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Design of micromanipulator for scanning electron microscope
Palouda, Adam ; Dostál, Zbyněk (referee) ; Nováček, Zdeněk (advisor)
This thesis describes the process of design, manufacture and testing of a device for the detection of cathodoluminescent effect in scanning electron microscope. Firstly, it summarizes the basics of electron microscopy, specifically the design and manufacture of vacuum systems. It also deals with ways of using 3D printing in the prototyping of vacuum components. Then it describes the process of development of a device, which enables the user to measure cathodoluminescence in an electron microscope. The device consists of a feedthrough for optical fibre and a micromanipulator which allows the user to position the tip of the fibre to the sample. The signal from the fibre is processed in a photomultiplier for which a case is designed as a part of this thesis, or in a spectrophotometer. During the development process the device is being tested by performing some measurements and is adjusted to increase functionality and user comfort.
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Research of advanced microscopic and lithographic AFM techniques
Vaněk, Kamil ; Černek, Ondrej (referee) ; Nováček, Zdeněk (advisor)
This bachelor’s thesis is about testing and improving the environmental chamber for atomic force microscope NTegra Prime and implementing hollow probes FluidFM to this microscope. A functional implementation of hollow probes to NTegra Prima together with the ability to control the atmosphere allows us to carry out nanolithography experiments with this setup. At first, the development of hollow probes and the system FluidFM is mentioned together with properties and applications. In next chapter, the AFM setup and environmental chamber is introduced. Testing of the chamber is described and enhancements presented. Next, the results of measurements in vacuum are mentioned. At the end, the implementation of hollow probes together with measurements are presented. These results are compares with measurement results with normal probe.
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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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Motivation for sports and physical activities in adolescents
Nováček, Zdeněk ; Hájková, Jana (advisor) ; Hrabinec, Jiří (referee)
The theme of my labour is an adolescents' and pubescents' motivation of sport. My aims are: to check that working out of students and pupils is affected by parents, to find out the most frequent reasons why students do sport and if sport offer of school affects frequency of students' working out. Pubescence and adolescence are the period of life ,when the formation relation to sport clo ses and ends. There are no significant changes during other stages of life. r d like to find out what is the relationship of youth to sport like and what are the factors supporting a positive attitude to sport.
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Motivation for sports and physical activities in adolescents
Nováček, Zdeněk ; Hrabinec, Jiří (referee) ; Hájková, Jana (advisor)
The theme of my labour is an adolescents' and pubescents' motivation of sport. My aims are: to check that working out of students and pupils is affected by parents, to find out the most frequent reasons why students do sport and if sport offer of school affects frequency of students' working out. Pubescence and adolescence are the period of life ,when the formation relation to sport clo ses and ends. There are no significant changes during other stages of life. r d like to find out what is the relationship of youth to sport like and what are the factors supporting a positive attitude to sport.
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Selective hydrogenation of graphene prepared by chemical vapour deposition
Kovařík, Štěpán ; Nováček, Zdeněk (referee) ; Bartošík, Miroslav (advisor)
Controlled bandgap opening is one of the skills necessary for the application of graphene in electronics. The graphene hydrogenation is one of the possible ways to open the bandgap. In this work we deal with local hydrogenation of graphene prepared by chemical vapour deposition on a Si/SiO2 substrate. The hydrogenation was performed by atomic source of hydrogen and polymethyl methacrylate pattern was used for localization of hydrogenated structures on graphene. The pattern was prepared by electron beam lithography. The presence of structures formed by hydrogenated graphene was investigated by Raman spectroscopy, Kelvin probe force microscopy and PeakForce tunneling atomic force microscopy. All three methods have confirmed the local hydrogenation of graphene.
