This paper examines the theory of digital algorithmic measurement (DAM) for a signal microprocessor (SMP) in three aspects: (1) as a method of algorithm SMP structures designing; (2) as a process of REE analog functions simulating, and (3) as a method of functional measuring. The theory is based on a broad concept `measuring' and its corresponding concept of property measuring scale (in the form of metrological coding ADC scales and relational system for a SMP) and on system homomorphism and equivalence ratio, which are considered for various digital systems of mathematics. It was shown that the ideas of modular arithmetic can be used for DAM, thus ensuring accurate measuring. The DMS is described in terms of signal graphs.

The design and control system SEMICROT is a program packet, for use on an IBM- compatible PC. Basically, the program-packet aids the designing and manufacturing of microwave varactor diodes. Lately, step recovery diodes and tuning diodes were manufactured with the aid of SEMICROT in the RIT.

The paper presents the results of research work carried out as an introductory effort toward development of a high level synthesis system. The restrictions imposed on the behavioral specifications and the language extensions provided to control the synthesis process are discussed. The internal machine representation of the initial specification is presented.

Simulation of submicrometer silicon p-channel MOSFETs using the Monte Carlo (MC) method is presented in this paper. A two-dimensional device simulator has been developed to investigate hot-carrier, nonstationary transport. The space-charge effects are included through the self-consistent 2-D Poisson solution. Ionized impurity, inter- and intravalley scattering with acoustic and nonpolar-optical phonons as well as impact ionization (II) have been taken into account in our model. The classical partial diffusive model is employed for surface scattering process. It was found that the average drift velocity indicates an overshoot at the pinched-off region of the device. The comparison with results of drift-diffusion (DD) simulation has shown the negligible difference in I-V curves obtained by the MC and DD calculations for devices with channel length greater than 0.2 micrometers .

This paper addresses development of application specific integrated circuits in field programmable technologies using programmable logic devices (PLDs). Problems in designing on PLD devices are discussed, with emphasis on device-specific constraints. As a basic shortcoming of the existing automated design tools, lack of high level design procedures optimizing the actual circuit with respect to the target PLD device architectural capabilities is indicated. To support more effective utilization of PLD device mapping, special systems that exploit argument reduction and generic logic decomposition are proposed. Problems that have been encountered in designing a PCM frame synchronization circuit are discussed, to illustrate the whole spectrum of decisions to be made by the designer.

In this paper we propose one of the multilevel logical synthesis methods -- decomposition -- as a convenient technique for implementing combinational functions in many types of programmable devices. It appears that it is possible to exploit unique features of all architectures preserving homogeneity of method and only modifying the hierarchy of the objective functions and constraints in the decomposition procedure.

The physical effects in SOI MOSFETs such as the floating substrate regime in `thick' film, accumulation of excess holes in `thick' and `thin' film for the negative voltage at the back gate, the influence of the fixed surface charges at the front and back interface Si-SiO₂ are investigated using two-dimensional numerical simulation. The dependence of the current- voltage characteristics of SOI MOSFET on the physical and technological parameters are analyzed. Some specific effects such as kink-effect, histeresis of drain characteristics, drain current overshoot, and their dependences on the switching speed are investigated. It is shown that thin film SOI devices with excluding floating substrate effects must be used for high speed VLSI. The switching characteristics of the different construction of the SOI/CMOS structures are simulated and compared. It is shown that thin film 3-D SOI/CMOS make a good choice for high speed VLSI.

A single stage GaAs monolithic amplifier chip for L-band has been designed and fabricated. The design includes a 1 micrometers multifinger transistor gate with polyamide bridges for the source interconnections and overlay capacitors with sputtered silicone nitride dielectric. An RC feedback has been used to provide microwave gain of 9 dB within the band. Single supply of 10 V is required. The biasing point of the transistor can be set by proper selection of the source resistors during bonding.

The planar doped barrier diode being majority carrier semiconductor device has promising application areas in high-frequency and microwave circuits. The paper reviews the main features of diode structures. The different current conducting processes as the thermionic emission, the diffusion, and the tunneling are treated. The design rules for the barrier height also are given, and our own experimental results reported. Microwave diodes and zero bias detectors have been fabricated in RITP on layer structures grown in TUT.

