In this work, we have utilized an ion beam process known as gettering to migrate implanted Ni ions much deeper into the bulk substrate than their initial projected end of the range. The projected mean depth is known as Rp. The gettering effect is the most crucial part of the fabrication and we have found that for an H fluence of 3x 1016 cm-2 there is a threshold fluence of approximately 7.5 x 1015 cm-2 that cannot be surpassed if the gettering process is to be completed along with the substrate recovered to the high crystalline quality. This hard threshold is due to the gettering process relaxation induced mechanism that is responsible for migrating the Ni to the Rp/2 location while the H is vacating during the thermal annealing process. If the total number of vacancies produced by the H dissociation is not substantially larger than the total number of implanted Ni atoms the Ni will migrate to the Rp location of the Ni implantation at the amorphous and crystalline interface and toward the surface. When the gettering condition is not met the resulting magnetic responses vary from an exceptionally weak ferromagnetic response to not exhibiting a magnetic response. Additionally, conducting the ion implantation at an elevated substrate temperature does not increase the threshold Ni fluence above our established limit. During the elevated substrate temperature implantation, the hydrogen ions diffuse out to the surface resulting in less migration of the Ni to the initial Rp location within the Ni implantation region. The elevated temperature implantation condition appears to not create a sharp amorphous crystalline interface at the end of the range for the Ni implantation.

Diante da crescente necessidade de materiais com melhores propriedades para aplicações nos diversos campos da ciência e da tecnologia, a irradiação com feixes iônicos mostra-se como uma importante ferramenta de modicação de materiais. A irradiação de polímeros, em especial, fornece sempre novas perspectivas de aplicabilidade para esses materiais. Diante disso, o presente trabalho tem como objetivo estudar quais são e como ocorrem os processos de modicação de polímeros irradiados com feixes de íons de alta energia. Para essa investigação, amostras de politetrauoroetileno (PTFE) e poli éter éter cetona (PEEK) foram irradiadas no acelerador Unilac do GSI Helmholtzzentrum für Schwerionenforschung GmbH, em Darmstadt, Alemanha, com feixes de íons C, Xe, Au e U, de energia entre 3,6 e 11,4 MeV/u. As amostras foram submetidas à irradiação sob temperatura ambiente e temperatura criogênica (20-40 K). A análise das amostras irradiadas foi realizada através das seguintes técnicas: análise de gases residuais (RGA), espectroscopia de absorção UV-Vis, espectroscopia de absorção no infravermelho com transformada de fourier (FTIR) e difração de raios X (XRD). Observou-se que durante a irradiação do PTFE, os principais processos de modicação são as quebras moleculares e a formação do radical CF3 como grupo terminal e lateral. Além desses, também ocorrem processos de entrelaçamento e formação de estruturas insaturadas, com ligações duplas internas e terminais. Os principais fragmentos voláteis são o CF e o CF3. Durante a irradiação do PEEK observou-se liberação de gás hidrogênio em grande quantidade, como consequência da quebra dos anéis aromáticos do polímero. Algumas reações de recombinação deram origem a formação dos grupos alcino, éster, uorenona e álcool. Além disso o processo de carbonização da amostra foi responsável pelo aumento da condutividade do material. Durante a irradiação sob temperatura criogênica, alguns processos de recombinação nos materiais foram dicultados e grande parte dos elementos voláteis gerados permaneceu congelada no interior do polímero, sendo liberada durante posterior aquecimento até temperatura ambiente. Alguns modelos propostos para explicar efeitos de degradação térmica ou após irradiação com feixe de elétrons foram estendidos com sucesso aos resultados da irradiação com íons pesados e de alta energia. / Nowadays the demand for materials with improved properties for application in different elds of science and technology is constant. Ion beam irradiation is a usual and important tool of modication of materials and polymer irradiation, in particular, has given new perspectives of use for these modied materials. Hence, the aim of this work is the identication of the processes of modication of polymers irradiated with high energy ion beams and how they occur. In this investigation, samples of polytetrauorethylene (PTFE) and poly-ether etherketone (PEEK) were irradiated at the Unilac accelerator at GSI Helmholtzzentrum for Schwerionenforschung GmbH, at Darmstadt, Germany, with C, Xe, Au and U beams with energy between 3.6 and 11.4 MeV/u. The samples were irradiated at room and cryogenic (20-40 K) temperature. The sample analyses were performed through: Residual Gas Analysis (RGA), UV-Vis Absorption Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and X Ray Diraction (XRD). Under irradiation, the main processes of modication of PTFE were the chain scissioning and the formation of CF3 terminal and side group. Besides that, cross-linking and new unsaturated structures were also