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Advanced techniques of micro- and nanosystems fabrication for sensors
Márik, Marian ; Pekárek, Jan (referee) ; Hubálek, Jaromír (advisor)
The use of micro- and nanotechnologies is necessary in the development of advanced sensor systems. In this thesis few selected technologies were studied and tested on fabrication of creating two different systems for bioelectrical and electrochemical applications. For biolelectrical applications a chip with a pair of gold nanoelectrodes was designed and implemented. For electrochemical analysis a novel two electrode system was designed and realized, which should contribute by greater sensitivity and accuracy in amperometric detection compared with three-electrode systems in voltammetric analysis. The fabricated systems were tested and the results were discussed.
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Testing of the new UHV scanning electron microscope and design of its effusion cel
Šárközi, Rudolf ; Mach, Jindřich (referee) ; Bábor, Petr (advisor)
This work focus on the development and the design of the effusion cell that is able to deposit different materials in downward orientation. The Cell itself should be placed into the ultra-vacuum microscope (UHV-SEM) developed in TESCAN company in the collaboration with Institute of Physical Engineering. Theoretical part is devoted to the description of the electron microscope and its, in the future installed, parts, which will be used for the preparation and the analysis of the nanostructures. In this work, the first measurements with the electron microscope are presented, and the influence of mechanical vibrations to image quality is discussed.
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Interaction of a SNOM tip with electromagnetic near-field produced by interference of surface plasmon polaritons
Jakub, Zdeněk ; Břínek, Lukáš (referee) ; Dvořák, Petr (advisor)
The aim of this bachelor’s thesis is fabrication of probes for scanning near-field optical microscope (SNOM) and testing of their functionality by measuring interference patterns of surface plasmon polaritons (SPP). The theoretical part deals with the basic properties of SPP’s and methods of their excitation and detection. In the experimental part, methods of sharp tip fabrication by chemical etching, thin film deposition by ion beam sputtering (IBS) or by ion beam assisted deposition (IBAD) and aperture opening by focused ion beam (FIB) are explained and demonstrated. Finally, interference patterns of SPP’s are measured with fabricated probes and the results are compared with the results obtained with commercially available probes.
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Determination of mechanical properties from microcompression test
Truhlář, Michal ; Kruml, Tomáš ; Kuběna, Ivo ; Petráčková, Klára ; Náhlík, Luboš
This paper describes a microcompression test of Al - 1.5 wt. % Cu thin film deposited on Si substrate. Microcompression combines the sample preparation with the use of ion focused beam (FIB) with a compression test carried out using nanoindenter. Cylindrical specimens (pillars) were prepared using FIB. The diameter of pillars was about 1.3 μm and their height was about 2 μm (equal to the film thickness). Stress-strain curves of the thin film were obtained. The results depend on crystallographic orientation of pillar. The paper is focused to an attempt to determine as precisely as possible Young modulus of the film using experimental data and finite element modelling.
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Estimation of mechanical properties of thin Al surface layer
Petráčková, Klára ; Kuběna, Ivo ; Truhlář, Michal ; Náhlík, Luboš ; Kruml, Tomáš
The paper describes a new method for testing of thin layers, so-called microcompression test. As an example determination of Al thin film properties deposited on Si substrate is introduced in the paper. Microcompression combines the sample preparation with the use of focused ion beam (FIB) with a compression test carried out using nanoindenter. Cylindrical specimens (pillars) were prepared in Al film using FIB. The typical diameter of pillars was about 1.3 μm and their height was about 2 μm. The results depend on crystallographic orientation of pillar. Stress-strain curves of the thin film were obtained. Experimentally measured data on pillars needs correction to obtain undistorted material properties of Al thin film. A necessary correction using finite element modeling is suggested in the paper. The paper contributes to a better characterization of very thin surface layers and determination of their mechanical properties.
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Mechanical properties of Al thin films measured by microcompression
Kuběna, Ivo ; Kruml, Tomáš
Two modern experimental techniques, the focused ion beam milling and the nanoindentation, were applied in order to measure exactly plastic properties of a Al-1.5%Cu thin film prepared by the physical vapour deposition, used for electrical connection of integrated circuits. By focused ion beam milling, cylindrical specimens were prepared. The height of the specimens was equal to the film thickness (2 micrometers) and their diameter was about 1.3 micrometers. These specimens were subjected to the compressive loading using the nanoindenter equipped by a flat punch. It is possible to obtain stress-strain curves of the thin film rather precisely.
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Nanocompression of oriented pillars from Al thin film
Kuběna, Ivo ; Kruml, Tomáš
In this paper, a new method of measurement of mechanical properties of thin films is presented. This method combines specimen preparation by focused ion beam (FIB) and compression test using nanoindentation device. Compression specimens were prepared from thin film, Al-1.5%Cu, which is commonly used in integrated circuit. Cylindrical specimens were prepared by FIB milling. The height of specimens (pillars) was about 2 mircrometers (equal to the film thickness) and their diameter was about 1.3 micrometers. The pillars are single crystalline, therefore the results depend on crystallographic orientation of pillar, which was specified by EBSD (electron backscatter diffraction). Stress-strain curves of the thin film were obtained in two representations.
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Determination of mechanical properties of thin films by nanocompresion
Kuběna, Ivo ; Hutař, Pavel ; Náhlík, Luboš ; Kruml, Tomáš
Measurements of mechanical properties of objects with micrometric (or even smaller) dimensions is still not a common task. In this paper, the possibility of evaluation basic mechanical properties of a thin film by nanocompression is demonstrated. Cylindrical specimens with the axis normal to the film plane, attached by the bottom to the substrate, are prepared by the focused ion beam technique. Such pillars are deformed by a nanoindenter outfitted by a flat diamond punch. An equivalent of compression curve is obtained. It is possible to measure directly parameters as the yield stress, stress at a chosen strain level or work hardening rate. Finite elements modelling is necessary for the Young modulus evaluation. It is shown that the Young modulus can be evaluated quite precisely, even if the geometry of the pillar is not perfect.
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Optimization of preparation of microcompresion specimens from thin films films using focused ion beam
Kuběna, Ivo ; Kruml, Tomáš
In this paper new method of mechanical properties measurement of thin films is presented. This method combines preparation of specimen using focused ion beam and compressive test by nanoindenter. This paper is focused on description of the preparation microcompressive specimens. The thin film Al – 1.5 wt. % Cu was studied. The cylindrical pillars had diameter about 1.3 micrometers and their height was determined by thickness of layer (2 micrometers). The optimized reproducible process of the preparation of the microcompressive specimens was found. This process is optimized from geometry and preparation time point of view. Successfully executed compressive tests confirmed suitability specimens for microcompressive test
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