A 1 micrometers gate GaAs MESFET designed for the lower X-band frequencies has been fabricated and characterized. A MOCVD-grown, Se-doped channel layer with 3900 cm²/Vs carrier mobility and a recessed gate structure resulted in a maximum device transconductance of 180 mS/mm. Transistor microwave performance was characterized by the measured gain of 8 dB and noise figure of 3.5 dB at 9.375 GHz. S-parameters measurements in the frequency range 1 divided by 12 GHz allowed for evaluation of small signal equivalent circuit parameters.

The detailed investigations of degradation processes, their characterization and understanding of mechanisms responsible for degradation is of great technological interest, both from the fabrication point of view, and as a long-term reliability concern. Some of the effects usually need investigation in the completed MOS transistor structure (hot carrier degradation, threshold voltage, and channel mobility deterioration), but others should be studied with the special test structures so that effects can be investigated independently (electromigration, radiation effects, oxide wear-out). The paper presents a review of problems related to reliability of VLSI ICs, degradation processes, and their characterization.

A simulation method of development processes of LSIC element failures, based on the introduction of surface acoustic waves (SAW) into a semiconductor chip with supply voltage and electric test actions applied simultaneously is proposed. It is shown that the degradation process intensification is achieved due to the increase of the degree of the state nonequilibrium of crystal lattice atoms resulting in the decrease of the threshold energy necessary for their participation in the degradation process. An analytical expression allowing the evaluation of test regimes, and, in the first place, the SAW amplitude, ensuring carrying out the test for a given period of time has been obtained. A test cell, the test results are given.

In this paper an automated system for measuring C-V-F-T characteristics at the frequency range of 10^-5 - 1000 Hz and a system for measuring quasistatic C-V characteristics are presented. The results of the low frequency capacitance and the quasistatic measurements on MOS structures with amorphous silicon are presented. On the basis of these measurements, parameters of the structure were determined. Low frequency measurements of capacitance were also used to obtain information about deep levels.

Some basic research problems occurring during the use and the development of this part of the SEWTIDUE expert system, which assists the digital circuits functional diagnosis, are discussed. The basic problem is constructing a suitable information net model of the digital circuit. The application of the system to specific analysis of the circuit diagnostic properties are illustrated in the example.

The paper presents some problems of implementation ANSI/IEEE Std 1149.1 worked out in the Industrial Institute of Electronics (PIE) microcontroller board. Diagnostic properties of some special hardware solutions and examples of testing procedures are described. Testing was performed with the help of the PIE diagnostic bus analyzer.

The paper presents basic properties of digital circuits, with a boundary scan testing (BST) subsystem in the circuit architecture. The paper describes the operation and states for test access port controller (TAPC) built in the subsystem. A self-test procedure is presented, based on pseudo-random test generation and signature analysis, done by linear feedback shift registers (LFSR), configured with boundary scan register cells. Characteristics of the pseudo- random signal generator were obtained by simulation method.

The theoretical basis of the research for the most advantageous way for isolation of the circuit clusters are given. The formal description of the circuit information net model, being the basis on the inference engine about the testability of the circuit are presented. The work has the goal of improvement of the computer-aided design of the digital circuits with the redundancy and/or built-in self-test.

In the paper, the testing method of DTMF circuits applied for dialing signal generation in telecommunication systems is described. The method enables determining: frequency, amplitude, and harmonic distortions of DTMF signals generated by tested integrated circuit. It was developed by the authors. Application of digital IIR filters and Fourier transform provides good accuracy and constant metrological parameters of the test system in connection with short test time. As a result of the developed method, the automatic telephone test system TAT- 92 controlled by a personal computer is designed. This paper describes the problem, the solution, and the comparison of new method and classical method, based on analog filters.

This paper considers a new algorithm for an integrity enforcement in a cellular database system. The algorithm is based on a forward checking strategy and on a group code propagation technique for looking ahead. It enables a reduction of searching space by cutting off partial results which have no extension to the full mapping. The presented algorithm is an extension of the associative forward checking algorithm. The new version offers more restrictive processing power, but additional time for several new operations is required.

