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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Transjugular Intrahepatic Portosystemic Shunt (Tips), Duration of Procedural Time and Correlation with Early Morbidity and Mortality

Barrera Gutierrez, Juan Carlos 13 August 2021 (has links)
No description available.
82

Mikroohybové optovláknové snímače / Microbending fiber optic sensors

Švestka, Jiří January 2013 (has links)
This thesis deals with the influence microbending the transmitted signal at the bare optical fiber. Microbending influence on the transmitted signal is investigated in this work by changing the weight, power and water level in the tank by using this test fixture. The results of the experiments are proposed to enter the laboratory tasks to measure the impact microbending the transmitted signal in the subject line fiber-optic sensors (MOES).
83

Ultraschall-basierte Elastographie bei dekompensierter Leberzirrhose zur Charakterisierung und Prognosebewertung bei Patienten mit Indikation zur Anlage eines transjugulären intrahepatischen portosystemischen Shunts (TIPS)

Gnatzy, Franziska 05 March 2021 (has links)
No description available.
84

INTEGRATED VACUUM TRANSISTORS AND FIELD EMITTER ARRAYS

Shabnam Ghotbi (14034600) 16 June 2023 (has links)
<p>   The arrival of Si transistors and integrated circuit technology more than half a century ago made vacuum electronic technology almost extinct. Today, there are only a few niche applications for vacuum electronics. The main issues with this technology are its high voltage requirement and high-power consumption, difficult and costly fabrication technology, lack of integration capability, and poor reliability characteristics. Some of these issues may be addressed by going to nm scale fabrication that did not exist 60 years ago. Other problems such as reliability and lack of integration capability require alternative solutions to what has been proposed so far. Vacuum is the ultimate conduction media allowing electrons to reach the speed of light without any scattering. Consequently, a vacuum transistor, if designed correctly, can achieve THz frequency performance, while delivering Watt-level powers. No semiconductor technology can compete with vacuum technology to deliver such performance. </p> <p>In this work, novel methods for implementing nanoscale field emitter arrays used in vacuum electronics are proposed. Gated and ungated field emitters are fabricated with self-assembly technology and electron beam lithography. Different anisotropic dry etching recipes are developed to achieve emitters with different sharpness and aspect ratios. Our methods lead to field emitter array operation under low voltages (less than 20 V) and high current densities (around 50 A/cm2) using self-assembly and soft film anode-cathode isolator, and field emitter devices with ~4.5 A/cm2 current density with a turn-on voltage less than 50 V using electron beam lithography and oxide anode-cathode isolator. </p> <p>Making reliable field emitter devices is challenging. Due to Joule heating, ion bombardment, and geometrical variations for each tip in the field emitter arrays, emission current becomes nonuniform across the array. Sharper tips emit at a higher rate and eventually, the heat generated at the tip deforms the tips leading to electron emission at a lower rate. With ultra-low doped emitters, the current of each tip is limited to a few nano-amperes leading to a negligible current fluctuation at the tips. </p> <p>Our fabricated ultra-low doped devices with both self-assembly and electron beam lithography techniques presented constant emission current with almost no change over 24 hours of continuous operation. Such excellent reliability characteristics in vacuum field emitter devices have not been demonstrated to date.</p> <p>The screening effect in close-packed field emitter arrays which occurs by nearby conductive or semiconductive objects is thoroughly investigated and different solutions are proposed to reduce this effect between the emitters. Simulation studies using Sentaurus TCAD, MATLAB, and COMSOL Multiphysics simulators facilitated the design and optimization of gated and ungated field emitter arrays. These studies included the effect of sharpness, the distance between neighboring emitters, enclosing the emitters by a Si block around the emitters as well as anode-cathode separation on the electrical characterization of field emitter arrays. </p> <p>The optimum location and operating voltages which lead to a maximum gate control and emitter current density are also studied for gated field emitter arrays. Instead of individually gating each field emitter, it was found that controlling the emission of a sub-array with a metallic all-around gate is more efficient and it leads to higher current densities. Guided by simulations, gated field emitter arrays with 5×5 and 2×2 sub-arrays are developed. In terms of strength of the grid control (transconductance), turn-on voltage, maximum emission current, and field intensification factor, the device with the 2×2 sub-array was superior to the one with the 5×5 sub-array. The VFET with 5×5 sub-arrays achieved a higher current density due to a larger number of field emitters packed per active emission area. Finally, plans to further improve the technology and transitioning into the fabrication of vacuum integrated circuits are discussed.</p> <p>  </p>
85