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Development of Instrumental Equipment for the Characterization of Nanostructures
Nováček, Zdeněk ; Ošťádal, Ivan (referee) ; Fejfar, Antonín (referee) ; Šikola, Tomáš (advisor)
The thesis focuses on the development of instruments used for surfaces and nanostructures characterization. Individual techniques of scanning probe microscopy provide different information of the sample surface. The resolution of scanning probe microscopy, providing 3D topography information, reaches subnanometer values or even an atomic level. Therefore, the scanning probe microscopy is one of the most employed method in the field of nanotechnology. The thesis describes the details of development of two scanning probe microscopes intended for measurement under ultra high vacuum conditions. As for the first one, many changes were proposed leading to its better variability, extended functionality and increased user comfort. The second microscope is being design with the aim of its combination with other analytic techniques, especially with scanning electron microscopy. An integral part of scanning probe microscopes is a precise positioning system for navigation of the probe to the selected site. Therefore, the thesis also deals with the development of linear piezoceramic actuators used not only in the ultra high vacuum compatible microscopes but also as a general purpose nanomanipulators.
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Reconstruction of the Antenna Near-Field
Puskely, Jan ; Mazánek, Miloš (referee) ; Schejbal, Vladimír (referee) ; Nováček, Zdeněk (advisor)
Cílem disertační práce je navrhnout efektivně pracující algoritmus, který na základě bezfázového měření v blízkém poli antény bude schopen zrekonstruovat komplexní blízké pole antény resp. vyzařovací diagram antény ve vzdáleném poli. Na základě těchto úvah byly zkoumány vlastnosti minimalizačního algoritmu. Zejména byl analyzován a vhodně zvolen minimalizační přistup, optimalizační metoda a v neposlední řadě i optimalizační funkce tzv. funkcionál. Dále pro urychlení celého minimalizačního procesu byly uvažovány prvotní odhady. A na závěr byla do minimalizačního algoritmu zahrnuta myšlenka nahrazující hledané elektrické pole několika koeficienty. Na základě předchozích analýz byla navržená bezfázová metoda pro charakterizaci vyzařovacích vlastností antén. Tato metoda kombinuje globální optimalizaci s obrazovou kompresní metodou a s lokální metodou ve spojení s konvečním amplitudovým měřením na dvou površích. V našem případě je globální optimalizace použita k nalezení globálního minima minimalizovaného funkcionálu, kompresní metoda k redukci neznámých proměnných na apertuře antény a lokální metoda zajišťuje přesnější nalezení minima. Navržená metoda je velmi robustní a mnohem rychlejší než jiné dostupné minimalizační algoritmy. Další výzkum byl zaměřen na možnosti využití měřených amplitud pouze z jednoho měřícího povrchu pro rekonstrukci vyzařovacích charakteristik antén a využití nového algoritmu pro rekonstrukci fáze na válcové geometrii.
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The Analysis of Coaxial and One-wire Non-homogeneous Structures in Time Domain
Štverka, Dalibor ; Nováček, Zdeněk (advisor)
The work considers pulse wire-guided electromagnetic (EM) waves. The main contribution of the work is the original design of the isolation bushing for maximizing of the received wave (echo) thanks to the results of the numerical simulations, the acquirement of the new acknowledges of the reflections of the guided EM wave from the various boundaries, the construction of PML layers for FDTD simulations in rotational coordinates, the advances made in temporary excitation sources for FDTD and the formulation of the program code for FDTD in rotational coordinates in Matlab environment. The rightness of the numerical simulations was verified in practical experiments. The practical exploitation of the results is supposed in instrumentation and control technology - the level measurement in reservoirs.
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Design of optoelectronic positional sensor
Straka, Radomír ; Nováček, Zdeněk (referee) ; Puskely, Jan (advisor)
The aim of this semestral work is design optoelectronic positional sensor, which can measure current position of measuring line. This position has to be measure very precisely. At first the work describes positional sensors used in automatization. Work study parameters of resistance, inductance, capacity, optoelectronic and ultrasound sensors. Subsequently work choose integrated optoelectronic sensor ADNS-5020, realize with ADNS-5020 circuit for measuring position and realize part processing transmission of signal from sensor to PC with integrated circuit FT232RL. The results of this work are design measuring and transfering circuit for optoelectronic positional sensor, measuring program which have control over designed circuit. Measuring program process measured data of voltage possibly current distribution on the line and create tables and graphs with calculation reflection coefficient and impedance from data.
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