Non-Alcoholic Fatty Liver Disease (NAFLD) is characterized by accumulation of lipids in hepatocytes, which accounts for at least 5% of the weight of this tissue. It affects patients in different age groups; these tend to present hepatic alterations characterized not only by the accumulation of fat but, in some cases, also by the presence of inflammation and fibrosis, even evolving to cirrhosis. It is considered the hepatic component of Metabolic Syndrome (MS) and this, in turn, is also an inducer of NAFLD. The present study proposes to evaluate the degree of steatosis in patients with NAFLD and their relationship with cardiovascular risk, the prevalence of OSAS and quality of life. This is a cross-sectional study, where 173 patients were interviewed at the outpatient clinic. Hepatology, which is a reference service of the State, University Hospital of the Federal University of Sergipe. Socio-demographic data and anthropometric measurements, results of biochemical laboratory tests and image of medical records were collected, and these patients were submitted to quality of life (QOL) questionnaires (WHOQOL bref), CVD risk (Framinghan score), individual risk of OSAS (Berlin scale) and bioimpedance test. We obtained as results a prevalence in the low risk population to develop CVD (58.4%), a prevalence of the sample for high risk of OSAS (64%), the QV assessment showed better results in the psychological and social relations domains . We conclude that there is an association between the degree of NAFLD and the evolution of OSA in the patients studied. There was no association with the increase in the risk of CVD, and when we assessed the association with the QOL, there was no significant difference between the total score quality of life in patients with mild steatosis for individuals who presented them in marked form. Thus, we emphasize the importance of the global evaluation of these patients, from the beginning of the detection of NAFLD. / A Doença Hepática Gordurosa Não Alcoólica (DHGNA) é caracterizada por acúmulo de lipídios em hepatócitos, que representa, ao menos, 5% do peso deste tecido. Acomete pacientes em diferentes faixas etárias; estes tendem a apresentar alterações hepáticas caracterizadas não apenas pelo acúmulo de gordura, mas, em alguns casos, também pela presença de inflamação e fibrose, inclusive evoluindo para cirrose. É considerada o componente hepático da Síndrome Metabólica (SM) e esta, por sua vez, também um indutor da DHGNA. O presente estudo propõe avaliar o grau de esteatose em pacientes com DHGNA e a relação destes com o risco cardiovascular, a prevalência de SAOS e a qualidade de vida. Trata-se de um estudo transversal, onde foram entrevistados 173 pacientes atendidos no ambulatório de Hepatologia, um serviço de referência no Estado, do Hospital Universitário da Universidade Federal de Sergipe. Foram coletados dados sociodemográficos e medidas antropométricas, resultados de exames laboratoriais bioquímicos e de imagem dos prontuários, e estes pacientes foram submetidos a questionários de qualidade de vida (QV) (WHOQOL bref), risco de doenças cardiovasculares (DCV’s) (Escore de Framinghan), a avaliação do risco individual de Síndrome da Apneia Obstrutiva do Sono (SAOS) (Escala de Berlim) e ao teste de bioimpedância. Obtivemos como resultados uma prevalência na população estudada de baixo risco para desenvolver DCV’s (58,4%), houve uma prevalência da amostra para alto risco de SAOS (64%), a avaliação da QV demonstrou melhores resultados nos domínios psicológicos e das relações sociais. Concluímos que há uma associação do grau de DHGNA com a evolução do SAOS nos pacientes estudados, não havendo a mesma associação em relação ao aumento do risco de DCV’s e quando avaliamos a associação com a QV não observou-se diferença significativa entre o escore total de qualidade de vida em pacientes com esteatose leve para os indivíduos que as apresentavam na forma acentuada. Sendo assim, enfatizamos a importância da avaliação global desses pacientes, desde o início da detecção da DHGNA. / Aracaju

