Materials of Electronics Engineering (E-Journal) / Известия высших учебных заведений. Материалы электронной техники
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Рынок монокристаллов GaAs — тенденции развития
Get PDFA review of the current state of the GaAs market as well as the state and the prospects of the Russian market have been provided. A brief analysis of the current state of RF−devices has been given The dynamics of world GaAs production and prices for the recent years have been reported. Methods of single crystal GaAs growth and tendencies of growth technology development have been described. The market of GaAs substrates, as expected, will amount to 3.6 million sq. inches and $650 million by 2017. Despite the high financial performance of the gallium arsenide market, the physical indicators of the world single− crystal GaAs market will remain rather small compared to worldwide figures, i.e. ~ 800 t/year by 2020. At the moment, the world market of GaAs single crystals and wafers exhibits a comparatively small volume, high concentration of production capacities in China and the presence of major players capable to endure adverse conditions. Russian market of special semiconductor materials (GaAs, etc.) has a volume that is small compared to worldwide figures. However, there is an understanding that the implementation of import substitution programs and the development of advanced electronic component base in Russia require the fabrication facilities for high purity compounds and initial components. Since 2015 GaAs plate production projects have emerged under the auspices of Roselektronika
ЭФФЕКТЫ НИЗКОИНТЕНСИВНОГО ОБЛУЧЕНИЯ В ПРИБОРАХ И ИНТЕГРАЛЬНЫХ СХЕМАХ НА БАЗЕ КРЕМНИЯ
Get PDFThis paper is a review on total ionizing dose effects in silicon semiconductor devices and integrated circuits under low dose rate irradiation that is typical of space applications. We consider the mechanism of radiation induced charge buildup in the dielectric of MOS structures and at the semiconductor/dielectric interface; in addition, the paper reports an analysis of the nature of defects in Si/ SiO2 structure which are responsible for these processes. Also, the paper describes specific features of annealing of the charge trapped in dielectric and interface traps. The degradation of MOS and bipolar devices is considered for low dose rate irradiation conditions inherent to space application. We show that under low dose rate irradiation MOS devices are susceptible to time−dependent effects which are determined by the kinetics of charge buildup and annealing in the Si/SiO2 structure, while bipolar devices may be susceptible to true dose rate effects. The paper considers basic experimental modeling methods for low dose rate effects during accelerated testing of silicon devices and integrated circuits. We show that it is necessary to use essentially different experimental approaches for the modeling of time−dependent effects in MOS devices and true dose rate effects in bipolar devices and integrated circuits.Рассмотрены дозовые ионизационные эффекты в полупроводниковых приборах и интегральных схемах на базе кремния в условиях воздействия низкоинтенсивного ионизирующего излучения космического пространства. Дано описание механизма радиационно−индуцированного накопления заряда в диэлектрике МОП−структур и на границе раздела полупроводник/диэлектрик. Также проанализирована природа дефектов в структуре Si/SiO2, отвечающих за эти процессы. Преведены особенности отжига накопленного при облучении заряда в диэлектрике и поверхностных состояний. Рассмотрены особенности деградации МОП− и биполярных приборов в условиях низкоинтенсивного радиационного облучения, характерного для космического пространства. Показано, что в условиях низкоинтенсивного облучения в МОП−приборах возникают зависящие от времени эффекты, обусловленные особенностями кинетики накопления и отжига зарядов в структуре Si/SiO2, тогда как в биполярных приборах наблюдаются истинные эффекты мощности дозы. Дан обзор основных методов экспериментального моделирования эффектов низкоинтенсивного облучения при ускоренных испытаниях кремниевых приборов и микросхем. Показано, что для моделирования зависящих от времени эффектов в МОП−приборах и истинных эффектов мощности дозы в приборах и микросхемах биполярной технологии используют принципиально разные экспериментальные подходы
Оценка объектов интеллектуальной собственности в сфере наноиндустрии