Development of microelectronics is taking place at a very fast rate all over the globe, including India. New technologies are introduced at very short intervals in order to capture the consumer market. It is essential that these technologies are managed properly at the macro level in order to bring the desired results. Microelectronics plays a very vital role in office automation for achieving cost effective results in a highly competitive environment. Introduction of various facilities like laser printers, photo copiers, dictaphone-selectronic boards, electronic telexes, teleconference rooms, telephone answering machines, computer, word processors, sensors, etc. have all revolutionized the industry. Keeping the above in view, the present and future status of microelectronics, with special emphasis on its role in office automation in India, are discussed in detail in this paper.

P-CAD's CUPL is one of the most popular tools for translating a functional description of the circuit into its corresponding PLD-based structure. However, CUPL's input format describes a circuit at the very low level. Moreover, it requires an early selection of target PLD devices that is particularly inconvenient when more complex circuitry is considered. Therefore, designing of large circuits with the help of CUPL is tiring and time consuming. In the paper, another concept is investigated. Behavioral description of the circuit is formulated using procedural CHDL called UPLAND. Then, this description is automatically translated into its corresponding CUPL input format where target PLD devices are optional. The paper introduces UPLAND and outlines the principles of CUPLAND compiler work. An example is given which illustrates CUPLAND efficiency.

Low-frequency noise measurements were performed on grain boundaries that were Czochralski and Stepanov grown, obtained by diffusion `sticking' of different slices of silicon, and polycrystalline resistors, diodes, and transistors with polycrystalline emitters. It was found that in different cases the typical features were that both the potential fluctuation model and mobility fluctuation model were observed. Different contributions to the current noise made grain boundaries that were situated parallel and perpendicular to the carrier's current. Some discrepancy between existing noise models, real noise electrical circuit, and current noise temperature dependence of polycrystalline resistors were shown. These facts lead us to regard conclusions of existing models with care. Investigations of diode and transistor current noise show that the peculiarity of polycrystalline silicon demonstrates itself not only in the properties of base regions but also in the p-n junction regions.

The electrical parameters of polysilicon-contacted emitters are investigated. The emitter-base junction C^-2-V plots demonstrated an anomaly because of charge occurrence at the polySi-monoSi interface. A critical analysis of well-known methods for emitter series resistance determination is carried out and the new method, which coupled the dc and ac measurement's dignities, is described. The procedure of emitter low-frequency noise determination is proposed and the experimental results received by this manner are presented.

Results of experimental investigation of the current-induced resistance change in polycrystalline silicon films (PSFs) with doping concentrations of 2 (DOT) 10¹⁷ cm^-3 -2 (DOT) 10²⁰ cm^-3 are presented. For the concentration of 1 (DOT) 10¹⁹ cm^-3 and 2 (DOT) 10¹⁹ cm^-3 the effect of current-induced resistance increase is found and preliminary discussion is made. The application to monolithic delay line (MDL) is described and the main electrical parameters and characteristics of designed ICs are compared with known MDLs' series.

A 2-D electrothermal model of thyristor structure with emitter shorts is presented. It is formed by three coupled submodels: electrical, heat transfer, and heat dissipation. The heat dissipation submodel takes into account heat generation caused by ohmic losses and recombination, as well as the inner heat transfers caused by thermoelectric effects. The results show how the presence of emitter shorts influences the work conditions inside the considered thyristor.

Acoustic power amplifiers have low efficiency. It can amount to 60 - 70% in ideal conditions. Due to this efficiency, high power amplifiers weigh a lot and are large in size. Improvement of the efficiency of an acoustic amplifier can be achieved through supplying a given amplifier with a voltage that is proportional to the input signal. Our paper describes how to increase the efficiency.

The example of ferroelectric films of barium strontium niobate (BSN) deposited on a silicon substrate with thin silicon nitride sublayer was used to show that the specific features of charge accumulation process in metal-ferroelectric-insulator-semiconductor (MFIS) structures depending on the parameters of insulator and ferroelectric layers manifest themselves in three mechanisms: (1) injection writing, (2) polarization writing, and (3) polarization -- injection mechanism at which the polarization in ferroelectric enhanced the injection of carriers from the semiconductor-insulator interface. The details of manifestation of each mechanism were analyzed.

In this paper high-voltage MOS transistors structures fabricated using a standard CMOS technology and a special design technique are presented. The design, characterization, and modeling of n-MOS, with the breakdown voltage of 50 V, and p-MOS, with the breakdown voltage of 130 V, fabricated using a standard 3 micrometers CMOS process are discussed. In addition, the possibility of high-voltage buffer circuit realization which is composed of n-MOS and p-MOS transistors, operating with the supply system U_SS equals 0, U_DD equals 5 V, U_E equals - 40 V, self-isolated from low-voltage components is demonstrated.