Fibre orientation structures and their effects on crack resistance of injection moulded transverse ribbed plate

Coates, Philip D., Caton-Rose, Philip D., Duckett, R.A., Hine, P.J. January 2004 (has links)
No / An extensive study of the fibre orientation structures developed in a transverse ribbed plate during injection moulding, and the use of these structures to investigate the effect of local fibre orientation state on crack initiation resistance, is reported. The fibre orientation results for the ribbed plate, measured using large area image analysis system developed at Leeds University, showed that after an initial settling down period, the central core region, where the fibres are aligned perpendicular to the flow direction, decreased in size monotonically, with an associated monotonic increase in the outer shell regions, where the fibres are aligned preferentially along the injection direction. Interestingly, the level of orientation in the two regions remained almost constant: only the proportions of the two regions were found to change with flow length. Across the plate, close to the gate, the central core region was found to have a lens-like shape, while at the other end of the plate the core was thinner and also consistent in thickness across the sample width. The transverse rib was found to cause little disturbance to the fibre orientation of the base plate. The different proportions of the shell and core regions at different locations over the ribbed plate provided an ideal case to test the proposition of Friedrich that the crack resistance of a short fibre reinforced material depends on the number of fibres that are perpendicular to the crack tip. The impact test results gathered in this way confirmed this hypothesis of Friedrich.
86

Análise de canabinóides e cocaínicos em amostras de cabelo e sua correlação com sintomas psiquiátricos / Analysis of cannabinoids and cocainics in hair samples and correlation with psychiatric symptoms

