Видання зареєстровані авторами шляхом самоархівування
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Item Luminescence study of II-VI-based thin films deposited by close-spaced vacuum sublimation technique(Nova Science, 2019) Іващенко, Максим Миколайович; Иващенко, Максим Николаевич; Ivashchenko, Maksym Mykolaiovych; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Гнатенко, Юрій Павлович; Гнатенко, Юрий Павлович; Hnatenko, Yurii Pavlovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii SerhiiovychCdSe, Cd1-xZnxTe ternary compound, CdS:Dy rare-earth element doped II-VI compound) at different substrate temperatures is performed. In all cases of studied samples they are deposited onto non-oriented substrates using the close-spaced vacuum sublimation technique (CSVS) which makes a possibility to obtain films with optimal crystalline and optical quality. The study of the PL spectra of the investigated films makes it possible to determine their optimal growth conditions in order to obtain the films of good optical quality. The obtained results are in good agreement with the structural investigations, which we have carried out earlier using the X-ray diffraction technique. In all cases of investigated samples on PL-spectra there were observed lines that correspond to the residual impurities, which are typical for II-VI compounds (Li, Na, Cu, P). Moreover there were observed an additional lines which may be caused by the presence of point defects in crystalline structure, donor- acceptor pairs recombination processes, phonon replicas, etc.Item Quality improvement of CZTS thin films deposited by spray pyrolysis method using pulsed Nd: YAG laser irradiation(Elsevier, 2019) Шамардін, Артем Володимирович; Шамардин, Артем Владимирович; Shamardin, Artem Volodymyrovych; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Grace, O.; Kaupuzs, J.; Medvids, A.; Vecstaudza, J.In this work, thin films of Cu2ZnSnS4 (CZTS) were grown by spray-pyrolysis method and were irradiated by pulsed Nd: YAG laser. Their morphological, chemical, structural and substructural characteristics were investigated using AFM, SEM, EDS, XRD and Raman spectroscopy. Upon laser irradiation, improvement of crystallinity, stoichiometry and surface morphology were observed in the obtained CZTS thin films with the normal distribution of newly-formed particles throughout the plane. It was shown that the laser processing by pulsed Nd: YAG laser is an alternative method to the traditional post-growth thermal annealing and can be used not only for local annealing but also for annealing in various depths in the films.Item Effect of deposition temperature on the growth mechanism of chemically prepared CZTGeS thin films(John Wiley & Sons, Ltd., 2019) Шамардін, Антон Володимирович; Шамардин, Антон Владимирович; Shamardin, Anton Vladimirovych; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Medvids, ArtursThe Cu2ZnSnGeS4 (CZTGeS) thin films were deposited by the spray pyrolysis method at different substrate temperatures without further sulfurization. The influence of various deposition temperatures on the surface morphology, microstructure, optical properties, chemical, and phase composition were investigated. The substitution mechanism of Sn/Ge in the crystal lattice of CZTGeS depending on deposition temperatures was studied. It was shown that a variation in substrate temperature has a strong effect on the surface morphology of the films. The X‐ray diffractometer (XRD), transmission electron microscope (TEM), and Raman spectroscopy (RS) analysis showed that CZTGeS films were polycrystalline with a kesterite‐type single‐phase structure and a preferential orientation of (112). The RS‐mapping analysis showed the distribution of intensities on the surfaces of the films. Optical measurements showed that CZTGeS films are highly absorbing in the visible region, and the optical band gap is shifted from 1.89 to 1.84 eV.Item Determination of fundamental optical constant of Zn2SnO4 films(V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, 2017) Салогуб, Анна Олександрівна; Салогуб, Анна Александровна; Salohub, Anna Oleksandrivna; Возний, Андрій Андрійович; Возный, Андрей Андреевич; Voznyi, Andrii Andriiovych; Климов, Олексій Володимирович; Климов, Алексей Владимирович; Klymov, Oleksii Volodymyrovych; Safryuk, N.V.; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii SerhiiovychExamined in this paper have been optical properties of polycrystalline films Zn2SnO4 deposited using the spray pyrolysis method within the range of substrate temperatures 250 °C to 450 °C in increments of 50 °C. The spectral dependences have been found for the following physical quantities: k(λ), n(λ), ε1(λ), ε2(λ) and defined as they change under the influence of substrate temperature Тs. Moreover, using the model by Wemple–DiDomenico it was calculated the dispersion energy Ео and Ed for this oxide. Two independent methods defined band gaps Zn2SnO4, which decreases from 4.21…4.22 eV down to 4.04…4.05 eV with increasing Тs from 250 °C up to 450 °C.Item The optimization of functional layers of solar cells based on n-ZnMgO / p-CuO and n-ZnMgO / p-Cu2O heterojunctions(2017) Д`яченко, Олексій Вікторович; Дьяченко, Алексей Викторович; Diachenko, Oleksii Viktorovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii Serhiiovych; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Доброжан, Олександр Анатолійович; Доброжан, Александр Анатольевич; Dobrozhan, Oleksandr Anatoliiovych; Гриненко, Віталій Вікторович; Гриненко, Виталий Викторович; Hrynenko, Vitalii ViktorovychIn this paper, we present the results of the calculations of optical losses in the solar cell layers based on n-ZnMgO / p-CuO(p-Cu2O) heterojunctions with AZO and ITO front contacts. The calculations were carried out considering of light absorption in the auxiliary layers of the device. Thus, the spectral dependencies of transmittance in the absorber layer of solar cell were defined. It is made possible to optimize the design of the solar cells based on such heterojunctionsItem Опромінення за допомогою ND: YAG лазеру тонкої спрейпіролізної плівки CZTS для заліковування структурних дефектів(Сумський державний університет, 2017) Шамардін, А.