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Advanced techniques of micromachining
Šalomoun, Vojtěch ; Prášek, Jan (referee) ; Pekárek, Jan (advisor)
Fabrication of micro-electro-mechanical systems (MEMS) requires advanced level of miniaturization, which is not achievable by technology used in microeletronics. Socalled micromachining covers many unique techniques of material processing to get microstructures with possible dimensions below 1 m. This bachelor’s thesis gives a general introduce to micromachining of MEMS. Its focus is on bulk and surface micromachining by wet and dry etching. The practical part contains design of microstructures, their manufacturing process and creation of computer models in CoventorWare suite.
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Optimization of PCB Process Developing and Etching
Nerušil, Petr ; Zatloukal, Miroslav (referee) ; Starý, Jiří (advisor)
Bachelor´s thesis deals with photoresist developing and copper etching – these ones are the key operations in the double layer PCB production realised with pattern plating subtractive technique. Test pattern and a schematic diagram of the technological process for quality control in the practical part. Main part of this thesis is focused to operations of photoresist developing and to inspection and evaluation of photoresist width changes on test pattern during developing and etching including copper etch factor.
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Low power MEMS heating membrane
Svatoš, Vojtěch ; Pekárek, Jan (referee) ; Hubálek, Jaromír (advisor)
The aim of this thesis is to create the MEMS heating membrane with low power consumption. This work includes the main of design and fabrication processes of these heating elements. It was decided that the final sample will be created as suspended membrane type of the structure. It the end of the thesis there is detailed overview of the whole fabrication processes used for fabrication of final samples and the experiment to prove the resistance due to thermal stress.
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Nanoelectrodes for biophysical measurements
Márik, Marian ; Hrdý, Radim (referee) ; Hubálek, Jaromír (advisor)
The aim of the project is formation of nanoelectrodes on the silicon wafer surface by thin-film techniques combined with lithography and nanotechniques developed in LabSensNano. Project is engaged in lithography and in preparation of silicon wafers. Furthermore is proposed a brief proposal of electrodes, proposal of realization and current state of the experiment.
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Properties of electrode materials for alcaline accumulators
Fusek, Petr ; Vrbický, Jiří (referee) ; Sedlaříková, Marie (advisor)
The Bachelor´s Thesis is aimed at the problematic of the binders, that effects the features of the positive electrode of alcalic accumulators. The additive used on nickel´s electrode was cobalt. In the practical part of this thesis there is described a process for etching the nickel electrode and the following electrodepositions applied on these electrodes. Measurements of different concentrations of nickel and cobalt were examined and analysed in the graphs which are part of this thesis. There have been made comments of these graphs and the conclusions and observations as well.
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New electrode structures for alkaline accumulators
Fusek, Petr ; Novák, Vítězslav (referee) ; Vrbický, Jiří (advisor)
Master´s thesis is focused on development of electrodes used in alcaline accumulators, by using new kinds of materials and compounds. Basic possitive eletrode was made of nickel, on this electrode were applied new layers of Ni(OH)2 by using the method called electrodeposition. For electrodeposition was used solution with Ni(NO3)2 in diverse concentrations. Later on, this material was enriched with aluminium admixtures to increase stability of alfa modification in Ni(OH)2. These concentrations were measured and analysed in diagrams. For measurement was used device Biologic. The diagrams were commented with recommendations for production use in accumulators.
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Optimizing of Polymer Surface Treatment for Microscopic Examination
Horská, Pavlína ; Poláček, Petr (referee) ; Bálková, Radka (advisor)
Supramolecular structure of eight commercial types of iPP, its blends with poly(L-lactide) (PP-PLLA) and copolymers with ethylene-propylene rubber (PP-EPR) together with four types of polyethylene (LDPE, HDPE) was uncovered and observed in this work. The spherulitic structure of iPP and PE homopolymers and PP copolymers was uncovered by etching of six different solutions of mineral acids with KMnO4 and by dissolution in four selected solvents. The latter was found to be ineffective. The structure of PP-PLLA blends was uncovered only after recrystallization (the change of structure by annealing and cooling rate). The uncovered crystalline structure was observed directly by confocal laser scanning microscope (CLSM) and SEM. Crystallinity together with a size distribution of crystallites was determined by DSC. It was proved that spherulitic supramolecular structure was easy to uncover by chemical etching only for molded samples and for fracture surfaces of injected samples. The efficiency of etchants varied but, generally, the samples with high degree of crystallinity were etched earlier. The etchants containing nitric acid and high content of sulphuric acid uncovered fine details of shperulites with respect to mixtures containing orthophosporic acid. It was also observed that not only the etchant (especially with nitric acid) itself but also its vapors were effective. The structure was revealed later but the appearance was plastic (3D) and the structure was very fine. The supramolecular structure of PP-PLLA blends differed with amount of each component. The ethylene-rubber phase came forth with increasing time of etching while PP spherulites disappeared in PP-EPR samples. CLSM was shown to be very good tool for observing supramolecular structure of studied samples with respect to SEM, which was proved to be entirely unsuitable for polyolefines. DSC is recommended to be performe before uncovering supramolecular structure for basic information about proportion of amorphous/crystalline phase and size of crystallites.
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Fabrication of micro- and nanostructures by different etching methods
Těšík, Jan ; Urbánek, Michal (referee) ; Šamořil, Tomáš (advisor)
The selective etching is currently very widely used method for the preparation of micro- and nanostructures. This thesis deals with the principles of the etching methods, their applications and also the possibilities of dry and wet etching at the Institute of Physical Engineering. The experimental part is devoted to the preparation of the etching masks to ensure etching selectivity and to the preparation of pre-defined micro- and nanostructures. Important parameters were determined from the results, e.g. Si etch rate, selectivity of the masks etc. Further, the suitability of the used methods and etching masks were compared.
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Chemical Machining Technology
Macháček, David ; Kolář, Ladislav (referee) ; Osička, Karel (advisor)
This bachelor thesis describes the most used methods of chemical machining in the industry. There are discussed the basic principles of particular methods, their advantages and disadvantages, as well as their best use in terms of economics. The properties of used chemicals and basic safety in working with them are also mentioned.
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