An abridged text of a report on design and characteristics of a new three-lead temperature- current sensor with application of parametric bandgap-calibration is presented. The main distinction of the sensor consists of its output characteristic's zero coincidence with Celsius scale zero. Those fields of the sensor application are considered which are realized in a more complicated way from the point of view of circuitry and are of poorer quality in case of two- lead sensor analogs of a PTAT type (proportional to absolute temperature). Functionality of the proposed thermosensor is considerably widened.

The hybrid selective gas analyzers for NH₃ concentration control with sensitive elements such as poly-Si films and MOS-transistors with threshold voltage, depending on the hydrogenous concentration level, were worked out. Resistance-to-frequency transducers on the base of cascode circuits with intrinsic positive current feedback were fabricated.

In the paper are presented the new results concerning the investigations of existence peak effect in high temperature oxide superconductors. The measurements of anomaly dynamical current-voltage characteristics of high temperature oxide superconductors have been performed in the function of transport current amplitude, temperature, and also magnetic field sweep rate. The experimental results indicate strong influence of these parameters on the magnitude of peak effect which allows the possible application of this effect in the device for detecting magnetic field rotation velocity of the superconducting machine rotor.

Thick film RuO₂, AuPt, and thin film Pt heaters of different shapes were manufactured to enable operation of a semiconductor gas sensor at elevated temperatures. Different bonding techniques, i.e., soldering, thermocompression, and ultracompression using Au, Pt, PtRh, Al, and Cu wires, were adopted. Surface temperature distribution was determined with the help of thermovision and point thermocouple measurements. Aging tests reveal good performance of both thick and thin film heaters at temperatures of about 300 degree(s)C. A new method of heater temperature control is described.

The cather-type silicon pressure sensor for biomedical application is presented. A new cutted piezoresistors configuration of the high sensitivity pressure sensor is proposed.

By means of Raman scattering spectroscopy and selective etching, point defect redistribution and change of crystalline matrix in annealed GaAs crystals was discovered. The temperature interval of most structure changes for each group of investigated crystals has been defined.

Interdigitated planar photodetector structures were fabricated on semi-insulating GaAs material using ohmic-ohmic and Schottky-Schottky contacts. The dc and pulse response performance of the devices indicate that the devices with Schottky contacts are more suitable for high-speed photodetection and pulse generation. The differences between the two types of devices are interpreted with the difference in contact type, trapping mechanisms, and contact resistance effects.

Gettering directly included into a technological process of GaAs epitaxial building-up is described. The process of gettering consisted of the formation of TaAs layer of 5-7 micrometers thickness and its annealing in H₂ followed by the etching of the layer. It was found that introduction of gettering annealing into the process of the epitaxial structure build-up leads to a decrease in the concentration of the electrically active deep-level centers.

The contamination of silicon wafers by carbon has become of great interest due to the fact that this effect seems to be basically impossible to avoid during plasma etching and that it is not yet known what ICs parameters it can influence. The results prove that presence of carbon in the silicon subsurface region has enormous influence on the electrophysical properties of the oxide as well as SiO₂-Si interface. Both breakdown and interface properties are degraded. Clear evidence is found that the observed effects are caused by carbon contamination and not by structural damage of the silicon substrate.

The paper deals with the radiation hardness of the Si-SiO₂ system -- the basis of advanced MOS VLSI integrated circuits. While the radiation-induced behavior of such crucial Si-SiO₂ parameters as surface and oxide charges have been intensively investigated for many years, the radiation aspects of the dielectric strength of thin oxide films has not been investigated. This work describes experiments carried out in order to determine radiation hardness of silicon dioxide dielectric strength. The results show that the (gamma) -radiation does not change the oxide reliability parameters up to the dose of 10 Mrad. On the other hand, transient processes which pass before breakdown occurs are strongly affected in irradiated oxides. Radiation-induced changes can also be responsible for the annihilation and generation of high-field defects which affect the parameter distributions in the near-intrinsic range.

Computer calculations of electric field distribution in VLEDs and FETRODEs with cylindrical and prismatoidal geometry are presented. Plasma etched prismatoidal silicon tips are shown. A new TV flat screen with FETRODEs (or VLEDs) has been proposed.