Alves, Marcela Nogueira Rabelo 08 July 2015 (has links)
O consumo dos diferentes tipos de drogas está associado a problemas sociais, econômicos e de saúde pública, em todas as regiões no mundo. Dentre os problemas de saúde pública, podemos destacar a alta prevalência de comorbidade entre o uso de drogas e os transtornos mentais. A Cannabis, a cocaína e o crack são as drogas ilícitas mais consumidas no Brasil. A utilização do cabelo como matriz biológica para determinação destas drogas permite avaliar o uso crônicos pelos indivíduos, uma vez que o cabelo é uma matriz estável, de fácil manipulação e a janela de detecção depende apenas do comprimento do cabelo. Entretanto, a análise em cabelo ainda representa um desafio analítico. Foram desenvolvidos dois métodos para a detecção das diferentes drogas no cabelo, com diferentes enfoques analíticos. O primeiro método (desenvolvido durante o estágio de doutorado sanduíche na Itália) identificou e quantificou cocaína e metabólitos usando a técnica de column switching e detecção por LC-MS/MS. O segundo método foi desenvolvido para determinação de canabinóides nas amostras de cabelo utilizando GC-MS. O diferencial deste método foi a utilização de um novo dispositivo de extração em fase sólida (as ponteiras DPX) para concentração e purificação do extrato, utilizando menor quantidade de solventes. A determinação dos canabinóides e cocaínicos foi realizada nas amostras de cabelo da população atendida no CAPS - AD de Ribeirão Preto, São Paulo. Além da coleta da amostra de cabelo, o sujeito foi submetido a uma entrevista, onde os seguintes instrumentos de avaliação foram aplicadas: Questionário sobre a saúde do Paciente 9, Inventário de fobia social, Self Report Questionnaire, Questionário de Ansiedade de Beck, Inventário de Depressão de Beck e Questionário sobre o uso da Cannabis, bem como um questionário elaborado pelo pesquisador para coleta de dados sociodemográficos, consumo de substâncias e dados sobre a amostra de cabelo, como comprimento, cor, tintura ou coloração. As amostras de cabelo foram analisadas e a média das concentrações de cada droga encontrada no cabelo foi correlacionada com os indicadores clínicos de transtorno mentais, obtidos através dos instrumentos de avaliação psiquiátrica. A maior prevalência de indicadores clínicos positivos para transtornos psiquiátricos entre a população estudada foi de transtornos mentais comuns, entre eles a ansiedade e depressão. A comparação da média de concentração de Cannabis, cocaína e crack no cabelo com os indicadores clínicos positivos para os transtornos não apresentou resultados estatisticamente significantes. Entretanto, podemos inferir que os sujeitos que apresentaram maior concentração média de Cannabis e cocaína no cabelo possuíam mais indicadores clínicos positivos para sintomas mentais comuns e depressão maior enquanto que os sujeitos usuários de crack possuíam mais indicadores clínicos positivos para sintomas ansiedade. Apesar de algumas limitações, podemos concluir que o estudo possibilitou estimar a prevalência da morbidade entre abuso de drogas ilícitas e transtornos psiquiátricos na população atendida no Centro de Atenção Psicossocial Álcool e drogas de Ribeirão Preto. / Different kinds of drug use have been associated to social, economic and health public problems worldwide. Among the high prevalent public health problems is the comorbidity between drug abuse and psychiatric disorders. Cannabis, cocaine and crack are the most consumed