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Analyse of photovoltaic solar cells by the photoluminescence method
Baura, Tomáš ; Bača, Petr (referee) ; Vaněk, Jiří (advisor)
This thesis deals with the analysis of solar cells by photoluminescence method. Photoluminescence method is based on the excitation of luminescence radiation of the solar cell material by an external excitation light source. This method can detect various types of defects in the material solar cells. The main objective is the design and realization of a measuring system defects of solar cells, which is based on this method. For excitation of luminescence is used LED array. For the detection of luminescence is used CCD camera with IR optical filter. To filter out the excitation light radiation is used disc screen and optical interrupter. The parameters and options of this measuring system are verified and characterized by test measuring for example the achievable rotation speed of screen and response of optical interrupter. At the end is tested detection of luminescence radiation of solar cells in the measuring system. The measured images are compared with the method of electroluminescence.
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The photoluminescence properties measurement of ultrathin films
Metelka, Ondřej ; Mach, Jindřich (referee) ; Šamořil, Tomáš (advisor)
The thesis briefly describes the principles and types of luminescence. In the first following research of study is also discussed the equipment which is applicable to photoluminescence experiments, including the arrangement. The second research focuses on the influence of the properties of gallium nitride (GaN) (ultra) thin films and other structures prepared by various ways on shape of photoluminescence spectra. The paperwork also describes the further optimization of photoluminescent apparatus used for the measurement of photoluminescence spectrum in the UV light radiation which is located at the Institute of Physical Engineering at the Technical University. The extension of measurements at low temperatures (design and construction of its own cryostat) is added. The conclusion concernes the test measurements to determine the effect of various settings of the apparatus on the resulting measured photoluminescence spectrum.
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Inovation of measurement equipment used for analyzing of photovoltaick cells
Otépka, Jakub ; Bača, Petr (referee) ; Vaněk, Jiří (advisor)
This bachelor thesis deals with the design of a tachometer which is used to measure and display of mechanical aperture speed of a measuring equipment for the defect analysis of solar cells using the photoluminescence method. This work is divided into three parts. The first section describes the principle of solar cells, the principle of luminescence radiation and its types. Next the defects of solar cells are analyzed. The second part discusses the theory of tachometers, the principles and methods of loading pulses. The third part is then analyzed the design and construction of the selected type tachometer.
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Plasmon enhanced photoluminescence
Édes, Zoltán ; Kůsová,, Kateřina (referee) ; Šikola, Tomáš (advisor)
Diplomová práce se zabývá fotoluminiscencí polovodičových materiálů zesílené plazmonovými polaritony. Je popsána základní teorie interakce mezi lokalizovanými povrchovými plazmonovými polaritony a fotoluminiscenčními látkami. Dva mechanismy, které mohou vést k fotoluminiscenci zesílené plazmonovými polaritony jsou diskutovány. Následně je popsán návrh aparatury pro měření fotoluminiscence a způsob její realizace. Funkčnost aparatury je ověřena měřením fotoluminiscenčních spekter objemového GaN, nanokrystalického Si a CdTe kvantových teček. Nakonec je zkoumána metoda přípravy vzorků sestávajících z kovových nanokuliček a fotoluminiscenčně aktívních CdTe kvantových teček.
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Photoluminiscence study of thin layers of MoS2
Kuba, Jakub ; Kunc,, Jan (referee) ; Bartoš, Miroslav (advisor)
The thesis deals with study of thin layers of transition metal dichalcogenides, especially of molybdenum disulfide. Nanostructures were fabricated on two-dimensional crystals of MoS2 and WSe2. Within followed analysis attention was paid to the photoluminescence properties. In the thesis transition metal dichalcogenides are reviewed and description of the modified process of preparation by micromechanical exfoliation is given.
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Analyse of photovoltaic solar cells by the photoluminescence method
Richter, Vladimír ; Bača, Petr (referee) ; Vaněk, Jiří (advisor)
This diploma thesis deals with the issues of photovoltaic cells. The main aim of this thesis is to introduce the principles of operation of solar cells and methods of detection of defects affecting their quality. The first part is about the functional properties of silicon cells and it also examines the possibilities of detecting the defects of these structures. It also describes the most commonly used modern diagnostic methods. In the next part, practical tests of photovoltaic cells using the methods electroluminescence and photoluminescence are performed. These methods are based on the excitation of luminescence radiation of the silicon material by the external light source.
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Diagnostic method of solar cells operating at very low temperatures
Bartoň, Jiří ; Stojan, Radek (referee) ; Veselý, Aleš (advisor)
This work deals with the modern diagnostic methods of defects detection of solar cells. Defects are detected by electroluminescence and photoluminescence methods. The main focus of this work is an innovation workplace for measuring solar cell defects at very low temperatures using photoluminescence. Liquid nitrogen is used to cooling solar cells. By using low temperatures can be detection methods to obtain more objektive results of diagnostic defects.
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Automatization of experimental setup for optical spectroscopy
Čecháček, Jan ; Nováček, Zdeněk (referee) ; Dvořák, Petr (advisor)
This bachelor thesis deals with the modernization and improvement of an application that automates measurements on an experimental setup for spectral and topographic mapping using confocal microscopy and near-field microscopy. The arrangement of the report, the principle of communication of the program with individual parts of the report and the principle of data collection and processing are described here. The output of the program are point spectra and 2D maps describing the topography, intensity and position of the spectral peaks. The thesis includes a research study of optical and time-resolving optical spectroscopy and their applications in nanophotonics. The correct functionality of the program is demonstrated by the results of measurements of perovskite MAPbI3 and organic substrate.
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Optical characterization of perovskite via time-resolved spectroscopy
Schlor, Michal ; Kejík, Lukáš (referee) ; Dvořák, Petr (advisor)
This bachelor’s thesis deals with experimental optical characterization of modern organic-anorganic perovskites, which are promised to improve the technology of photovoltaic cells for solar panels soon. Photovoltaic cells based upon these materials bring not only higher efficiency of solar panels, but also relatively simple and cheap manufacture. The first part of this thesis consists of basic structural qualities of perovskites as well as an overview of spectroscopic methods used to examine the properties of perovskites, especially their strong narrow–band photoluminiscence. The second part consists of characterizations of MAPbBr3, FAPbBr3 and MAPbI3 samples based on their photoluminiscence properties.
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The equipment for control very low temperatures during the detection defects of solar cells
Stojan, Radek ; Bača, Petr (referee) ; Vaněk, Jiří (advisor)
This work deals with measuring of very low temperatures during the detection defects of solar cells by photoluminescence method. Liquid nitrogen is used to cooling solar cells. Properties of liquid nitrogen and safety of handling are described in this work. Themperature in cryo area is measured by the thermocouple senzors. A main part of this work was to concept and creation of equipment for themperature controling in cryo technique. This equipment signalling danger scorch in low temperatures. The device was created to complement work place for the detection defects of solar cells by photoluminescence method.
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