observed, evidenced by the formation of terminal and internal double bonds. CF3 and CF were the main degassed fragments that were observed. During irradiation of PEEK, a great amount of hydrogen gas was liberated as a consequence of the scission in the aromatics rings. Some rearrangement reactions occurred and gave rise to formation of the following groups: alkyne, esther, uorenon and alcohol. Moreover, the process of carbonization in the sample caused an increase in the polymer conductivity. When irradiated under cryo-temperature some recombination processes became more dicult and most of the volatile fragments remained frozen in the polymers. Some degradation models proposed to explain damage effects after thermal and electron beam exposure were sucessfully extended to the obtained results in the case of irradiation with swift heavy ions.

Diante da crescente necessidade de materiais com melhores propriedades para aplicações nos diversos campos da ciência e da tecnologia, a irradiação com feixes iônicos mostra-se como uma importante ferramenta de modicação de materiais. A irradiação de polímeros, em especial, fornece sempre novas perspectivas de aplicabilidade para esses materiais. Diante disso, o presente trabalho tem como objetivo estudar quais são e como ocorrem os processos de modicação de polímeros irradiados com feixes de íons de alta energia. Para essa investigação, amostras de politetrauoroetileno (PTFE) e poli éter éter cetona (PEEK) foram irradiadas no acelerador Unilac do GSI Helmholtzzentrum für Schwerionenforschung GmbH, em Darmstadt, Alemanha, com feixes de íons C, Xe, Au e U, de energia entre 3,6 e 11,4 MeV/u. As amostras foram submetidas à irradiação sob temperatura ambiente e temperatura criogênica (20-40 K). A análise das amostras irradiadas foi realizada através das seguintes técnicas: análise de gases residuais (RGA), espectroscopia de absorção UV-Vis, espectroscopia de absorção no infravermelho com transformada de fourier (FTIR) e difração de raios X (XRD). Observou-se que durante a irradiação do PTFE, os principais processos de modicação são as quebras moleculares e a formação do radical CF3 como grupo terminal e lateral. Além desses, também ocorrem processos de entrelaçamento e formação de estruturas insaturadas, com ligações duplas internas e terminais. Os principais fragmentos voláteis são o CF e o CF3. Durante a irradiação do PEEK observou-se liberação de gás hidrogênio em grande quantidade, como consequência da quebra dos anéis aromáticos do polímero. Algumas reações de recombinação deram origem a formação dos grupos alcino, éster, uorenona e álcool. Além disso o processo de carbonização da amostra foi responsável pelo aumento da condutividade do material. Durante a irradiação sob temperatura criogênica, alguns processos de recombinação nos materiais foram dicultados e grande parte dos elementos voláteis gerados permaneceu congelada no interior do polímero, sendo liberada durante posterior aquecimento até temperatura ambiente. Alguns modelos propostos para explicar efeitos de degradação térmica ou após irradiação com feixe de elétrons foram estendidos com sucesso aos resultados da irradiação com íons pesados e de alta energia. / Nowadays the demand for materials with improved properties for application in different elds of science and technology is constant. Ion beam irradiation is a usual and important tool of modication of materials and polymer irradiation, in particular, has given new perspectives of use for these modied materials. Hence, the aim of this work is the identication of the processes of modication of polymers irradiated with high energy ion beams and how they occur. In this investigation, samples of polytetrauorethylene (PTFE) and poly-ether etherketone (PEEK) were irradiated at the Unilac accelerator at GSI Helmholtzzentrum for Schwerionenforschung GmbH, at Darmstadt, Germany, with C, Xe, Au and U beams with energy between 3.6 and 11.4 MeV/u. The samples were irradiated at room and cryogenic (20-40 K) temperature. The sample analyses were performed through: Residual Gas Analysis (RGA), UV-Vis Absorption Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and X Ray Diraction (XRD). Under irradiation, the main processes of modication of PTFE were the chain scissioning and the formation of CF3 terminal and side group. Besides that, cross-linking and new unsaturated structures were also observed, evidenced by the formation of terminal and internal double bonds. CF3 and CF were the main degassed fragments that were observed. During irradiation of PEEK, a great amount of hydrogen gas was liberated as a consequence of the scission in the aromatics rings. Some rearrangement reactions occurred and gave rise to formation of the following groups: alkyne, esther, uorenon and alcohol. Moreover, the process of carbonization in the sample caused an increase in the polymer conductivity. When irradiated under cryo-temperature some recombination processes became more dicult and most of the volatile fragments remained frozen in the polymers. Some degradation models proposed to explain damage effects after thermal and electron beam exposure were sucessfully extended to the obtained results in the case of irradiation with swift heavy ions.