illicit drugs in Brazil. Hair use as the biological matrix for the determination of these drugs allows to evaluate chronic use, once hair is a stable matrix, easy to manipulate and the window detection only depends on the size of the hair. However, hair analysis still represents an analytical challenge. It was developed two methods for the detection of the drugs in hair, with different analytical approach. The first method (developed during doctoral stage in Italy) had identified and quantified cocaine and metabolites using column switching technique and LCMS/ MS detection. The second method was developed for determination of cannabinoids in hair samples using GC-MS. Decontamination procedure was the same cited above. The differential of this method was the use of a new device in solid phase extraction (DPX tips) for the extracts concentration and purification, using less solvents volumes. Cannabinoids and cocaine analysis were performed in hair samples from people who were enrolled in the CAPS - AD of Ribeirão Preto, São Paulo. Besides hair collection, the individual was submitted to an interview, where it was applied the following evaluation scales: Patient health questionnaire - 9, Social phobia inventory, Self report questionnaire, Beck anxiety inventory, Beck depression inventory and Cannabis research questionnaire as well as a questionnaire made by the author to collect sociodemographic data, substance consume and hair data. Hair samples were analyzed and the concentrations were correlated with positive clinical factors of mental disorders obtained through evaluation scales. The highest prevalence of positive clinical indicators for psychiatric disorders among the population studied was of common mental disorders, including anxiety and depression. The comparison of the average concentration of Cannabis, cocaine and crack in the hair with the positive clinical indicators for the disorders did not show statistically significant results. However, we can infer that the subjects who had higher average concentration of Cannabis and cocaine in hair had showed positive indicators for common mental symptoms and major depression as well as the subjects who had higher average concentration of crack in hair had showed positive indicators for anxiety. Despite of some limitations, we can conclude that the study had allowed estimating the prevalence of morbidity among illicit drugs abuse and psychiatric disorders in the population enrolled in the psychosocial care center in Ribeirão Preto.
87

Leitfaden für die barrierefreie Gestaltung von Web-Angeboten in Bibliotheken

Schwartz, Eva-Maria, Rößner, Susanne 18 March 2010 (has links) (PDF)
Das vorliegende Handbuch gibt Bibliotheksangestellten, die sich mit der Aufbereitung und Einstellung von Webinhalten befassen, einen Einblick in die Problematik „Barrierefreiheit“. Dabei wird im Speziellen auf die Belange von Bibliotheken eingegangen und in diesem Zuge Richtlinien und Gesetze vorgestellt, die eine wichtige Rolle spielen. Anschließend wird auf die Barrieren eingegangen, die im Internet entstehen können. Zudem wird gezeigt, wie man diese Barrieren verhindert oder beseitigt. Das Handbuch gibt praktische Tipps, in dem es Hilfsmittel und Quellcode-Beispiel vorstellt, die zur barrierefreien Gestaltung eingesetzt werden können.
88

Estudo da degradação de ponteiras de endoscópios utilizadas em endoscopia digestiva alta. / Study of the degradation of endoscopes tips used in upper digestive endoscopy.