Orientador: Ioshiaki Doi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-08T12:57:52Z (GMT). No. of bitstreams: 1 Pereira_MarcusAnibal_M.pdf: 4318576 bytes, checksum: 61cdc38456d21cf10bf9ccfef5d0bff4 (MD5) Previous issue date: 2005 / Resumo: Isolantes de nitreto de silício (SiNx) para aplicação na tecnologia de isolação LOCOS foram depositados por ECR-CVD a temperatura ambiente e RP/RTCVD, a baixa pressão (5mTorr), com fluxos de gás de N2 de 2.5, 5, 10 e 20sccm, com fluxos de gases de SiH4/Ar fixos de 200sccm/20sccm, e potência de microondas de 1000W em substratos de SiO2-Pad/Si e Si. As estruturas de SiNx/SiO2-Pad/Si e SiNx/Si obtidas foram utilizadas para analisar as características físicas do nitreto de silício. Análises de espectroscopia de infravermelho (FTIR) revelaram a presença de trocas de posição do pico principal das ligações Si-N, das ligações N-H e das ligações Si-N (modo de vibração stretching) nos filmes de nitreto de silício, que está relacionado aos fluxos de N2 na mistura de gases. Os índices de refração entre 1.88 e 2.48 e as espessuras entre 120nm e 139nm foram determinados através de elipsometria. Com estes valores de espessura e com os tempos de ataque em Buffer de HF, foram determinadas as taxas de deposição de 9,6 a 11,1nm/min e taxas de corrosão de 2 a 86nm/min. O processo LOCOS, com etapas seqüenciais de fotolitografia e oxidação térmica, foi executado nas estruturas de SiNx/SiO2-Pad/Si e também de SiNx/Si (sem a presença de óxido "almofada"), com a espessura de cada tipo de nitreto entre 110nm a 215nm e espessura do óxido ?almofada? de 0 a 124nm. Análises de microscópio óptico e de microscopia eletrônica de varredura (SEM) foram utilizadas respectivamente para investigar a resistência dos nitretos de silício à oxidação térmica, executada sob altas temperaturas (1000ºC) e o efeito ?bico de pássaro? formado nas estruturas LOCOS. O nitreto depositado com fluxo de N2 de 10sccm (N10) foi o que apresentou a menor invasão lateral por parte do óxido de campo dentre os nitretos estudados, tanto com quanto sem a camada de óxido de ?almofada? sob o nitreto. O efeito "bico de pássaro" formado nas estruturas LOCOS teve comprimento de avanço lateral variando de 330nm a 2160nm tomando como base a oxidação local executada em temperatura de 1000ºC durante 180 minutos / Abstract: Silicon nitride (SiNx) insulators for LOCOS applications have been deposited by RP/RTCVD and ECR-CVD at room temperature, at low pressure (5mTorr), with N2 flows of 2.5, 5, 10 and 20sccm with fixed SiH4/Ar flows of 200/20sccm with a microwave power of 1000W on SiO2-Pad/Si and Si substrates. SiNx/Si structures were obtained to analyze the physical characteristics of silicon nitride. Fourier transform infrared (FTIR) spectrometry analyses revealed the main peak position shifts of Si-N, N-H and Si-N (stretching mode) bonds for each silicon nitride films, which is related to N2 flows in gas mixture. The refractive indexes between 1.88 and 2.48 and the thickness between 120nm and 139nm were determined by ellipsometry. With these thickness values and with buffered HF etching times, it was also determined the deposition rates of 9,6 - 11,1nm/min and etch rates of 2 -86nm/min. On the SiNx(110 -215nm)/SiO2-Pad(0 - 124nm)/Si and SiNx/Si (without pad oxide) structures, the LOCOS process, with sequential photolithography and thermal wet oxidation steps, was performed. Optical and scanning electron microscopy (SEM) analysis were used to investigate the silicon nitride to thermal oxidation accomplishement at high temperature of 1000 ºC, and bird's beak in the obtained LOCOS structures. On both structures (with and without pad oxide), the smallest lateral extension of the field oxide (bird's beak) was observed for the nitride films obtained with N2 flows of 10sccm (N10). The lengths of the bird's beak, in the obtained LOCOS structure, have resulted between 330nm and 2160nm / Mestrado / Eletrônica, Microeletrônica e Optoeletrônica / Mestre em Engenharia Elétrica

