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Preparation of sample cross-sections and analysis by SIMS
Karlovský, Juraj ; Pechal, Radim (referee) ; Bábor, Petr (advisor)
This thesis studies possible methods of semiconductor sample measurement by SIMS, with emphasis on testing different measurement parameters and sample preparation. Part of this master thesis deals with the design of a modified sample holder compatible with the used ToF-SIMS$^{5}$ instrument, IONTOF company, which is capable of tilting the sample by defined angle. This holder enables sample preparation in the main chamber of the instrument without the need of transferring the sample between instruments, which limits the probability of sample contamination. This sample holder was tested by ion machining of TIGBT sample edge and by imaging of a crater edge, created in previous measurement. Edge termination structures prepared by different techniques were measured on the TIGBT samples. Further measurements with the goal of optimizing the depth resolution for thin layers were done on Molybdenum-Silicon-multilayer X-Ray Mirror. Part of the measurements was focused on comparing depth profiles measured at low temperatures. For these measurements the samples with Indium multilayers in GaN substrate were used.
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Preparation and characterisation of ceramic electroactive materials for Na-ion batteries
Vaněk, Martin ; Libich, Jiří (referee) ; Čech, Ondřej (advisor)
Hlavním cílem této práce je charakterizace vzorků titanátů, jako materiálů pro sodíko-iontové (Na-ion) akumulátory. Syntéza některých vzorků je součástí této práce. Charakterizace je zaměřena na elektrochemické vlastnosti, složení a morfologii použitých materiálů. První část se zabývá lithium-iontovými (Li-ion) akumulátory. Byly vybrány, protože jsou ve vědeckých článcích dobře popsány a základní funkční princip je aplikovatelný také na Na-ion akumulátory. Materiály používáné pro katody, anody a elektrolyty následují po krátké části shrnující parametry a konstrukci Li-ion akumulátorů. Následující kapitola je zaměřena na sodíko-iontové akumulátory. Srovnání sodíku a lithia je následováno materiály používanými pro elektrody a elektrolyty (s důrazem na anodové materiály). Třetí část popisuje analytické metody použité pro charakterizaci elektrod a materiálů. Jedná se o elektrochemickou charakterizaci (cyklická voltametrie a galvanostatické cyklování s potenciálovým omezením), morfologii (rastrovací elektronová mikroskopie) a složení (X-ray difrakční spektroskopie). Poslední dvě kapitoly obsahují syntézu a charakterizaci sodného titanátu a charakterizaci dvou vzorků TiO2. Výsledky této práce jsou shrnuty v závěru.
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Air ion measurement
Lazorka, Martin ; Roubal, Zdeněk (referee) ; Špinka, Jiří (advisor)
This thesis focuses on the basic problems of ions and the ionization itself, what influence ions have to the organism. Further it examines compensation of small negative ions in the residential environment. Introduction to measurement of ion concentrations. First measurements with the aspiration capacitor which is now the most commonly used measurement of ion fields. Measurement is focused on the concentration of air ions in the building, VUT FEKT T-10, then the concentration changes depending on the daily cycle, ventilation and concentration before teaching and after teaching.
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Design of a new ion counter for the nature environment
Roubal, Šimon ; Szabó, Zoltán (referee) ; Roubal, Zdeněk (advisor)
Subject of this bachelors thesis is an realization of new control board for iontmeter that is developed at UTEE. Iontmeter must be capable of fully autonomous measure in outside contitions. That means it has to be able to run on batery for a long time and has to be to resist outside weather conditions. Measured data will be saved on an SD card and also sent using GSM network to the IoT server.
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Electrode Active Materials for Lithium-Ion Accumulators
Čech, Ondřej ; Oriňáková, Renáta (referee) ; Paidar,, Martin (referee) ; Sedlaříková, Marie (advisor)
This doctoral thesis deals with synthesis and characterisation of electroactive electrode materials for li-ion batteries and accumulators. The work is divided into two main parts. One deals with LiFePO4 based cathode composite electroactive material and in the second is described the synthesis and utilization of monoclinic TiO2(B) as an anode for li-ion cell. The main aim of the work is to relate the synthesis procedure and structural properties of both materials to its electrochemical preformance.
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Minimizing errors in measuring ultra low currents
Maule, Radek ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
This work describes the methodology of measuring ultra low currents of the order of 10-8-10-14 [A] and the errors that arise during the measurement. This work is focused on electrical conductivity of insulation materials and interfaces electrode - dielectric during charging and discharging of the sample which is located in the ideal workplace.
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Air ionts measurement
Lazorka, Martin ; Buřival, Zdeněk (referee) ; Špinka, Jiří (advisor)
The work is focused on the composition of the atmosphere, the processes that take place in it, especially on the formation of atmospheric ions and the energy that must be supplied to ionize the gas. The work examines the influence of aerosol particles on the concentration of ions and also how air ions influence the human health. Last but not least, there is mentioned a comparison of the possibilities of artificial air ionization for interiors.
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Computer Simulation of Quadrupole Mass Filter
Kandra, Mário ; Kolářová, Jana (referee) ; Hejč, Jakub (advisor)
At our thesis, we deal with problematics of mass spectrometry. First, we are trying to explain basic physical principles, which are used by quadrupole filter or are appearing in concomitant phenomenons. In following section we will describe theoretical nature of quadrupole mass filter, stabilization and optimalization of device. Main focus of this thesis is dedicated to simulation of quadrupole mass filter and influence of parameters on trajectory of ion movement.
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Design of a new ion counter for the nature environment
Roubal, Šimon ; Szabó, Zoltán (referee) ; Roubal, Zdeněk (advisor)
Subject of this bachelors thesis is an realization of new control board for iontmeter that is developed at UTEE. Iontmeter must be capable of fully autonomous measure in outside contitions. That means it has to be able to run on batery for a long time and has to be to resist outside weather conditions. Measured data will be saved on an SD card and also sent using GSM network to the IoT server.
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Preparation of sample cross-sections and analysis by SIMS
Karlovský, Juraj ; Pechal, Radim (referee) ; Bábor, Petr (advisor)
This thesis studies possible methods of semiconductor sample measurement by SIMS, with emphasis on testing different measurement parameters and sample preparation. Part of this master thesis deals with the design of a modified sample holder compatible with the used ToF-SIMS$^{5}$ instrument, IONTOF company, which is capable of tilting the sample by defined angle. This holder enables sample preparation in the main chamber of the instrument without the need of transferring the sample between instruments, which limits the probability of sample contamination. This sample holder was tested by ion machining of TIGBT sample edge and by imaging of a crater edge, created in previous measurement. Edge termination structures prepared by different techniques were measured on the TIGBT samples. Further measurements with the goal of optimizing the depth resolution for thin layers were done on Molybdenum-Silicon-multilayer X-Ray Mirror. Part of the measurements was focused on comparing depth profiles measured at low temperatures. For these measurements the samples with Indium multilayers in GaN substrate were used.
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