ANDRADE, Antônio Augusto Fraga de. 17 April 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-17T12:25:43Z No. of bitstreams: 1 ANTÔNIO AUGUSTO FRAGA DE ANDRADE - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2871535 bytes, checksum: c0965a012ab765af77feb84c2c22a016 (MD5) / Made available in DSpace on 2018-04-17T12:25:43Z (GMT). No. of bitstreams: 1 ANTÔNIO AUGUSTO FRAGA DE ANDRADE - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2871535 bytes, checksum: c0965a012ab765af77feb84c2c22a016 (MD5) Previous issue date: 2014-12-18 / O aparelho endoscópico utilizado atualmente para estudo do trato gastro-intestinal (o video-endoscópio) é resultado de quase 200 anos de evolução tecnológica. Estes endoscópios não podem ser esterilizados pelos métodos clássicos. Por sua complexidade, o processo de limpeza e desinfecção de endoscópios não é somente uma preocupação da enfermagem, ela se tornou multidisciplinar, pois exige discussão sobre riscos físicos, biológicos e químicos, tanto para o paciente quanto para a equipe. A borracha da ponta flexível dos endoscópios é uma peça fundamental para a preservação da vedação do endoscópio e principalmente preservação do paciente. Esta borracha sofre desgaste tanto durante o exame como pelos processos de desinfecção do equipamento que acabam agredindo a superfície do material. O seu desgaste ou ruptura pode acarretar na queima do gerador de imagem. A troca da borracha da ponta é considerada uma manutenção parcial e deve sempre ser executada periodicamente. Baseado no exposto este trabalho teve como objetivo principal estudar e avaliar a degradação ocorrida em ponteiras flexíveis de endoscópios digestivos submetidos a procedimentos médicos. Como resultados pode-se verificar nas microscopia, tanto ótica como eletrônica, morfologia rugosa com presença de poros para a ponteira virgem, nas ponteiras utilizadas por diferentes períodos de tempo verificou-se intensificação destas rugosidades. Por DRX pode-se observar um perfil praticamente amorfo típico de elastômero, além de identificar a presença de compostos de carga no polímero. Por FTIR pode-se comprovar diferentes estruturas para as amostras estudadas, levando a crer que algumas possuem polidimetilsiloxana em excesso com relação ao fluorelastômero. Por EDS pode-se verificar a exteriorização de compostos presentes no interior do elastômero após o período de degradação. No ensaio de tração foi verificada diminuição das propriedades físicas do elastômero devido a degradação ocorrida. No ensaio de ângulo de molhabilidade verificou-se que mesmo após o processo de degradação todas as amostras ainda apresentavam-se hidrofóbicas. Em síntese, este trabalho observou a necessidade de se desenvolver um material específico para utilização como ponteiras de endoscópios, já que os existentes no mercado aparentemente não tem destino especifico para aplicações biológicas. Ou seja, mesmo em sua forma virgem o elastômero em questão já apresenta fatores que não tornam sua utilização em meio biológico tão viável. / The endoscopic device currently used to study the gastrointestinal tract (the videoendoscope) is the result of nearly 200 years of technological evolution. These endoscopes can not be sterilized by the classical methods. Due to its complexity, the process of cleaning and disinfection of endoscopes is not only a concern of nursing, she became multidisciplinary, since it requires discussion of physical, biological and chemical hazards, both for the patient and for the team. The flexible rubber tip of the endoscope is a key piece to preserve the seal of the endoscope and especially preservation of the patient. This rubber wears out both during the test as the disinfection of equipment that processes attacking the end surface of the material. Your wear or breakage may result in the image generator burns. The replacement of the rubber tip is considered a partial maintenance and must always be performed periodically. Based on the above this work aimed to study and evaluate the degradation occurred in flexible tips of digestive endoscopes undergoing medical procedures. The results can be seen in microscopy, both optical and electronic, rough morphology with the presence of pores to the virgin tip, the tips used for different periods of time there was intensification of these ridges. XRD can observe typical listing a substantially amorphous elastomer, and identify the presence of compounds in the polymer charge. FTIR can prove different structures for the studied samples, leading to the belief that some have polydimethylsiloxane in excess with respect to the fluoroelastomer. EDS can verify the externalization of compounds within the elastomer after the degradation period. In the tensile test was observed decrease in physical properties of the elastomer due to degradation occurred. On test wetting angle was found that even after the degradation process all the samples still had become hydrophobic. In summary, this study observed the need to develop a specific material for use as tips of endoscopes, since on the market apparently has no specific target for biological applications. That is, even in its virgin form the elastomer in question already has factors that do not make their use in biological environment as possible.
89