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Le graphène est un matériau très intéressant grâce à ses excellentes propriétés optiques, électriques et mécaniques. Parmi les méthodes de synthèse du graphène monocouche, la croissance par le dépôt chimique en phase vapeur (CVD) sur un métal est des plus efficaces et économiques pour assurer une production industrielle. Cette méthode demande toutefois une étape de transfert du graphène à partir du substrat catalytique de la croissance (généralement du cuivre) vers le substrat désiré. Plusieurs méthodes permettent d’effectuer ce transfert et les plus répandues impliquent généralement l’usage d’un polymère, car il présente des avantages intéressants, comme la simplicité et le faible coût, mais également des désavantages liés à l’introduction de défauts ou de résidus organiques sur la surface du graphène transféré. Pour conserver la qualité et les propriétés du graphène après le processus de transfert, nous avons travaillé à développer une méthode qui vise à éliminer les désavantages du transfert avec un polymère tout en permettant un transfert simple et propre de graphène sans défaut. La méthode retenue utilise un film d’or comme support pour faciliter le transfert du graphène sur gaufre de silicium. Pour augmenter l’adhésion à la gaufre de silicium, il a été nécessaire d’introduire une étape de recuit des échantillons de graphène après le transfert avec le film d’or. Le film d’or est ensuite enlevé par la gravure chimique humide, en utilisant une solution aqueuse d’iode et d’iodure de potassium, ce qui permet de produire une monocouche de graphène sur de grandes dimensions. Après une optimisation du processus complet, nos résultats du graphène transféré sur substrat de silice présentent peu des défauts selon les mesures Raman et l’absence des résidus organiques sur la surface par la topographie AFM. / Graphene is an interesting material thanks to its excellent optical, electrical and mechanical properties. Among the methods for synthesizing high quality monolayer graphene, growth by chemical vapor deposition (CVD) on a metal is one of the most effective and economical for industrial production. However, this method requires a step to transfer graphene from the growth catalytic substrate (generally copper) to the desired substrate. Several methods allow this transfer to be carried out and the most widespread methods generally involve the use of a polymer. The main advantages are simplicity and low cost. However, there are also disadvantages related to the introduction of defects or organic residue on the surface of the transferred graphene. To maintain the quality and properties of graphene after the transfer process, we have developed a method aimed at eliminating the disadvantages of a transfer with polymer. The developed method uses a gold film as a support to facilitate the transfer of graphene onto a silicon wafer. It is a simple way to produce defect-free graphene. To increase the adhesion to the silicon wafer, it was necessary to introduce a step of annealing the graphene samples after the transfer with the gold film. The gold film was then removed by wet chemical etching with an aqueous solution of iodine and potassium iodide, which makes it possible to produce a monolayer of graphene over large dimensions. After optimizing the entire process, our results of graphene transferred on silicon substrate show few defects based on Raman measurements and the absence of organic residues on the surface by AFM topography.

Für die Herstellung von immer kleiner werdenden elektronischen Bauteilen ist es notwendig, Schichten verschiedener Stoffe auf einem Substrat abzuscheiden. Dazu werden häufig Verfahren verwendet, bei denen Gase in kleine Strukturen eindringen und dort an der Oberfläche reagieren. Damit können Schichten abgeschieden werden. Bei der Gasströmung in mikroskopischen Strukturen auf einem Wafer zeigt sich ein anderes Strömungsverhalten als bei einer Gasströmung in einer makroskopischen Struktur bei Normaldruck. Dabei sind Kollisionen zwischen Gasteilchen oft vernachlässigbar, und die Kollisionen von Teilchen mit der Geometrie, in der sich das Gas befindet, überwiegen. Zur Untersuchung solcher Vorgänge ist es von Interesse, eine derartige Gasströmung und die entsprechenden Schichtabscheidungen simulieren zu können. In dieser Arbeit wurde ein Simulationsverfahren entwickelt, welches Gase im Bereich der freien Molekülströmung und deren chemische und physikalische Interaktionen an Oberflächen simulieren kann. Die Simulationen sind dabei speziell für die freie Molekülströmung optimiert und ist nicht auf viele Aspekte angewiesen, die in anderen Strömungsregimen notwendig sind. Dies geschieht mittels einer Monte-Carlo-Simulation von Teilchen, welche mittels Pfadverfolgung in einer beliebigen dreidimensionalen Geometrie simuliert werden können. Dabei kann eine große Menge an verschiedenen Wechselwirkungen von Teilchen mit den Wänden der Geometrie simuliert werden. Es erfolgten Vergleiche mit bekannten Literaturwerten, wie der Durchlasswahrscheinlichkeit eines Zylinders oder einem einzelnen ALD Schritt in einem zylinderförmigen Loch bei verschiedenen Adsorptionswahrscheinlichkeiten. Das verwendete Simulationsverfahren erlaubt eine einfache Erweiterung von Wechselwirkungen, welche an Oberflächen auftreten können. So wurde auch ein PVD Verfahren und der Einfluss eines Kollimators auf die Teilchenströmung untersucht.:Inhaltsverzeichnis Abbildungsverzeichnis Tabellenverzeichnis Abkürzungsverzeichnis Symbolverzeichnis 1 Motivation und Einführung 2 Grundlagen 2.1 Knudsenzahl 2.1.1 Strömungsregime 2.1.2 Mittlere freie Weglänge bei verschiedenen Teilchenarten 2.2 Schichtabscheidungen 2.2.1 Chemische Gasphasenabscheidung 2.2.2 Atomlagenabscheidung 2.2.3 Physikalische Gasphasenabscheidung 2.3 Chemische Reaktionen an Oberflächen 2.3.1 Adsorption an einer freien Oberfläche 2.4 Simulationsansätze 2.4.1 Direct Simulation Monte Carlo 2.4.2 Angular Coefficient Method 2.4.3 Pfadverfolgung von Teilchen 2.4.4 Finite Volumen Methoden 3 Modellentwicklung 3.1 Grundidee 3.2 Interaktionen an Wänden 3.2.1 Reflexion und Reemission von Teilchen 3.2.2 Chemische Reaktionen 3.2.3 Tabellierte Oberflächeninteraktionen 3.3 Erweiterung für Bereiche geringerer Knudsenzahlen 3.4 Implementation 3.4.1 Wandkollisionen 3.4.2 Raytracing und Unterteilung der Geometrie 3.4.3 Simulationsdefinition 3.4.4 Simulationen in 2D 4 Simulationen und Ergebnisse 4.1 Durchlasswahrscheinlichkeit eines Hohlzylinders 4.2 Durchlasswahrscheinlichkeit durch ein gekrümmtes Rohr in 2D 4.3 ALD in einem zylinderförmigen Loch 4.4 Gleichgewicht zwischen Adsorption und Desorption an einer Oberfläche 4.5 Sputterabscheidung von Kupfer in einem PVD-Reaktor 4.5.1 Simulationen in einem Vakuum 4.5.2 Simulation bei Verwendung eines Hintergrundgases 5 Zusammenfassung und Ausblick 5.1 Zusammenfassung 5.2 Ausblick Literaturverzeichnis Danksagung Selbstständigkeitserklärung