Get PDFThe features of nanomaterials as objects of intellectual property (OIS) are considered. The role of the information-analytical system of the MITIS “Intellectual Property: Protection and Commercialization” in the legal protection and commercialization of the results of scientific and technical activities is shown. The methods of evaluation of intellectual property objects are considered and the comparative characteristics of OIS estimation methods are given. As the OIS of the nanoindustry, the development of a new technology for the synthesis of the FeCo/C nanocomposite was chosen. The use of FeCo/C metal-carbon nanocomposite and the substantiation of the choice of the design solution for nanocomposite production technology are considered. The feasibility study of the FeCo/C nanocomposite production project was completed and the market value of the developed technology was estimated.Рассмотрены новые разработанные наноматериалы и технологии их производства в качестве объектов интеллектуальной собственности (ОИС). Показана роль информационно-аналитической системы НИТУ «МИСиС» «Интеллектуальная собственность: охрана и коммерциализация» в правовой охране и коммерциализации результатов научно-технической деятельности». Одним из направлений деятельности НИТУ МИСиС является создание новых наноматериалов и технологий их производства. С целью коммерциализации новых наноматериалов и технологий их производства в НИТУ МИСиС разработаны предварительные технико-экономические обоснования по отдельным проектам, проведен расчет рыночной стоимости ОИС, в том числе и для постановки на баланс вуза для последующей их реализации потенциальным инвесторам. В разработке технико-экономических обоснований, расчете рыночной стоимости новых наноматериалов (как ОИС) принимают участие студенты-экономисты. Это позволяет на основе использования внутреннего потенциала вуза без дополнительного финансирования готовить технико-экономическое обоснование проектов, расчет рыночной стоимости ОИС, что представляет предметный интерес для потенциальных инвесторов. Рассмотрены преимущества и недостатки различных подходов в оценке объектов ОИС. В качестве примера ОИС в сфере наноиндустрии рассмотрена разработка новой технологии синтеза нанокомпозита FeCo/C. Проанализировано применение металл-углеродного нанокомпозита FeCo/C и обоснован выбор проектного решения по технологии его производства. Выполнено технико-экономическое обоснование проекта производства нанокомпозита FeCo/C и дана оценка рыночной стоимости разработанной технологии
СИНТЕЗ СИСТЕМЫ CASNO3 : YB3+,ER3+,НО3+ И ИССЛЕДОВАНИЕ ЕЕ ЛЮМИНЕСЦЕНТНЫХ СВОЙСТВ ПРИ ИК−ВОЗБУЖДЕНИИ
Get PDFFeatures of solid−phase synthesis and a research technique of the perovskit structure of calcium stannat activated by three ions of the rare−earth elements Yb3+, Er3+, Ho3+ are described. It is established that for the formation of luminescent structure of CaSnO3 : Yb3+, Er3+, to Ho3+ the following conditions of synthesis are required: calcination temperature 1250 °C and duration at least 18 h. the luminescent properties of the samples for excitation were probed by a semiconductor laser diode with a 960 nm wavelength. Luminescence emission bands in the visible and IR−regions were recorded. We show that Yb3+ ions preferentially act as sensitizers and are capable to transfer part of the absorbed energy to Er3+ ions and Ho3+, causing a luminescence gain in the bands corresponding to them. Er3+ ions also transfer part of the absorbed energy to Ho3+ ions, and therefore an intensity gain of IR luminescence in the bands at 1194 and 1950 nm is observed. The diagram of energetic transitions is provided for the CaSnO3 : Yb3+, Er3+, Ho3+ system for excitation by a laser with a 960 nm wavelength, and the mechanism of energy transmission between ions of Yb3+, Er3+, Ho3+ is explicitly described. The dependence of the luminescence intensity of the studied phosphor in the area 994, 1194, 1550, 1950 nm on the concentration of Ho3+ ions is studied. The intensity maxima for the emission bands at 1194 and 1950 nm are observed for Ho3+ ion concentration of 0.007 atomic shares. It is suggested to use the CaSnO3 : Yb3+, Er3+, Ho3+ luminescent structure as the source of radiation capable to transform IR radiation in the 960 nm region to IR radiation with a wavelength of about 2000 nm
Эволюция системы моделей и алгоритмов для расчетов параметров технологических процессов получения материалов микро- и наноэлектроники
Get PDFResults of developing a system of models and algorithms for parameter calculation in micro and nanoelectronics materials processes and equipment design have been considered. A distinctive feature of the teaching methods for special technological courses on electronics materials is that the courses are designed by analogy with electronics materials technologies: from a bulk single crystal to device structures the typical dimensions of which are within several tens of nanometers. A scientific model approach to the solution of technological problems has been developed during the study of heat and mass transfer processes which, along with the interaction processes in liquids and gas and with account of the heterogeneous reactions, are the theoretical basis of the electronics materials technology. The possibilities of physical and mathematical modeling have been compared. Approaches to the creation of mathematical models for the single crystals growth processes of semiconductors, epitaxial layers and heterostructures have been considered and their possible practical applications have been outlined. We show that the ideas put forward by V.V. Krapukhin at early stages of training specialists in electronics materials technology and further developed by his students have formed the basis for the training of several generations of highly skilled specialist