The electrochemical etching of silicon in electrolytes is proposed as a method for realizing three-dimensional sensor and actuator elements. Preparation and properties of a porous silicon layer (PSL) were investigated. A single silicon crystal was converted into PSL by anodization in the solution of hydrofluoric acid and ethanol with different concentrations. He-Ne laser was used for the stimulation of electrochemical reaction on n-type silicon. As a result of photoelectrochemical reactions, many micropores are formed inside PSL and zig-zag in the thickness direction. This porosity structure has high chemical activity and variation. The composition of PSL was investigated by methods of secondary emission mass spectroscopy and infrared Fourier spectroscopy.

Etching of silicon has been examined in CBrF₃ plasma in a wide pressure range (2 - 100 Pa). Optical emission of CBrF₃ plasma was investigated in the visible range. Mass spectrometry was used for the studying of ion plasma composition and for the determination of the main etching products. Conditions for the high quality trenches were determined.

In the past several years, much progress has been made in neural network technology. Neural networks have been used in many applications of signal processing to classify different sets of patterns. This paper presents some of the trends relevant to application of neural technology. No comprehensive review of the state of the art is attempted. Rather, the emphasis is selectively on certain current trends, as new ideas, that in the author's opinion show promise for the future. However, the reader should note that neural network technology is in a state of flux with several alternative theoretical models and approaches. The paper deals with the practical aspects of the research in neural networks. The basic concepts of neural networks and progress in learning algorithms are briefly reviewed, followed by a discussion of the trends relevant to hardware implementations of these networks. Finally, hybrids comprising neural networks, expert systems, and genetic algorithms are considered.

The paper deals with the quasi-optimum placement and temperature estimation of heat dissipating components in hybrid power circuits. A placement is found when the extreme temperatures on the substrate are minimized. Whereas classical techniques require large computational effort, a method presented in this paper is simple and rapid. It couples two main ideas: a heuristic approach to the placement problem and a neural computation of temperature.

The growth kinetics, the structure, and the properties of films up to 25 nm thickness, obtained by thermal oxidation in dry oxygen of silicon substrates doped by phosphorus, are studied. It is shown that on a definite stage of oxidation, the anomalies connected with the structural transformations in oxides are observed in the kinetics, the change of oxide density, and the quantity of stresses in the system Si-SiO₂. The results obtained are explained on the basis of the silicon heterogeneous oxidation reaction suggested by the authors earlier.

The report is dedicated to the application of grazing-incidence x-ray diffraction in the inclined Bragg-Laue geometry for investigation of semiconductor superlattices (SL). It is shown that it provides depth-resolved information on the SL structure and can be used for express control of SL parameters. A new x-ray spectrometer for surface structure characterization of semiconductor materials is presented.

In this paper the results on the formation of submicron doped layers by multipulse light treatment are presented.

The plasma polymerization is one of the methods of resist film coating. It is known that polymer deposition rate has maximum value in the glow zone of discharge (GZD). But the activation of monomer molecules in GZD may lead to their considerable destruction. To keep the initial molecular structure of at least one monomer, the following experiment on copolymerization of two monomers was carried out. Inside the flowing tube reactor, the vapor of one monomer (for example, xylene) was filled in the glow zone of argon plasma, and the vapor of another monomer, (methyl methacrylate) was filled outside this zone in the lower part of the gas flow. The silicon substrate was placed perpendicularly to the reactor axis under GZD. The thickness of the polymer film was controlled by means of a laser interferometer. The experiment revealed that the film deposition rate is significantly greater for copolymerization of two monomers than for polymerization of each monomer separately when another one is not filled. Thus, the principal possibility of copolymerization of monomers in the after glow zone of discharge (AGZD) has been demonstrated. Moreover, only one monomer is activated in the plasma during this process, while the structure of another one is preserved.

Peculiarities of 30...100 keV P⁺ and Ar⁺ ion implantation into dry vacuum resist on the base of -pyrone have been studied by x-ray photoelectron spectroscopy and Rutherford backscattering spectrometry. Phosphorus atom distribution profile has been shown to have an anomalous shape with two peaks, one of which is situated in a region of projected range, while the other is on the sample surface directly. Radiation-induced diffusion and solid phase reactions leading to phosphorus organic coating formation of about 40..50 A^o in thickness has been revealed to occur during phosphorus ion implantation.