This thesis is aimed at preparation of thin plasma-polymerized films deposited on glass fibers by Plasma-Enhanced Chemical Vapor Deposition (PE CVD) from a mixture of tetravinylsilane (TVS) and oxygen gas. Plasma-polymerized films which were deposited on silicon wafers were used to characterize chemical properties and optimization of deposition process with respect to reproducibility.

Poly-p-xylylene is a basic polymer of parylene family. It was discovered in 50s of the 20th century. In practical applications, there are used several derivates. Most of them are discussed in this thesis. Poly-p-xylylene has many utility properties, like barrier, thermal and mechanical properties. It can be used for conservation and protection of electronic equipments, medical tools and devices or museum exhibits. The most important property of parylene is its low dielectric constant which enables parylene to have good insulating properties in form of very thin layer. The most common precursor used for parylene coatings by Chemical Vapor Deposition (CVD) is [2,2]paracyclophane. Special device invented for this process was described in this thesis, including every part and assembly. The main aim of this thesis was to test properties of thin parylene layers on metal samples. High degree of polymer crystallinity was confirmed by confocal laser microscopy and optical microscopy in the polarized light measurements. Problems in the conventional method of production of parylene layers were found during the measurement of thickness of layers. Purity of deposited films was determined using Infrared spectroscopy (IR). Parylene barrier properties were quantified by the measurement of Oxygen Transmission Rate through a layer deposited on the surface of PP foil. Because the research has been mainly focused on protection of museum exhibits, the corrosion resistance test is the most important. Metal samples with thin parylene film were compared to samples with conventional restoration coating. The samples with parylene protection were slowly corroded by point corrosion. In contrast to them, the samples conserved by conventional restoration method were almost destroyed by corrosion.

Theoretical part of this master thesis was focused on literature recherché dealing with the formation of thin films, plasma, plasma analyses using mass spectrometry and plasma polymerization. Further, this section describes the analysis of thin films using optical methods such as spectroscopic ellipsometry and FT-IR spectrometry. Experimental part describes the materials which are used for the preparation of thin films as well as a description of the equipment for preparation of thin films using a technology of plasma-enhanced chemical vapor deposition (PE-CVD). Control of deposition conditions and monitoring of plasma with its products result in high reproducibility of thin films. The last part of the thesis describes the results of measurement of the first group of samples and their ellipsometric, mass spectrometry and FT-IR evaluation with respect to the deposition conditions.

This diploma thesis is mainly focused on the fabrication of graphene layers on the copper foil by the Chemical Vapor Deposition (CVD). For this purpose the high-temperature chamber for the production of the graphene was completed and fully automated. The production of the high area graphene on the copper foil was experimentally achieved. The Raman microscopy and X-ray photoelectron spectroscopy measurements proved that the produced graphene is mostly a monolayer. Graphene layer was transferred on non-conductive substrate.