ИЗУЧЕНИЕ КРИСТАЛЛОВ ЧАСТИЧНО СТАБИЛИЗИРОВАННОГО ZRO2 ЛЕГИРОВАННЫХ CE МЕТОДОМ ЭЛЕКТРОННОГО ПАРАМАГНИТНОГО РЕЗОНАНСА
Get PDFThe study of crystals of ZrO2 solid solutions (PSZ) stabilized with yttrium and cerium oxides was carried out by electron paramagnetic resonance (EPR) in the X and Q range. The presence of Zr3+ centers in annealed ZrO2 crystals stabilized only by yttrium oxide (2.8 mol.% Y2O3) is established. Another kind of paramagnetic O−centers appear when CeO2 is added to ZrO2 crystals in addition to yttrium oxide. To estimate the concentration of Ce3+ ions in PZS crystals, EPR spectra were recorded in the presence of a reference specimen at 7 K. Paramagnetic Ce3+ ions have been identified and their relative amounts in PSZ crystals before and after high−temperature heat treatment has been measured. The annealing in air leads to a decrease in the concentration of Ce3+ ions for all compositions and changes the color of the crystals from red to white. After annealing in the 2.0Y0.8Ce3Zr sample, the amount of paramagnetic Ce3+ ions decreased approximately twice. Paramagnetic centers from Ce3+ are not detected in a the sample with a low cerium content of 0.1 mol.% after annealing which indicates the complete transition of Ce3+ to the Ce4+ state. It is shown that the formed paramagnetic centers of cerium are bound by strong exchange interactions. No angular dependence of the EPR lines for the paramagnetic Ce3+ cations on the applied external magnetic field was observed. The probable reason for the absence of such angular dependence is that impurity rare−earth ions are located next to each other, forming impurity clusters with effective spin Seff = 1/2
РОСТ ЭЛЕКТРИЧЕСКИХ ХАРАКТЕРИСТИК СВИНЦОВО−КИСЛОТНОГО АККУМУЛЯТОРА ПОД ВЛИЯНИЕМ МИКРОУГЛЕРОДНЫХ ДОБАВОК
Get PDFThe features and changes in the microstructure of the negative electrode material of a lead−acid battery appearing after adding of carbon black and hybrid carbon were investigated. As shown by X−ray phase analysis and scanning electron microscopy, carbon black and hybrid carbon additives influence the electrode material structure causing changes in soaking and formation processes. In accordance with the structural research, hybrid carbon increases the dispersity of the negative active material and impedes sulfate ions diffusion into its internal layers. Electrical tests of lead−acid batteries including high rate partial state of charge cycling were conducted and the roles of each kinds of carbon additives were estimated. It was shown that the addition of hybrid carbon increases the cycle life of the batteries at high rate partial state of charge operation, improving charge acceptance approximately by 9 % and deep discharge stability. Capacity loss after deep discharge is less than 4.4 % if hybrid carbon is used as an additive and 7.2 % in case of carbon black.Исследованы особенности и изменения микроструктуры электродного материала отрицательного электрода свинцово−кислотных стартерных аккумуляторных батарей, возникающие при добавлении двух различных образцов углерода: технического или гибридного. Проведен рентгенофазовый и электронно− микроскопический анализ материала электрода. Установлено, что использование технического или гибридного углерода в качестве добавки к материалу отрицательного электрода оказывает влияние на его структуру, вызывая изменения в процессах его пропитывания и формирования. На основании структурных исследований предложено качественное описание, в соответствии с которым гибридный углерод повышает дисперсность отрицательной активной массы, затрудняет диффузию сульфат−ионов. Проведены типовые испытания путем интенсивного циклирования в не полностью заряженном состоянии свинцово−кислотных стартерных батарей в режиме «заряд—разряд». Батареи изготовлены с использованием отрицательных пластин с добавками технического или гибридного углерода. Определено влияние каждого типа углеродной добавки на электрические характеристики стартерных батарей. Так, показано, что добавка гибридного углерода способствует увеличению срока службы стартерных батарей при эксплуатации в не полностью заряженном состоянии. Такая добавка повышает прием заряда в среднем на 9 % и устойчивость батареи к глубокому разряду, когда падение емкости составляет не более 4,4 %, а в случае использования технического углерода падение емкости составляет 7,2 %
О сенсорной активности углеродных нанотрубок, модифицированных карбоксильной, аминной и нитрогруппами, в отношении щелочных металлов