A novel diagnostic technique for the study of semiconductor surfaces based on laser induced microwave photoconductivity detection with high spatial and temporal resolution is described. Experimental data on nonlocal modification effects in laser produced scribing, doping, and annealing of ion implanted GaAs and Si are presented. Mechanisms of nonlocal structural and electric properties changers under modification are analyzed. Nonlocality phenomena are concluded to be universal for any strong modification procedure and very important for microelectronics technology.

The biosphere contains a myriad of substances which can influence or stimulate various aspects of the health and behavior of living organisms. Not surprisingly, in the last decade or so researchers have appreciated the potential of developing a range of molecular sensor technologies, designed to estimate and monitor biological and chemical substances with a view to eventually controlling the biological processes themselves. This development has been accelerated recently by the realization that molecular sensors offer considerable commercial potential. At the same time, it was quickly appreciated that such sensors could revolutionize several areas, including health care, pollution and contamination monitoring, agriculture, on-line monitoring and control of industrial chemical processing, and strategic and tactical monitoring of chemical warfare. This brief review considers the changing scene in molecular sensor research by reference to a few key examples.

The paper presents an overview on the present status of vacuum microelectronics and discusses the development trends of this technology. The overview is based on a concise description of the manufacturing technology and on detailed discussion of the exploitation parameters of such devices as microcavity vacuum tubes, pressure sensors for robot tactile sensing, lateral vacuum microelectronic logic devices (NOR and NAND), and fluorescent displays. The paper concludes with a short presentation of the development trends in VM and current activities of OBREP Research Centre in this field.

Schottky diodes often exhibit anomalous current-voltage characteristics at low temperatures with temperature dependent ideality factors and apparent barrier heights evaluated for the thermionic emission. In this paper theoretical expressions are first presented for the temperature dependencies of the ideality factor and the apparent barrier height for the thermionic-field (T-F) emission, including the bias dependence of barrier height. Expressions are also presented to evaluate the characteristic energy E_oo and the bias dependence of barrier height from the temperature dependence of the ideality factor. Model calculations have been performed using these expressions, and their results are compared with the available experimental data. It is shown that the mechanism responsible for the temperature dependent ideality factors and apparent barrier heights often is the T-F emission with anomalously high characteristic energies. The possible causes of the high characteristic energies are discussed.

It has been shown that during the implantation of some ions with the same energy but different charges, amorphous layers of different thickness are observed. To elucidate the reasons of the effect observed, new experiments using ellipsometric and electrophysical measurements have been carried out.

Unintentionally doped GaAs molecular beam epitaxial layers were grown using MBE equipment developed for research purposes. The process of surface treatment of the GaAs substrates is described. The MBE grown layers were characterized using temperature dependent Hall effect measurements, and low temperature photoluminescence spectroscopy. The occurrence of unintentional doping elements (C and Mn) are studied too. A novel method is proposed to reduce the amount of unintentional C resulting in an estimated concentration of C less than about a few times 10¹⁴ cm^-3.

We report the Y-Ba-Cu-O infrared (IR) transmittance, electron paramagnetic resonance (EPR) spectra and x-ray diffraction pattern evolution through transition of samples from oxygen disordered tetragonal O₆ to orthorhombic O_6.8 phase. The transmittance spectrum of the sample prepared by conventional technique and quenched in liquid nitrogen is considerably distorted by lattice defects. After thermal treatment, their concentration is reduced by interstitial oxygen redistribution and the spectrum acquires its natural shape. Further spectra evolution, considered as extra oxygen in-plane ordering, is in a good agreement with EPR and x-ray diffraction measurements. The possibility of Y-Ba-Cu-O films oxygen stoichiometry inspection by IR spectroscopy methods is discussed.

In this work, n-type neutron transmutation doped silicon irradiated by high energy, low dose protons have been investigated. Proton irradiation introduces deep energy levels in the bandgap of silicon, which act as recombination centers. Parameters of deep energy levels have been measured by the deep level transient spectroscopy (DLTS) method. Five electron traps and two hole traps have been observed. Deep energy levels are characterized by energy position in the bandgap, capture coefficients for majority carriers, and concentration profiles of trap densities. The possible identity of each trap is discussed with respect to data published in the literature.

