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Development of the Atom and Ion Beam Sources
Tihlařík, Jan ; Voborný, Stanislav (referee) ; Mach, Jindřich (advisor)
This text is oriented for problems of creating ion beams. Thesis also describe the impact of ion optics to ion beam profile and preparing GaN layers. Also ion-atom source optimization and analysis of beam properties are there described. Also it was made deposition of GaN ultrathin layers on Si(111)dH at room temperature for different settings of atom-ion source electric electrodes.
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Optimization of devices for deposition GaN nanostructures
Šimek, Daniel ; Voborný, Stanislav (referee) ; Mach, Jindřich (advisor)
This bachelor thesis deals with the automation of sources for the deposition of GaN nanocrystals used at the Institute of Physical Engineering. For the purpose of the thesis, the mechanism of automatic control of the gallium effusion cell shutter was designed and constructed and the control electronics containing components enabling automatic switching of the ion atomic source of nitrogen ions. In addition, samples of GaN nanocrystals on four different substrates that were studied for cold electron emission were prepared by the method of ion beam assisted molecular beam epitaxy IBA-MBE. The results of the measurement are discussed in the conclusion.
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Assemblage and testing of the device for water ozonizing and its application for silicon wafer cleaning
Ředina, Dalibor ; Mikulík, Petr (referee) ; Voborný, Stanislav (advisor)
Deionised-ozonated water, so-called DIO3 appears to be an ideal alternative for usage in semiconductor industry. The utilisation of DIO3 for removal of photoresist from silicon wafers is faster, cheaper, and more environmental-friendly compared to classical technology based on mixture of sulphuric acid with hydrogen peroxide, so-called SPM. The diploma thesis deals firstly with research into ozone and ozonated water and their possible applications. Next sections describe two prototypes of generators for DIO3, that were assembled in CSVG a.s. Testing of parameters for generators on dissolved-ozone concentration is also a part of this thesis. Moreover, thesis involves tests, that were carrier out in ON Semiconductor in Rožnov pod Radhoštěm. These tests compare efficiency of cleaning by classical technology based on SPM and DIO3 approach.
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Preparation of GeSn nanostructures
Jedlička, Jindřich ; Voborný, Stanislav (referee) ; Kolíbal, Miroslav (advisor)
This bachelor thesis deals with the methods of preparation of GeSn nanowires. In the theoretical part of the thesis the band structure of solid states is described and the interesting properties of GeSn material are mentioned. The growth mechanism of nanowires and methods of preparation of GeSn nanowires are introduced. In the experimental part of the thesis the effusion cell for Sn deposition was assembled and the testing and calibration were performed.
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Optimization of ion source with saddle field
Zálešák, Marek ; Voborný, Stanislav (referee) ; Mach, Jindřich (advisor)
The goal of my bachelor's thesis was to make literature search about ion source applications. The next goal was to create models of saddle field ion source and find the best settings of the ion source. At first the most necessary changes were made to make the ion source operational. Then the deflection optics was developed that cause a deviation of the beam from the geometric axis of the ion source.
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Selective gallium nitride thin-film growth on substrates covered by pyrolyzed resist mask
Novák, Tomáš ; Kostelník, Petr (referee) ; Voborný, Stanislav (advisor)
This thesis deals with deposition of GaN thin films and GaN selective growth utilizing pyrolyzed resist masks. Carbon masks were prepared on silicon substrates by electron-beam litography and resist pyrolysis. As a further step, Ga and GaN were deposited on the masked substrates by Moleculer Beam Epitaxy (MBE) method. A selective growth of Ga droplets was achieved. These results were used for preparation of GaN crystallites by pulse deposition. It is also shown that direct MBE deposition of GaN on the masked substrates leads to a selective growth of GaN thin films with GaN film growing only on the areas which are not covered by the carbon mask. The results are explained by enhanced surface diffusion of gallium atoms on the surface of the carbon mask.
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Optimization of the Colutron Ion Source
Horký, Michal ; Mach, Jindřich (referee) ; Voborný, Stanislav (advisor)
This bachelor’s thesis concerns with design and assembly of Colutron ion source which produces beam of nitrogen ions with energy from tens to thousand eV. Production of ions and the principle of Colutron ion source is described in the first part. The second part of the thesis is related to the modification and assembly of commercial Colutron ion source. Finally the parameters of the ion beam have been measured for different extraction electrodes and operating parameters in testing apparatus.
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Study of CO oxidation on platinum by Auger spectroscopy
Hrůza, Dominik ; Voborný, Stanislav (referee) ; Bábor, Petr (advisor)
In the presented bachelor thesis, I deal with the study of the oxidation of carbon monoxide on platinum using Auger spectroscopy. In the introduction, I will describe the used methods. Furthermore, I theoretically describe the investigated reaction and indicate the measurements for a better understanding of the reaction. Then I will establish an experimental part, where I deal with the growth of graphene structures. This will be followed up by performing in-situ observations of the reaction with and without the presence of graphene. These measurements I compare and then analyse the surface composition during the reaction. Finally, I will create a methodology that can distinguish the individual molecules on the surface of the catalyst.
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Tomographical analysis of semiconductor devices by FIB-SIMS
Mičulka, Martin ; Voborný, Stanislav (referee) ; Bábor, Petr (advisor)
This thesis deals with a tomographic analysis of the structure of through-silicon via utilizing TOF-SIMS; a method used in electrotechnical industry. A focused ion beam isused to create a cross section of a semiconductor to reveal its inner structure. Afterwards a newly created surface is analysed by TOF-SIMS to determine its chemical composition. A series of 2D images is created which are used for tomographic reconstruction of the through-silicon via. Moreover, the thesis deals with an optimization of FIB-SIMS method by employing oxygen ion beam for improvement of ionized sputter yield and for artifacts reduction. A measurement of instability of bismuth ion beam is demonstrated as well.
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