Análise de canabinóides e cocaínicos em amostras de cabelo e sua correlação com sintomas psiquiátricos / Analysis of cannabinoids and cocainics in hair samples and correlation with psychiatric symptoms

Marcela Nogueira Rabelo Alves 08 July 2015 (has links)
O consumo dos diferentes tipos de drogas está associado a problemas sociais, econômicos e de saúde pública, em todas as regiões no mundo. Dentre os problemas de saúde pública, podemos destacar a alta prevalência de comorbidade entre o uso de drogas e os transtornos mentais. A Cannabis, a cocaína e o crack são as drogas ilícitas mais consumidas no Brasil. A utilização do cabelo como matriz biológica para determinação destas drogas permite avaliar o uso crônicos pelos indivíduos, uma vez que o cabelo é uma matriz estável, de fácil manipulação e a janela de detecção depende apenas do comprimento do cabelo. Entretanto, a análise em cabelo ainda representa um desafio analítico. Foram desenvolvidos dois métodos para a detecção das diferentes drogas no cabelo, com diferentes enfoques analíticos. O primeiro método (desenvolvido durante o estágio de doutorado sanduíche na Itália) identificou e quantificou cocaína e metabólitos usando a técnica de column switching e detecção por LC-MS/MS. O segundo método foi desenvolvido para determinação de canabinóides nas amostras de cabelo utilizando GC-MS. O diferencial deste método foi a utilização de um novo dispositivo de extração em fase sólida (as ponteiras DPX) para concentração e purificação do extrato, utilizando menor quantidade de solventes. A determinação dos canabinóides e cocaínicos foi realizada nas amostras de cabelo da população atendida no CAPS - AD de Ribeirão Preto, São Paulo. Além da coleta da amostra de cabelo, o sujeito foi submetido a uma entrevista, onde os seguintes instrumentos de avaliação foram aplicadas: Questionário sobre a saúde do Paciente 9, Inventário de fobia social, Self Report Questionnaire, Questionário de Ansiedade de Beck, Inventário de Depressão de Beck e Questionário sobre o uso da Cannabis, bem como um questionário elaborado pelo pesquisador para coleta de dados sociodemográficos, consumo de substâncias e dados sobre a amostra de cabelo, como comprimento, cor, tintura ou coloração. As amostras de cabelo foram analisadas e a média das concentrações de cada droga encontrada no cabelo foi correlacionada com os indicadores clínicos de transtorno mentais, obtidos através dos instrumentos de avaliação psiquiátrica. A maior prevalência de indicadores clínicos positivos para transtornos psiquiátricos entre a população estudada foi de transtornos mentais comuns, entre eles a ansiedade e depressão. A comparação da média de concentração de Cannabis, cocaína e crack no cabelo com os indicadores clínicos positivos para os transtornos não apresentou resultados estatisticamente significantes. Entretanto, podemos inferir que os sujeitos que apresentaram maior concentração média de Cannabis e cocaína no cabelo possuíam mais indicadores clínicos positivos para sintomas mentais comuns e depressão maior enquanto que os sujeitos usuários de crack possuíam mais indicadores clínicos positivos para sintomas ansiedade. Apesar de algumas limitações, podemos concluir que o estudo possibilitou estimar a prevalência da morbidade entre abuso de drogas ilícitas e transtornos psiquiátricos na população atendida no Centro de Atenção Psicossocial Álcool e drogas de Ribeirão Preto. / Different kinds of drug use have been associated to social, economic and health public problems worldwide. Among the high prevalent public health problems is the comorbidity between drug abuse and psychiatric disorders. Cannabis, cocaine and crack are the most consumed illicit drugs in Brazil. Hair use as the biological matrix for the determination of these drugs allows to evaluate chronic use, once hair is a stable matrix, easy to manipulate and the window detection only depends on the size of the hair. However, hair analysis still represents an analytical challenge. It was developed two methods for the detection of the drugs in hair, with different analytical approach. The first method (developed during doctoral stage in Italy) had identified and quantified cocaine and metabolites using column switching technique and LCMS/ MS detection. The second method was developed for determination of cannabinoids in hair samples using GC-MS. Decontamination procedure was the same cited above. The differential of this method was the use of a new device in solid phase extraction (DPX tips) for the extracts concentration and purification, using less solvents volumes. Cannabinoids and cocaine analysis were performed in hair samples from people who were enrolled in the CAPS - AD of Ribeirão Preto, São Paulo. Besides hair collection, the individual was submitted to an interview, where it was applied the following evaluation scales: Patient health questionnaire - 9, Social phobia inventory, Self report questionnaire, Beck anxiety inventory, Beck depression inventory and Cannabis research questionnaire as well as a questionnaire made by the author to collect sociodemographic data, substance consume and hair data. Hair samples were analyzed and the concentrations were correlated with positive clinical factors of mental disorders obtained through evaluation scales. The highest prevalence of positive clinical indicators for psychiatric disorders among the population studied was of common mental disorders, including anxiety and depression. The comparison of the average concentration of Cannabis, cocaine and crack in the hair with the positive clinical indicators for the disorders did not show statistically significant results. However, we can infer that the subjects who had higher average concentration of Cannabis and cocaine in hair had showed positive indicators for common mental symptoms and major depression as well as the subjects who had higher average concentration of crack in hair had showed positive indicators for anxiety. Despite of some limitations, we can conclude that the study had allowed estimating the prevalence of morbidity among illicit drugs abuse and psychiatric disorders in the population enrolled in the psychosocial care center in Ribeirão Preto.
90

