Елементи теорії та прилади твердотілої електроніки. – 2002. – №458

Permanent URI for this collectionhttps://ena.lpnu.ua/handle/ntb/42439

Вісник Національного університету «Львівська політехніка»

У Віснику опубліковано результати науково-дослідних робіт професорсько-викладацького складу, аспірантів та докторантів електрофізичного факультету Національного університету “Львівська політехніка”, науковців та викладачів із провідних вищих закладів освіти та академічних інститутів. У Віснику публікуються роботи провідних вчених Республіки Польща та Словаччини. Тематика робіт пов’язана з питаннями теорії фізики напівпровідників та напівпровідникових приладів, теоретичними і практичними проблемами мікроелектроніки та сенсорної техніки. Для викладачів, наукових співробітників, аспірантів, інженерів, студентів.

Вісник Національного університету "Львівська політехніка" : [збірник наукових праць] / Міністерство освіти і науки України, Національний університет "Львівська політехніка. – Львів : Видавництво Національного університету «Львівська політехніка», 2002. – № 458 : Елементи теорії та прилади твердотілої електроніки / відповідальний редактор Я. С. Буджак. – 291 с. : іл.

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Now showing 1 - 20 of 54

Optical links of data transmission in city areas
(Видавництво Національного університету "Львівська політехніка", 2002) Rajba, Stanislaw; University of Bielsko-Biała, Poland
Modernly produced optical links of data transmission, which are working in an opened waether area on infrared waves, are used as links of data transmission in cities. Optolines are used for fast construction of connections on distances ranging from tens of meters to several kilometers. They are used to transmit bit rates of 2Mbit/s or n*2Mbit/s. The article presents the operational estimate of usefulness of the optoline working on waves of X = 0,86 - 0,92/im spectral range. Despite low estimates of the product a new prospect appears before it. New technologies enable optolines to work on waves of X = 9 - 12pm spectral range and are the future for evolution of that practical device. The article also speaks of expectations in the subject of transmission parameters.
Reliability improvement in consequence of investigation PCB silver electrochemical migrations
(Видавництво Національного університету "Львівська політехніка", 2002) Jordanov, Nikola Stefanov; Andonova, Anna Stoynova; Atanasova, Natasha Georgieva; Technical University of Sofia, Dept. of Microelectronics
Looking for a compromise between high functionality and convenient and effective materials the silver has got many proved and achievements qualities for PCB. The main problem in using as a constructive materials its high disposition of migration. The investigation of a concrete type of migration between silver conductors is the goal of the paper. For this purpose an investigation techniques is presented to qualifying PCB structures. Some test structures are designed and produced and experimental results are results are analyzed.
Analysis of ceramic chip capacitors at high frequency
(Видавництво Національного університету "Львівська політехніка", 2002) Golumbeanu, Virgil; Svasta, Paul; Ionescu, Ciprian; University Politehnica Bucharest, Romania
The dimensions of monolithic ceramic capacitors today becomes very small and they presents good performance at high frequency. It is used in various high frequency circuits for impedance matching, DC block, filter, bypass and decoupling functions. For the best performance in these applications , low equivalent series resistance and equivalent series inductance is required. This parameters are analyzed in the paper for multilayer ceramic chip capacitors. Using an impedance analyzer and SPICE simulations the impedance of capacitors at high frequency is presented.
Eelectrooptical devices based on the structure of planar waveguide – smectic C* - planar waveguide
(Видавництво Національного університету «Львівська політехніка», 2002) Mikityuk, Zenon; Dalanbayar, Bolormaa; Lviv Polytechnic National University; Department of Physics, Mongolian Academy of Science, Ulaanbaatar, Mongolia
Unique optical properties of chiral liquid crystals allow to use them in different electrooptical devices. It is possible to filtrate the light by length of a wave with the help of structures waveguide - liquid crystal - waveguide. Besides the electrical control of such structure enables to use the planar waveguide – smectic C* - planar waveguide structure as the switch without the complex constructive solutions.
The self-coordinated computation of electronic power spectrum and wave function in crystals with type structure to diamond
(Видавництво Національного університету "Львівська політехніка", 2002) Sobchuk, Igor; Rakobovchuk, Larisa; Мischyshyn, Volodymir; Lviv Politechnic National University
The calculations of self-coordinated power spectrum in the basic high symmetrical зБ ГL and ГХ directions are stated in this article. Because the germanium has a lesser width of forbidden zone in comparison by silicon, that approximates it to metals, then influence of correlation effects becomes prettily perceptible. That's why attached to Е(к) calculations of germanium the correlation amendments are included into crystalline potential. The analysis of results calculations shows, that an increasing of base length to 331 ПХ brings to energy values stabilization, which are close to experimental.
Compression of signals obtained from the fibre-optic flame monitoring system
(Видавництво Національного університету "Львівська політехніка", 2002) Wójcik, Waldemar; Kotyra, Andrzej; Golec, Tomasz; Duk, Mariusz; Technical University of Lublin, Polan; Institute of Power Industry, Poland
