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1	Studium tenkých vrstev molekulárních nanomagnetů připravených metodou Langmuira-Blodgettové a návrh úpravy Langmuirovy vaničky / Study of thin films of molecular nano-magnets prepared by Langmuir-Blodgett technique and drafting of an adapted Langmuir trough Vaverka, Jan January 2017 (has links) This diploma thesis focuses on studies of deposition of molecular nanomagnets doubledecker dysporsium phtalocyanine via Langmuir-Blodgett method. The thesis describes the influence of deposition parameters on structure of deposited molecular layer of doubledecker dysporsium phtalocyanine. The prepared molecular layers are analysed by X-ray reflectivity and Atomic force microscopy. Moreover, the proposal of structural changes of KSV Minimicro instrument, used for Langmuir Blodgett deposition, is described. The intended result is Langmuir trough of bigger dimensions than the recent one, which would enable to distribute molecular layers numbering about magnitude of hundreds.
2	DEVELOPING AN APPROACH TO IMPROVE BETA-PHASE PROPERTIES IN FERROELECTRIC PVDF-HFP THIN FILMS Ashley S Dale (8771429) 02 May 2020 (has links) Improved fabrication of poly(vinylindenefluoride)-hexafluoropropylene (PVDF-HFP) thin films is of particular interest due to the high electric coercivity found in the beta-phase structure of the thin film. We show that it is possible to obtain high-quality, beta-phase dominant PVDF-HFP thin films using a direct approach to Langmuir-Blodgett deposition without the use of annealing or additives. To improve sample quality, an automated Langmuir-Blodgett thin film deposition system was developed; a custom dipping trough was fabricated, a sample dipping mechanism was designed and constructed, and the system was automated using custom LabVIEW software. Samples were fabricated in the form of ferroelectric capacitors on substrates of glass and silicon, and implement a unique step design with a bottom electrode of copper with an aluminum wetting layer and a top electrode of gold with an aluminum wetting layer. Samples were then characterized using a custom ferroelectric measurement program implemented in LabVIEW with a Keithley picoammeter/voltage supply to confirm electric coercivity properties. Further characterization using scanning electron microscopy and atomic force microscopy confirmed the improvement in thin film fabrication over previous methods. Condensed Matter Physics beta phase polyvinylidene fluoride hexafluoropropylene Langmuir Blodgett Langmuir Blodgett method Thin Film Formation Thin Film Ferroelectric Thin Film Characterization Polymer Physics Condensed Matter Hysteresis LabVIEW program Arduino Arduino Uno microcontroller PVDF PVDF-HFP Ferroelectric Capacitor Ferroelectric Capacitors magnetron sputtering Coercivity scanning electron microscopy Atomic Force Microscopy
3	Developing an approach to improve beta-phase properties in ferroelectric pvd-hfp thin films Dale, Ashley S. 05 1900 (has links) Indiana University-Purdue University Indianapolis (IUPUI) / Improved fabrication of poly(vinylindenefluoride)-hexafluoropropylene (PVDF-HFP) thin films is of particular interest due to the high electric coercivity found in the beta-phase structure of the thin film. We show that it is possible to obtain high-quality, beta-phase dominant PVDF-HFP thin films using a direct approach to Langmuir-Blodgett deposition without the use of annealing or additives. To improve sample quality, an automated Langmuir-Blodgett thin film deposition system was developed; a custom dipping trough was fabricated, a sample dipping mechanism was designed and constructed, and the system was automated using custom LabVIEW software. Samples were fabricated in the form of ferroelectric capacitors on substrates of glass and silicon, and implement a unique step design with a bottom electrode of copper with an aluminum wetting layer and a top electrode of gold with an aluminum wetting layer. Samples were then characterized using a custom ferroelectric measurement program implemented in LabVIEW with a Keithley picoammeter/voltage supply to confirm electric coercivity properties. Further characterization using scanning electron microscopy and atomic force microscopy confirmed the improvement in thin film fabrication over previous methods. beta phase Polyvinylidene Fluoride hexafluoropropylene Langmuir Blodgett Langmuir Blodgett method Thin film formation Thin dilm Ferroelectric Thin film characterization Polymer Physics Condensed matter Hysteresis LabVIEW program Arduino Arduino Uno microcontroller PVDF PVDF-HFP Ferroelectric capacitor Ferroelectric capacitors Magnetron sputtering Coercivity Scanning electron microscopy Atomic force microscopy

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