HED-TIE: A wafer-scale approach for fabricating hybrid electronic devices with trench isolated electrodes and its application in sensing devices

Banerjee, Sreetama 29 May 2019 (has links)
Die organisch-anorganische Hybridelektronik bietet verschiedene Möglichkeiten zur Entwicklung neuartiger Bauelemente, welche die Vorteile von organischen und anorganischen Halbleitern vereinen. Planare Bauelemente werden typischerweise mittels Schattenmasken-basierter Strukturierung hergestellt. Ein Grund hierfür ist die Empfindlichkeit organischer Halbleiter gegenüber Ultraviolettem Licht und Lösungsmitteln, welche in den Standard-Photolithographieprozessen eingesetzt werden. Die Schattenmasken-Strukturierung führt allerdings zu Bauelementen mit kleinsten Abmessungen im Mikrometerbereich. Für die Reduzierung der Kanalabmessungen von planaren organisch-anorganischen Hybridbauelementen unterhalb eines Mikrometers ist die Elektronenstrahllithographie die am häufigsten verwendete Technik. Aufgrund des hohen Kosten- und Zeitaufwandes ist es nicht möglich, diese Technik für Wafermaßstab-Herstellung in der industriellen Anwendung einzusetzen. In dieser Arbeit wird eine alternative Technologie zur Herstellung von planaren Bauelementen mit isolierten Grabenelektroden und Kanalabmessungen von wenigen Hundert Nanometer bis unter 100 nm vorgestellt. Gräben kleiner als ein Mirkometer werden zunächst auf Silizium-Substraten strukturiert und anschließend mit einer isolierenden SiO2 Schicht aufgefüllt. Diese hilft dabei die gewünschten Elektrodenabstände, also die gewünschte Kanallänge, zu erreichen. Die Flexibilität des neuen Herstellungsverfahrens ermöglicht es nicht nur verschiedenen Kanallängen und Bauelement-Geometrie, sondern auch die Verwendung verschiedener Materialien für Elektroden und organischen Kanäle. Dies wiederum ermöglicht eine Vielfalt von potentiellen Anwendungen der hybriden Bauelemente. In dieser Arbeit wurde 6,13-bis (triisopropylsilylethinyl)-Pentacen (TIPS-Pentacen) Lösung und metallfreie Phthalocyanin als organisches Material verwendet und als Elektrodenmaterial diente Gold. Die entstandenen auf TIPS-Pentacen-Lösung basierenden planaren hybriden Bauelemente wurden für potentielle Anwendungen als optische sowie magnetoresistive Sensoren getestet.:Table of Contents Bibliografische Beschreibung 1 Chapter 1. Introduction 3 1.1 Organic-inorganic hybrid electronics 4 1.2 Inorganic semiconductors versus organic semiconductors 5 1.3 Electronic properties of a molecular layer 5 1.4 Vertical HEDs and planar HEDs 6 Chapter 2. Wafer-scale fabrication approach for planar HED-TIEs 8 2.1 Overview of nano-patterning techniques 8 (a) Electron beam lithography (EBL) 8 (b) Nanostencil lithography (NSL) 8 (c) Nanoimprint lithography (NIL) 9 2.2 Fabrication of planar organic-inorganic HED-TIEs 12 2.2.1 Trench refill approach for fabricating HED-TIEs 12 2.2.1.1 Deposition of the trench refill layer 15 2.2.1.2 Deposition of the organic channel material 16 (a) HED-TIE with thermally evaporated organic channel 16 (b) HED-TIE with solution processed organic channel 18 2.2.2 Spacer approach for fabricating HED-TIEs 21 2.2.2.1 Deposition of the isolation layer 23 2.3 Characterization techniques 26 (a) Electrical characterization 26 (b) Raman spectroscopy 26 (c) Photoluminescence spectroscopy 27 2.4 Summary and outlook 27 Chapter 3. Electrical characterization of HED-TIEs 29 3.1 Theoretical background 29 3.1.1 Space charge limited current (SCLC) conduction mechanism 29 3.2 Experimental details 32 3.3 Results and discussions 34 3.4 Summary and outlook 40 Chapter 4. Application of HED-TIEs as optical sensors 41 4.1 Photosensing properties of TIPS-pentacene based HED-TIEs 41 4.1.1 Theoretical background 41 4.1.2 Experimental details 43 4.1.3 Results and discussions 44 4.1.4 Summary and outlook 49 4.2 Photosensing properties of TIPS-pentacene based HED-TIEs with Au nanoparticles in the channel matrix 50 4.2.1 Theoretical background 50 4.2.2 Experimental details 51 4.2.3 Results and discussions 52 4.2.4 Summary and outlook 59 Chapter 5. Application of HED-TIE devices as magnetoresistive sensors 61 5.1 Theoretical background 61 5.1.1 Organic spintronics 61 5.1.2 Mechanisms of organic magnetoresistance (OMAR) 65 (a) Bipolaron model 68 (b) Electron-hole (e-h) pair model 69 (c) Exciton–charge interaction model 70 5.2. OMAR measurements on TIPS-pentacene OFETs and HED-TIEs 71 5.2.1 Experimental details 71 5.3 Results and discussions 73 5.4 Summary and outlook 79 Chapter 6. Summary and outlook 81 References 86 List of Figures 97 List of Tables 103 List of Abbreviations 104 Acknowledgements 106 List of Publications 108 List of Conference Presentations and Posters 109 Selbstständigkeitserklärung 111 Curriculum Vitae 112

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