MQ) NMR methods. A time evolution of MQ coherences of nuclear spins coupled by the dipole-dipole interactions (DDI) in solids is simply connected with dynamics of quantum entangled states. We studied analytically dynamics of the entangled states for two- and three-spin systems. In this case dynamics of the quantum entanglement is uniquely determined by the time evolution of MQ coherences of the second order. The real part of the density matrix describing MQ dynamics in solids is responsible for MQ coherences of the zeroth order while its imaginary part is responsible for the second order. Thus, one can conclude that dynamics of the entanglement is connected with transitions from the real part of the density matrix to the imaginary one and vice versa.

We present the scheme of compatible quantum information analysis of the quantum key distribution (QKD) protocols, which give answers to the following questions: is it possible to improve the quantum bit error rate (QBER) of the 6-state protocol by employing more states, up to infinity, and can we essentially improve the QBER if the multidimensional Hilbert space with dimensionality more than 3 is used? Also, a novel quantum key distribution (QKD) protocol, based on all unselected states of a quantum system, which set the alphabet with continuous set of letters, is proposed. Employing all states of the Hilbert space leads to the maximal quantum uncertainty of transmitted states and therefore an eavesdropper receives the minimal amount of information. For the case of two-dimensional Hilbert space, our protocol allows secure transmission at the error rate higher than that one for the BB84-protocol and comparable with the characteristics of the best known QKD-protocols. However, with increasing the dimensionality of the Hilbert space the critical error rate for our protocol increases and in the limit of infinite-dimensional space the protocol becomes non-threshold.

Uncontrollable interaction between qubits can completely destroy coherent state of quantum computer. We study such decoherence processes by numerical simulation of quantum computer operation performer adder algorithm. A polynomial procedure of avoiding such decoherence was also simulated.

An approach to coherent parallel computing on finite spatial rotations is considered. It is shown that such rotations are elements of 4-dimensional (4D) space and to design any algorithms with them we need to change Boole logic to more complicated rotational one. The latter is provided by formalism of Cayley-Klein parameters, which is compatible with geometric Clifford algebra and all its elements of pure and mixed grades: vectors, scalars, paravectors, quaternions, spinors, etc.

Multiparametric statistical model providing stable reconstruction of parameters by observations is considered. The only general method of this kind is the root model based on the representation of the probability density as a squared absolute value of a certain function, which is referred to as a psi-function in analogy with quantum mechanics. The psi-function is represented by an expansion in terms of an orthonormal set of functions. It is shown that the introduction of the psi-function allows one to represent the Fisher information matrix as well as statistical properties of the estimator of the state vector (state estimator) in simple analytical forms. A new statistical characteristic, a confidence cone, is introduced instead of a standard confidence interval. The chi-square test is considered to test the hypotheses that the estimated vector converges to the state vector of a general population and that both samples are homogeneous. The expansion coefficients are estimated by the maximum likelihood method. The method proposed may be applied to its full extent to solve the statistical inverse problem of quantum mechanics (root estimator of quantum states). In order to provide statistical completeness of the analysis, it is necessary to perform measurements in mutually complementing experiments (according to the Bohr terminology). The maximum likelihood technique and likelihood equation are generalized in order to analyze quantum mechanical experiments. It is shown that the requirement for the expansion to be of a root kind can be considered as a quantization condition making it possible to choose systems described by quantum mechanics from all statistical models consistent, on average, with the laws of classical mechanics.

The scanning (step-and-repeat) and projective (simultaneous) methods of ion-optical implantations of single phosphorus ³¹P ions in hetero-structure Si/Si_xGe_1-x are offered and analyzed with the purpose of formation of qubits of the solid-state quantum computer. Opportunities axial-symmetric electromagnetic objective lenses and existing sources of highly charged ions with reference to the given problem are considered. It is shown, that combined axial-symmetric electromagnetic lenses have advantage in comparison with electrostatic lenses. The combined electromagnetic objective having record small axial aberrations is designed. The optical scheme of scanning single ion implanter with such objective is offered. The critical parameters determining productivity of ion-optical implanter are allocated. They are the allowable lateral discrepancy of localization of implanted ions, a chromatic aberration of an objective, brightness of an ion source and the multiplicity of a charge of doped ions. The formula connecting these values is deduced. Requirements to sources of highly charged ions and the offer on search of new sources of highly charged ions and projective ion-optical schemes of single ion implantation are formulated.