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Self-sensing SPM probes for measuring electrical properties of materials
Očkovič, Adam ; Vařeka, Karel (referee) ; Pavera, Michal (advisor)
The bachelor's thesis is focused on the modification of probes with an integrated sensor usable for measuring conductivity characteristics of surfaces in atomic force microscopy. The first part presents the theory concerning atomic force microscopy, conductivity measurement and deposition using an ion beam. Furthermore, the method of production and limitation of the use of electrically conductive probes with optically read deflection is described. The practical part presents the main problems of probes with integrated sensors in conductivity measurements. Furthermore, the modification of the probes themselves, the measurements made with these probes and suggestions for improving the properties of the probes are described.
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Scanning probe microscopy scanner with high resonant frequency
Krupa, Matyáš ; Dostál, Zbyněk (referee) ; Pavera, Michal (advisor)
The thesis deals with the design of the scanning probe microscopy scanner with a higher resonant frequency. The first part of the thesis is focused on theory as the principle of atomic force microscopy, function of the scanner and its properties. The second part describes the gradual development of a new microscope. The mechanical simulations used to determine the properties of scanners are introduced first. Furthermore, the thesis deals with the design for the x, y axis and then also for the z axis. In conclusion, the final design of a three-axis scanner with a higher resonant frequency is presented.
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Advanced SPM techniques for measuring electrical properties of materials
Kramář, Jan ; Konečný, Martin (referee) ; Pavera, Michal (advisor)
This bachelor thesis is concerned about development of local electric properties characterization technique of sample in contact mode of Atomic Force Microscopy. The research part describes the most expanded techniques of characterization of local electric properties using Scanning Probe Microscopy. For realization was chosen Scanning Spreading Resistance Microscopy. Important part of this technique is current amplifier. For that reason, operational amplifiers, circuits with them and implementation of new amplifier on microscop are described. Last chapter is dedicated to description of samples, which were used to test functionality of the amplifier and technique.
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Correlated probe and electron microscopy for the study of modern magnetic nanomaterials
Novotný, Ondřej ; Flajšman, Lukáš (referee) ; Pavera, Michal (advisor)
High pressure on the development of new magnetic materials and their miniaturization also emphasizes the development of new analytical techniques. This diploma thesis deals with the development and demonstration of correlated magnetic force and electron microscopy, which is a promising tool for the characterization of magnetic nanomaterials. The first part of this thesis describes the fundamental physics of micromagnetism with a focus on cylindrical nanofibers. The following pages describe optic, probe, electron, and synchrotron methods for mapping the magnetic properties of materials. The next part describes magnetic domain wall motion in cylindrical nanowires performed as a part of a more extensive material study. The last part of the thesis describes the development of correlated magnetic force and electron microscopy on LiteScope device. A production of magnetic probes was designed and successfully tested. Probes were fabricated by focused electron beam-induced deposition from the Co2(CO)8 precursor. Further, the developed correlated microscopy is demonstrated on a multilayer PtCo sample, magnetic cylindrical nanofibers, NiFe vortex structures, and FeRh metamagnetic nano-islands.
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Use of a special optical fiber in an electron microscope chamber
Černek, Ondrej ; Konečný, Martin (referee) ; Pavera, Michal (advisor)
This bachelor thesis is concerned about the modification of vacuum chamber of the Scanning Electron Microscope VEGA developed by TESCAN Brno s.r.o. in order to implementation of Scanning Probe Microscope. Moreover, it is dedicated to development of apparatus for using hollow optical fiber allowing the guidance of light and various gases on the sample surface placed in the vacuum of electron microscope. By using the hollow optical fiber as a probe of Scanning Probe Microscope, it is possible to work with a tip with specific properties. A brief introduction to Scanning Electron Microscopy and Atomic Force Microscopy is presented in the theoretical part. Furthermore, there is a technique of using optical fibers in Scanning Near-field Optical Microscopy described. Also a problem of vacuum systems, gas flow through the pipe and technique of Gas Injection System is introduced. In the construction part, there are initiated steps in the development of the vacuum chamber and the apparatus allowing the guidance of hollow optical fiber into the chamber of microscope. The experimental part presents the result of measurements obtained by probe of Scanning Probe Microscope with modified optical fiber and gas transmissivity of hollow optical fiber.
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Mechanical excitation of self sensing SPM probes
Novotný, Ondřej ; Piastek, Jakub (referee) ; Pavera, Michal (advisor)
This bachelor thesis deals with the development of the SPM microscope probe holder which is designed for mechanical excitation of the probes. The first part of the thesis focuses on the description of physical theory, such as the principle of atomic force microscopy, the function of piezoceramics and the description of used quartz tunning fork based probes. The second part describes the gradual development and design of the new probe holder. Testing of the designed probe holder and comparison of mechanical and electric excitation is depicted at the end of this work. The designed probe holder was manufactured, the assembly procedure was described, and the drawings of the individual parts were created.
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Development of probes for combined magnetic force microscopy and electron microscopy
Láznička, Tomáš ; Švarc, Vojtěch (referee) ; Pavera, Michal (advisor)
This thesis deals with the production of magnetic probes for Magnetic Force Microscopy. For production, it was necessary to construct a device that can be used to make magnetic probes from commercial AFM probes. The requirements for the holder for deposition are specified, mechanical designs of six proposals which have been improved are discussed and further is described a production of magnetic probes. In a special chapter are shown deposited material on probe tips surface and results of testing magnetic probes.
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Local electrical conductivity measurements in AFM tapping mode
Dao, Radek ; Konečný, Martin (referee) ; Pavera, Michal (advisor)
This bachelor thesis is concerned about the development of a probe for local electrical conductivity measurements in tapping mode Atomic Force Microscopy. The teoretical part gives a short overview of Scanning Probe Microscopy techniques, with the focus being on Conductivity Atomic Force Microscopy. Furthermore, the measuring regime in which the probe operates is described here, as well as the basic component of the probe, the quartz tuning fork. The experimental part follows the iterative development process, and contains a chapter dedicated to making of very sharp tips. The final chapters describe the preparation of test samples, which were used to prove the functionality of the probe and the measurement of local electrical conductivity itself.
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Low temperature scanning tunneling microscopy
Sojka, Antonín ; Havlíček,, Marek (referee) ; Pavera, Michal (advisor)
The diploma thesis is divided into two main parts. The first part describes the production of chrome and cobalt tips for SP-STM with subsequent testing of chrome tips on the Fe-Ir system (111). Furthermore, the first results from the growth studies of niobium on iridium(111) are presented. In the second part is described in detail the experimental LT-STM microscope of the Faculty of Physical Engineering. The chapter deals with the development of the microscope and its testing on a HOPG sample under atmospheric and vacuum conditions. The chapter describes the biggest problems which were solved when the microscope was puting into operation state. The second part also introduces the design of a new vacuum transport system, which consists of a tip and sample transport pallet. At the end of the second part is described the testing of cooling systems for LT-STM and the design of their modifications.
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Preparation and testing of SNOM probes
Bobek, Juraj ; Pavera, Michal (referee) ; Spousta, Jiří (advisor)
The area of research that deals with surface modification and preparation of nanostructures is still very unexplored. And only a little contribution to this field is discussed in this bachelor thesis. Its goal is to manufacture and to test a probe made off hollow optical fibre that is used in Scanning Probe Microscopy. Optical fibre parameters in combination with proper and unique techniques allow the breakthrough off very interesting applications. It's worth mentioning the gas injection in the proximity of the surface of a sample (GIS) and thus its modification by use of electrons (FEBID), ions (FIBID) or laser beams.
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