Get PDFThis article presents a theoretical study of sensor activity of nanosystems based on carbon nanotubes modified with functional groups (carboxyl, aminogen, nitrogroup) for some metal atoms and ions. Calculations have been performed within the frameworks of a molecular cluster model with the use of the semiempirical MNDO method and the density functional theory DFT. The mechanism of functional group binding to the open border of single−walled zig− zag carbon nanotubes leading to the formation of chemically active sensors on their basis has been investigated. Main geometric and electron energy characteristics of the resultant systems have been defined. Interaction of the sensors so synthesized with atoms and ions of some metals, e.g. potassium, sodium and lithium, has been analyzed.Обобщены результаты теоретического изучения сенсорной активности наносистем на основе углеродной нанотрубки, модифицированной функциональной группой (карбоксильной, аминной, нитрогруппой) в отношении некоторых металлических атомов и ионов, выполненного с использованием полуэмпирической расчетной схемы MNDO и теории функционала плотности DFT. Рассмотрен механизм присоединения функциональных групп к открытой границе однослойных углеродных нанотруб типа zig−zag для образования химически активного сенсорного зонда на их основе и взаимодействие построенных таким образом зондов с атомами и ионами калия, натрия, лития. Проведен сравнительный анализ активности сенсорных наносистем в отношении выбранных элементов и сделан вывод о выборе наиболее предпочтительной функциональной группы для модифицирования углеродных нанотрубок, которые могут быть использованы в качестве сенсорных зондов для идентификации атомов и ионов калия, лития и натрия, в том числе присутствующих в солях и щелочах
Анизотропия механических свойств и механизмы упрочнения в кристаллах твердых растворов ZrO2—Y2O3
Get PDFAbstract. The anisotropy of the mechanical properties of single crystal ZrO2 — 2.8 mol.% Y2O3 solid solutions has been studied. The crystals have been grown by skull melting technique. The microhardness and fracture toughness have been tested for different crystallographic planes by indentation with different indenter diagonal orientations. The study shows that the microhardness of the material depends on the crystallographic orientation but slightly whereas the fracture toughness varies for different planes. The maximum fracture toughness has been observed in the crystal specimen cut laterally to the <100> orientation. We have studied the anisotropy of the microhardness in the material for different indenter diagonal orientations. The maximum fracture toughness has been obtained for the {100} plane and the <100> indenter diagonal orientation. The phase composition inside and outside the indents on the {100}, {110} and {111} surfaces for 20, 3 and 1 N loads has been studied in local areas using Raman spectroscopy. The degree of the tetragonal−monoclinic transition has been evaluated for different crystallographic planes and different indenter diagonal orientations. The tetragonal−monoclinic transition proves to be anisotropic, and this affects the transformation hardening mechanism. The maximum amount of the monoclinic phase is present in the vicinity of the indent in the {100} plane for the <100> indenter diagonal orientation. The highest fraction toughness has also been observed in the {100} plane for the <100> indenter diagonal orientation. Probably, the abovementioned indenter diagonal orientation provides for the maximum stress concentration along the coherent conjugation planes between the tetragonal and the monoclinic phases during the tetragonal−monoclinic transition, i.e. (100)t||(100)m and [001]t||[010]m
Получение материала на основе селенида меди методами порошковой металлургии
Get PDFCopper selenide is a promising material for power generation in medium−temperature range 600—1000 K. A number of features of the Cu—Se system, i.e. the existence of a phase transition in Cu2Se compound, the high speed of Cu ion diffusion and the high vapor pressure of Se at high temperatures, necessitate massive experimental investigations aimed to develop and optimize a method for obtaining a copper selenide base bulk material. In this work the effect of mechanochemical synthesis mode and subsequent compaction method on the thermoelectric properties and structure of copper selenide were studied. The source material was obtained by mechanochemical synthesis. The hot pressing and spark plasma sintering methods were used for obtaining the bulk samples. The structure and phase composition were studied by X−ray diffraction and scanning electron microscopy. We show that increasing the time of mechanochemical synthesis to 5 hours leads to copper depletion of the powders and the formation of nonstoichiometric phase Cu1,83Se which persists after spark plasma sintering. Comparison of the structure and properties of the material obtained by spark plasma sintering and hot pressing showed that the material obtained by hot pressing has a greater degree of the grain defects. The highest thermoelectric efficiency ZT = 1.8 at 600 °C was observed in the material obtained by spark plasma sintering. We show that the main factor affecting the value of the thermoelectric efficiency ZT of the studied materials is the low thermal conductivity. The difference in thethermal conductivities of the materials obtained by different methods is attributed to the electronic component of thermal conductivity