In the article, we present application of wavelet transform and Fourier transform in compressing signals obtained from the flame monitoring system. The results of compression are compared by function of relative error vs. compresion ratio.
On-line subtraction method for mains interference from ECG signals with signal processor
(Видавництво Національного університету "Львівська політехніка", 2002) Georgieva, Tsveta Simeonova; Mihov, Georgy Slavchev; Technical University – Sofia, Bulgaria
In this article we described the subtraction method for removing mains interference from ECG signals and realized its algorithm in real time by digital signal processor. Tree filtering procedures included in our algorithm are organized as separate modules, which permit us to apply various types of filters without changing the main structure of the algorithm. This organization is very useful and gives us a possibility to analysis and optimization of the subtraction method.
Multipurpose solid-state integrated circuits for sensor transfer characteristic formation
(Видавництво Національного університету "Львівська політехніка", 2002) Holyaka, Roman; Hladun, Michael; Lviv Polytechnic National University
The design philosophy and elaboration results for multipurpose solid-state integrated circuits for sensor transfer characteristic formation are considered in the paper. The circuits for linearization and thermocompensation of transfer function and for multiplication of temperature coefficient are presented. Elaborated integrated circuits are characterized by simplicity and operation with low-voltage unipolar supply sources and they allow to improve precision and widen functional applications of new generation sensor devices.
High ohmic measurements of thick film glass layer insulators
(Видавництво Національного університету "Львівська політехніка", 2002) Jakubowska, Małgorzata; Grzesiak, Wojciech; Institute of Electronic Materials Technology, Poland; Institute of Electron Technology, Poland
Low-current contacts analysis with the application of mathematical-physical models
(Видавництво Національного університету "Львівська політехніка", 2002) Zlonkiewicz, Zbigniew; Technical University of Lublin, Institute of Fundamental Electrical Engineering and Electrotechnology, Poland
The paper presents the results of modelling of contacts used in low current circuits. Mathematical and physical models are useful in the analysis of such contacts to describe the complex real shape of contact areas. FLUX 2D packages have been used for simulations assuming contact model in the form of an ellipse. The selected contacts are covered with a hard golden layer on a PdNi20 beneath layer. The distribution of current intensity, power and voltage in the contact areas has been determined.
Selection of wavelengths for optoelectronic CO and O2 concentration analyser
(Видавництво Національного університету "Львівська політехніка", 2002) Wójcik, W.; Manak, I.; Kotyra, A.; Smolarz, A.; Golec, T.; Kalita, M.; Komada, P.; Technical University of Lublin, Poland; Belarusian State University, Belorus; 3 Institute of Power Industry, Poland
Measurement of CO and O2 concentration near walls of a power burner allows limiting adverse side effects of the low-emission combustion. Conditions in which the measurements have to be made restrain the selection of wavelength used in absorption spectroscopy method. The article describes the absorption spectroscopy basics as well as the restrains that have to be considered when selecting the wavelengths.
Dynamic properties of humidity sensor with active layer based on composite material: PVA + Sn
(Видавництво Національного університету "Львівська політехніка", 2002) Hotra, Zenon; Proszak, Danuta; Melnyk, Oleg; Woś, Bogdan; Lviv Polytechnic National University; Rzeszów University of Technology, Dept. of Electronic and Communication Systems; Rzeszów University of Technology, Department of Heating and Climatization; Rzeszów University of Technology, Department of Physics
This paper presents results of the researches upon humidity sensors based on humidity sensitive composite material: PVA + Sn. Construction of the sensor is presented. Influence of electrodes’ configuration and arrangement on static characteristics and dynamic properties of the sensors are also included.
The reflections produced by lumped load of digital signal line
(Видавництво Національного університету "Львівська політехніка", 2002) Golumbeanu, Virgil; Svasta, Paul; Ionescu, Ciprian; University Politehnica Bucharest
In interconnection technique of digital circuits in general the matched lines method for reducing the influence of reflections in a view to a good working of interconnected circuits is used. Due to the input capacitance of digital circuits appears a reactance load. Although the matching is very good realized from the viewpoint of the resistive load, there is a reactive mismatching that can produce reflections at high frequency. Using Laplace transformation the reflections produced by parasitic capacitance load will be determined. These reflections will be analyzed depending on the type of the digital circuits and the parameters of the interconnection line. For some types of digital circuits the maximum fanout from this point of view will be determined.
Module for fuel consumption measurement
(Видавництво Національного університету «Львівська політехніка», 2002) Drumea, Petrin; Comes, Mircea; Mirea, Adrian; Hydraulic and Pneumatic Research Institute, Romania
Today is important for transport companies to monitorize fuel consumption. To perform this task is necessary to have on the car a black box inaccessible to driver. This can be done using a flow transducer coupled to a smart electronic module. The authors designed a volumetric rotational transducer that contains a Hall sensor. The pulses generated by this sensor as well as driving wheels rotation information are used by an electronic module to calculate total fuel consumption.