This thesis reports the effects of ultrashort laser pulse irradiation of various materials. The morphology after irradiation was examined using several microscopy techniques. Emphasis was placed on the identification of crystallographic changes and the analysis of laser-induced periodic surface structures. Grooves were machined in silicon by translating the target under the focused laser beam. The resulting depths were measured as a function of pulse energy, translation speed, and number of consecutive passes, for 800 and 400nm wavelength irradiation. The wall morphology and a corrugation along the bottom of the grooves were characterized. Various polarization configurations relative to the translation direction were compared. Such characterizations are relevant for the practical application of femtosecond laser micromachining. Silicon and gallium phosphide exhibited periodic structures after irradiation using photon energies less than the bandgap energy, with periods as small as ~20% of the irradiation wavelength. The significantly sub-wavelength periodic structures had a shallow profile on silicon, appearing as fine lines or grids of protrusions and depressions. On gallium phosphide, the surface evolved into planar-like structures with a large aspect ratio, possessing crystalline centers coated with amorphous material. These investigations, along with additional experiments, would help identify the precise physical origins of the short-period structures. On silicon and germanium, the target crystal orientation was shown to affect the formation of certain morphological features. For multiple-pulse irradiation, the (100) and (111) surface orientations exhibited significantly different tendencies for large conical structure formation. A thin layer of defected material coated the conical structures, with some defects present within the periodic structures. The different crystalline orientations did not affect periodic structuring. Cross-sectional transmission electron microscopy of silicon after irradiation by single pulses revealed amorphous material and dislocations in the bulk for sufficiently high pulse fluences. On a sample consisting of a metal layer on thermally-grown oxide on silicon, a range of pulse fluences was found which removed the metal layer without observed thinning of the oxide layer. Within this fluence range, above a particular fluence substantial defects were formed in the underlying silicon. Although ultrashort pulse irradiation of materials is frequently considered to be 'damage-free', attention should be paid to sub-surface modifications not evident from surface imaging. For the drilling of holes in copper foils, the pulse duration did not strongly affect the final morphology for durations under several picoseconds. A photodiode below the foil during drilling recorded transmitted light, indicating the number of pulses required for penetration under a variety of conditions, and characterizing hole evolution during drilling. Periodic surface structuring on the walls of holes depended on the irradiation atmosphere, pulse duration, and laser polarization. These measurements provide insight into the physical processes of material modification, and for the selection of irradiation parameters in practical applications. / Thesis / Doctor of Philosophy (PhD)

The diploma thesis is focused on the verification of the parameters of thin lightweight mineral plasters with modified composition. As alternative raw materials are used expanded perlite Vapex, calcined diatomite Celite and powder waste glass of fluorescent lamps. In the theoretical part is summarized knowledge from completed studies dealing with the issue of compensation porous filler component. In the experimental part is tested consistency of fresh mixture, physical-mechanical, sorption and thermal insulating characteristics. It is compared the appearance of the surface and summarized the results of measuring.