The present paper reports on the results of investigation of the surrounding medium parameter control devices on the basis of magnetic bubble conducting materials.

Silicon layers deposited by low pressure chemical vapor deposition at a temperature between 520 degree(s)C and 620 degree(s)C have been oxidized at 600 degree(s)C to evaluate the feasibility of a pad oxide for a multilayered insulator used as the gate of a thin film transistor. It is concluded that such a pad oxide can be used if the silicon is deposited in the amorphous phase.

The transport properties of the pseudomorphic system Al_0.23Ga_0.77As-In_0.11Ga_0.89As have been studied by magneto-transport combined with high pressures technique up to 8 kbar at 4 K. Shubnikov-de Haas measurements reveal a marked decrease in carrier concentration with increasing pressure, which is attributed to carriers being trapped at centers responsible for parallel conduction. From Van der Pauw measurements at various temperatures and pressures, the presence of a DX-like center is proposed. At high pressures, the reduced scattering and Fermi energy allows the resolution of some spin-split levels giving an indication that the g-factor is enhanced in this system as compared to the bulk InGaAs, although a precise value is not extracted.

An advanced method was developed for MESFET burn-in purposes, based on preserving the samples in different stages of the degradation process, due to thermal and electrical stress, for subsequent structural investigations. This is performed by the automatic termination of the electrical stress separately on any device before its complete destruction. The equipment realizing this method is also described.

Four different possibilities are proposed for the fast checking of doping and impurity concentration in semiconductors. The proposition is based on the characteristic experimental concentration dependence of the breakdown voltage, the slope of the reverse I-V characteristics, the ac conductivity, and the capacitance at zero bias, obtained in planar and mesa Au/Cr/n-GaAs Schottky contacts.

A comparative investigation of flash lamp and laser doping of Si was carried out in order to study a possibility of pulsed solid-phase processing of large size wafers. Submicron boron- doped layers in Si were formed by either Xe flash lamp or CO₂ laser applications. Two types of surface dopant source were successfully used: pure boron and boron-containing emulsitone. SIMS, four-probe method, and Hall effect were used for sample characterization.

Laser recrystalization on silicon dioxide polysilicon islands by pulsed laser radiation has been carried out. As a result of laser treatment single-crystalline layers have been produced which were investigated by means of translucent electron microscopy. It has been shown that the solution obtained for temperature distribution can be expressed via elliptical Jacoby sine. The n-channel metal-dielectric-semiconductor transistors with electric parameters close to the device made on crystal substrate are prepared on the island regions by the method of planar technology.

A Q-switched ruby laser was applied for ohmic contacts formation to n-GaAs. A previously deposited composition of Au:Ge+Ni+Au was used as contact material. SIMS and V-A dependence measurements were carried out for contact characterization.

A method of impurity laser gettering applicable to complex semiconductors of the CdTe type is suggested and investigated. The methods of photoluminescence and structural analysis revealed the efficiency of laser recrystallization of a semiconductor plate non-operating area which further serves as the getter zone. The mode of laser radiation from the self-absorption area, which leads to priority evaporation of a more volatile component in the complex semiconductor, forms a stable zone of mechanical stresses which in further heat treatment serves as an efficient run-off for undesired impurities and dot defects.

We have developed a new production technology of deep trenches RIE with a photoresist mask. RIE was performed in a low-pressure batch diode reactor. Wafers were placed on RF (5,28 MHz) electrode covered by organic lacquer. The maximum loading was 24 wafers having a diameter of 100 mm. Positive photoresist with 2 micron thickness was used for masking without any thermal treatment after development. The line width was 1.5 - 2.0 micron. Because earlier investigated mixtures of chlorine and bromine-containing halocarbons with SF₆ didn't allow sufficient selectivity silicon/photoresist, we have proposed to use for deep silicon etching the mixture of CF₃I/SF₆ and investigated the dependence of silicon and photoresist etch rates and etch anisotropy on basic controlled plasma parameters.