В.; Істратов, М.Є.; Рекунов, Є.М.; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii SerhiiovychТонкі плівки CZTS розпиляли на підігріту до T = 623 K скляну підкладку методом пульсуючого спрей-піролізу. Товщина плівки становила 1,1 мкм. Після цього зразок опромінювали в атмосфері повітря за допомогою Nd:YAG лазера з використанням другої гармоніки λ = 532 нм з інтенсивністю I = 17,5 МВт/см2 в скануючому режимі. Для вивчення фазового складу до і після лазерного відпалу використовували метод рентгенівських дифракцій і спектроскопію комбінаційного розсіювання світла. Після опромінення на спектрах комбінаційного розсіювання світла і рентгенограмах спостерігалось зменшення напівширини піків і збільшення їх інтенсивності, що говорить про покращення кристалічної якості матеріалу.Item The performance optimization of thin-film solar converters based on n-ZnMgO / p-CuO heterojunctions(Jadavpur University, 2017) Д`яченко, Олексій Вікторович; Дьяченко, Алексей Викторович; Diachenko, Oleksii Viktorovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii Serhiiovych; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Patel, P.B.; Panchal, C.J.; Priya, Suryavanshi; Kheraj, V.A.In this paper, we present the results of the calculations of optical losses in the solar cells layers based on heterojunction n-ZnMgO / p-CuO with ZnO and ITO frontal contacts. The calculations were carried out taking into account a light absorption in the auxiliary layers of the device. As a result, the spectral dependencies of transmittance Т() in the absorber layer of solar cell were defined. It is made possible to optimize the design of the solar cells based on such heterojunctions.Item Thermoelectric properties of the colloidal Bi2S3-based nanocomposites(Jadavpur University, 2017) Доброжан, Олександр Анатолійович; Доброжан, Александр Анатольевич; Dobrozhan, Oleksandr Anatoliiovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii Serhiiovych; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Panchal, C.J.; Suryavanshi, P.; Trivedi, U.B.; Kheraj, V.A.In this work we present the proof of the concept of the novel strategy to improve the thermoelectric properties of Bi2S3based nanostructured bulk materials by blending the metallic nanoinclustions with the semiconductor nanoparticles forming the nanocomposites (NCts). The obtained NCts were composed of Bi2S3nanorods (length - 100 nm and width – 10 nm) and Ag nanoparticles (diameter - 2- 3 nm) synthesized by colloidal method. The morpohology, phase and chemical composition, electrical conductivity and Seebeck coefficient of NCts were investigated by using transmission electron microscopy (TEM), X-ray diffraction, energy dispersive X-ray analysis (EDAX), 4-point probes method and static dc-method. This strategy is the perspective way to improve the conversion efficiency of others thermoelectric materials.Item Substructural Properties and Anisotropic Peak Broadening in Zn(1-x)MnxTe Films Determined by a Combined Methodology Based on SEM, HRTEM, XRD, and HRXRD(Springer, 2016) Martinez-Tomas, С.; Климов, Олексій Володимирович; Климов, Алексей Владимирович; Klymov, Oleksii Volodymyrovych; Agouram, S.; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii Serhiiovych; Muñoz-Sanjosé, V.Lattice deformation and extended defects such as grain boundaries and dislocations affect the crystalline quality of films and can dramatically change material’s properties. In particular, magnetic and optoelectronic properties depend strongly on these structural and substructural characteristics. In this paper, a combined methodology based on SEM, HRTEM, XRD, and HRXRD measurements is used to determine and assess the structural and substructural characteristics of films. This combined methodology has been applied to Zn1-xMnxTe films grown on glass substrates by close-spaced vacuum sublimation. Nevertheless the methodology can be applied to a wide variety of materials and could become a useful characterization method which would be particularly valuable in semiconductor growth field. The knowledge of the structural and substructural characteristics can allow not only the optimization of growth parameters, but also the selection of specific samples having the desired characteristics (crystallite size, minimum dislocation content, etc.) for high-quality technological devices.Item Surface Morphology, Structural and Optical Properties of MgO Films Obtained by Spray Pyrolysis Technique(Acta Physica Polonica A, 2016) Д`яченко, Олексій Вікторович; Дьяченко, Алексей Викторович; Diachenko, Oleksii Viktorovych; Опанасюк, Анатолій Сергійович; Опанасюк, Анатолий Сергеевич; Opanasiuk, Anatolii Serhiiovych; Курбатов, Денис Ігорович; Курбатов, Денис Игоревич; Kurbatov, Denys Ihorovych; Опанасюк, Надія Миколаївна; Опанасюк, Надежда Николаевна; Opanasiuk, Nadiia Mykolaivna; Kononov, O.K.; Cheong, H.; Nam, D.X-ray diffraction, atomic force microscopy, field emission scanning electron microscopy, UV-visible photometry, and photoluminescence measurements were used to investigate the surface morphology and structural and optical properties of MgO films. Magnesium oxide films deposited by the spray pyrolysis technique were studied. The substrate temperature was varied from Ts = 643 K to 693 K. Magnesium chloride hexahydrate (MgCl2 .6H2O), dissolved in deionized water, was used as the precursor solution. It was established that the single phase films crystallize into a cubic structure with very fine crystallite size (about 2 nm). The optical band gaps of the samples were varied from 3.64 eV to 3.70 eV. Also, the films have a high level of transmittance of 90%. Photoluminescence spectra show the emission peaks at approximately 412 nm (3.00 eV) and 524 nm (2.38 eV). The peak with the energy of 3.00 eV is ascribed to holes trapped in magnesium ion vacancies acting as acceptors (F+ center). The broad emission peak at 524 nm is related to the presence of defects (F- centers) associated with oxygen ion vacancies.