Selected problems of one-chip microcomputers’ applications in DC/AC converting circuits
(Видавництво Національного університету "Львівська політехніка", 2002) Grzesiak, Wojciech; Maj, Tomasz; Cież, Michał; Zaraska, Wiesław; Kalita, Włodzimierz; Sabat, Wiesław; Institute of Electron Technology, Poland; Department of Electronic Systems, Rzeszow University of Technology, Poland
The paper presents problems connected with generation of sin – and trapezoidal signals as basic ones in the DC/AC energy conversion process. Questions on loads of various characters while alimented with sine – and trapezoidal voltages have been outlined. Basic construction features of both types microcomputer equipped inverters have been discussed, in particular those dealing with a significant number of safety measures and with characteristic attributes of final power stages, determining the behaviour of inverters in various output power conditions. On examined sample inverter types of own design a complete compliance with requirements of electromagnetic compatibility standards has been pointed out thanks to proper planning and structural solutions.
The synthesis of mathematical model for magnetotransistor using PSPICE software
(Видавництво Національного університету "Львівська політехніка", 2002) Holyaka, Roman; Hladun, Michael; Humenyuk, Iryna; Sopilnyk, Lyubomyr; Lviv Polytechnic National University; National Institute of Applied Science in Toulouse, France
We present the methods for synthesis of magnetotransistor mathematical model based on dual-collector structure of lateral transistor using PSPICE software. The complexity of magnetotransistor model is caused by special effects which concern these transistors. We considered main special effects such as parasitic carrier extraction from epitaxial layer into substrate and dependence of magnetotransistor parameters on base accelerating field.
Mechatronic positioning system with the velocity control
(Видавництво Національного університету "Львівська політехніка", 2002) Drumea, Petrin; Comes, Mircea; Mirea, Adrian; Dobrin, Dănică; Hydraulic and Pneumatic Research Institute, Bucharest, Romania
This paper presents a mechatronic system for speed control in non-ferrous continuos foundry machine. This system uses a hydraulic cylinder with inductive displacement transducer, a proportional valve and an electronic module. The moving control uses a positioning closed loop. The electronic block assures position and velocity control and the stop time, too. The cylinder’s displacement is cyclical due an automatic programmer that commands the fastening cylinder, too. User can program both directions’ speed, stroke and pause time. A smooth starting move is assured by acceleration control. The electronic control module is placed in case of proportional element. The program unit contains 8 multi-turn potentiometers for setting motions program, start/stop switch and light Indicator of moving status.
Mobile micromachine
(Видавництво Національного університету "Львівська політехніка", 2002) Dovica, Miroslav; Slosarčik, Stanislav; Magyar, Miroslav; University of Technology, Košice, Slovak Republic
This article describes design of in-pipe micromachine, which is able to self motion in the thin pipe (20,3~22,3mm inner diameter). This micromachine for moving utilises of shape memory alloy (SMA) actuator. On the base of analysis in-pipe motion modes, the motion principle in-pipe micromachine based on difference friction force between contact elements of micromachine and inner pipe wall has been chosen It also explains mobile sequence, design of micromachine contact elements and experiment of friction coefficient.
Concentration dependence of Curie temperature of two-sort temperature of amorphous magnets
(Видавництво Національного університету "Львівська політехніка", 2002) Margolych, Iryna; Lviv State Medical University named after Danylo Galytsky
The Curie temperature of two-component amorphous ferromagnet is found using the expansion of the free energy in powers of order parameter. For the model with liquidtype disorder introduced via hard spheres structure factor the explicit expression for the concentration dependence of ferromagnetic ordering temperature is obtained.
Design of photoelectric convertors on the basis of Si-Ge solid solutions
(Видавництво Національного університету "Львівська політехніка", 2002) Druzhinin, Anatolij; Ostrovskii, Igor; Liakh, Natalia; Lviv Polytechnic National University
Electric and photoelectric properties of Si1-xGex (x=0.1) whiskers were investigated. The whiskers were grown by method of chemical transport reactions in closed Si-Ge-Au-Hf-Br system. Concentration of Hf in whiskers is 1,6⋅10-2 3, concentration of Au is 10-3 3. The samples have n-type conductivity; their resistivity ρ changes from 0.5 to 12 Ω⋅cm depending on the whisker diameter. The whisker diameters change from 10 to 80 µm, the whisker length is equal to 0,5÷5 mm. The whiskers were shown to be photosensitive both in photovoltaic and in photoresistive regimes. Photo-e.m.f. value is about 100 mV in the whisker with small diameter (d=20 µm) and it decreases at a rise of the whisker diameters from 20 to 80 µm. Appearance of photo-e.m.f. is caused by existance of Shotki barrier in SiGe-Pt contact to the whiskers. Dimensional effect of the whisker photo-e.m.f. is explained by the dimensional dependence of the whisker resistivity. High values of photo-e.m.f. for Si-Ge whiskers allow their using for photoconvertor design.