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Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/35393
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Документ A study of initial stages for formation of carbon condensates on copper(PC тесhnology сеntеr, 2018) Dai, Yu.; Kolupaev, I. N.; Sоbоl, O. V.In the CVD method, samples of carbon condensates were obtained under special conditions (low substrate temperature and short growth times). The use of special technological conditions makes it possible to study the initial stages of growth of graphene layers. To analyze the influence of the microinhomogeneities of the copper substrate on growth conditions, various modes of its electrochemical polishing were used in the study. The structural state of the surface was studied using computer processing of digital images of a surface with color segmentation. A metallographic analysis of more than 70 samples was carried out and three main structural elements of the initial stage of growth of graphene layers were identified on the basis of computer image processing during condensation. These are graphene layers, sections of a copper substrate and a cluster of atoms with a structural state different from the graphene (presumably amorphous). It has been established that preparation of the substrate surface should be attributed to the most important technological operations for obtaining a high-quality graphene coating. It has been found that the use of multicomponent electrolytes during the polishing of the copper substrate makes it possible to increase the uniformity in the dimensions of the structural elements of the surface roughness. This leads to an increase in the surface area of the formation of graphene layers already during the initial stages of growth (at a relatively low process temperature of 700 °C). The obtained results testify to the prospects of using multistage image analysis (using the clustering method) to optimize the technological regimes for obtaining the “carbon condensate/substrate” systems, taking into account the initial roughness of the latter.Документ Polygraphene Coatings on Copper: Mechanisms of Nucleation and Growth(Sumy State University, 2018) Kolupaev, I. N.; Murakhovski, A. V.; Koltsova, T. S.; Sobol, V. O.; Dai, Yu.Samples of polygraphene layers on a copper substrate were obtained using CVD technology. For the preparation, a gaseous mixture of methane, hydrogen and argon was used. To analyze the degree of filling and the specific area of the polygraphene formed on a copper substrate, we used optical microscopy (with specialized computer image processing) in combination with Raman spectroscopy and atomic force microscopy. It is proposed to use the approach based on the double structure model (transparent regions of graphene and copper) for evaluating the morphological parameters of the coating of polygraphene on a copper substrate. This approach is used for the primary optimization of the production process of polygraphene formation. The mechanism of initial stages of polygraphene growth on copper is proposed.Документ Экспресс метод анализа морфологических параметров графеновых покрытий на медной подложке(Сумской государственный университет, 2016) Соболь, Олег Валентинович; Колупаев, Игорь Николаевич; Мураховский, Александр Владимирович; Левицкий, В. С.; Кольцова, Т. С.; Козлова, М. В.; Ларионова, Татьяна Юрьевна; Соболь, В. О.Для получения слоев графена на медной подложке использована CVD технология в газовой смеси метана, водорода и аргона. Наряду с традиционными методами исследования морфологии роста, такими как спектроскопия комбинационного рассеяния света и атомно-силовая микроскопия, в работе для экспресс оценки степени заполнения и удельной площади областей графена использовался метод многопороговых сечений с 3-х мерным представление изображения оптической микроскопии, где в качестве третей оси Z используется шкала интенсивности. На основе полученных результатов сделаны выводы о закономерностях формирования графеновых слоев. Выявлено наличие наиболее вероятных площадей формирования графеновых доменов (~ 13 мкм²) при небольшом времени (10-20 минут) процесса получения. Увеличение времени процесса до 30 минут сопровождается повышением однородности распределения площадей формируемых доменов графена в диапазоне до 200 мкм² при высокой их фрактальной размерности в диапазоне значений HD 1,82 ... 2 0.