The influence of doping the gated oxide of submicron (channel length approximately 2 micrometers ) MOSFETs with phosphorus on their characteristic degradation has been investigated. It is shown that phosphorus ion implantation into polysilicon lying on the oxide in the range of 500 - 1.500 (mu) C/cm² followed by thermal treatment at 850 degree(s)C for diffusing the phosphorus into the oxide results in a negligible threshold voltage growth and transconductance reduction. Mobility degradation in a MOSFET channel of a split drain- contact transistor has been tested by means of an in-situ Hall current method. It is shown that doping oxide with phosphorus leads to a negligible reduction of charge carrier mobility. Device degradation in electric regimes, providing injection of hot carriers into the gated oxide, has been studied. It is shown that a time dependence character of the mobility degradation of charge carriers measured by the Hall-current method differs from that calculated form the device transconductance. It is supposed that it is due to shortening the effective channel length during the formation of localized charge areas in the gated oxide near the drain. It is shown that the device characteristic degradation with P-doped gated oxide in the substrate maximum current regime at high (3.5 5V) gate voltage decreases as compared with that of undoped devices.

This work contains results of investigations on photoemission in thin oxide layers in which internal electric field has been generated. In other works, secondary electrons of energy greater than that of primary electrons have been detected. This anomalous phenomenon is also expected in the case of photoemission controlled by the internal electric field. The investigated samples were microscopic glasses covered with conducting layers (SnO₂:Sb). On one side photoemission was measured, whereas on the other side the polarizing voltage U_pol which generated the electric field in the investigated layer was applied. Amplitude distributions of impulses for samples of various thickness and at various U_pol were determined. The measurements were performed with a multichannel impulse amplitude analyzer (NTA 1024). For samples of thin emitting layers (about 10 nm) the amplitude spectra could be described with a Gaussian curve. For thicker samples (above 150 nm) and at sufficiently large negative voltage U_pol, the spectra could be described with a sum of at least two Gaussian curves. This would be evidence of receiving two or more photoelectrons from a single light quantum.

The results of the theoretical analysis of electric field structure in a spatial light modulator with viscoelastic deformable layers controlled by addressing a CMOS active matrix are presented.

A closed-form analytical expression is given for the bandwidth of p-i-n avalanche photodiodes in a normalized form. The formula simultaneously describes the effect of the time constant of the RC network formed by the load resistor and junction capacitance and the finite gain- bandwidth product of the avalanche multiplication process. An optimum choice of the depletion layer width resulting in maximum bandwidth is also given.

The various layers of InGaAsP/InP heterostructures have been grown by LPE for PIN and SAM avalanche photodiodes working near 1300 nm. The electrical and optical properties were investigated. With simple run of LPE growth, the low dark current, low capacitance PIN photodiodes have been fabricated. For SAM structure, avalanche gain of M approximately equals 12 near breakdown voltage was measured.

The processing dependent properties of PECVD SiN_xC_yH_z and BN_xH_y thin insulating films deposited using hexamethyldisilazane (HMDS) or HMDS + NH₃ mixture and borazine without and with helium dilution, respectively, were considered. The deposition temperature of the films was varied in the range of 50 - 500 degree(s)C. The results of investigations of the chemical composition, kinetics of growth, optical and electrical properties of the films are presented. The correlations between these properties and the chemical composition and growth conditions are established. It has been found that ammonia added to HMDS considerably improves the insulating properties of SiN_xC_yH_z films. We can conclude that the ionic-type instability in the MIS-structure with BN_xH_y was caused by hydrogen, incorporated into the films during growth. The conditions of stable dielectric film preparation have been determined. The films can be used as insulators for microelectronic devices on compound semiconductors.

Modeling of disilicide deposition in the system with volatile metal organic and fluorinated silicon organic compounds was performed for a number of systems: M-Si-C-H-Ar, M-Si-C-O- Cl-H-Ar, M-Si-C-H-F-Ar, and M-Si-C-O-F-H-Ar (M equals W,Mo). It was shown that in some of these systems (especially with fluorinated compounds) there are wider regions of quasi- equilibrium deposition of disilicides.

The thermal activation energy of an impurity in a semiconductor is of fundamental interest both from the point of view of applications and of basic physics. Its value, as deduced from the Hall effect data, depends on the concentration of impurity centers as well as the compensation degree. Various theoretical models have been proposed in the literature to account for this effect. Results of the Hall effect measurements on strongly compensated p- type GaSb were compared with the predictions of the available theoretical models. It was found that among the models considered, the model based on the concept of macroscopic potential fluctuations gives the best quantitative agreement with the experimental data.

Mg-doped GaAs and Al_xGa_1-xAs (x