Since C^C* cyclometalated Pt(II) complexes with N-heterocyclic carbene (NHC) ligands have been identified as potential emitter materials in organic light-emitting devices (OLEDs), very promising results regarding quantum yields, colour and stability have been presented. Herein, we report on four nitrile substituted complexes with a chelating NHC ligand (1-(4-cyanophenyl)-3-isopropyl-1H-benzo[d]imidazole or 4-(tert-butyl)-1-(4-cyanophenyl)-3-methyl-1H-imidazole) and a bidentate monoanionic auxiliary ligand (acetylacetone or dimesitoylmethane). The complexes have been fully characterized including extensive 2D NMR studies (COSY, HSQC, HMBC, NOESY, 195Pt NMR), three of them also by solid-state structures. Photophysical measurements in amorphous PMMA films and pure emitter films at room temperature reveal the impact of the mesityl groups in the auxiliary ligand, which led to a significant increase of the quantum yield, while the decay lifetimes decreased. The electron withdrawing nitrile groups shift the emission towards blue colour coordinates.

Realising Si-based electrically driven light emitters in a process technology compatible with mainstream microelectronics CMOS technology is key requirement for the implementation of low-cost Si-based optoelectronics and thus one of the big challenges of semiconductor technology. This work has focused on the development of microcavity enhanced silicon LEDs (MCLEDs), including their design, fabrication, and experimental as well as theoretical analysis. As a light emitting layer the abrupt pn-junction of a Si diode was used, which was fabricated by ion implantation of boron into n-type silicon. Such forward biased pn-junctions exhibit room-temperature EL at a wavelength of 1138 nm with a reasonably high power efficiency of 0.1%. Two MCLEDs emitting light at the resonant wavelength about 1150 nm were demonstrated: a) 1-lambda MCLED with the resonator formed by 90 nm thin metallic CoSi2 mirror at the bottom and semitransparent distributed Bragg reflector (DBR) on the top; b) 5.5-lambda MCLED with the resonator formed by high reflecting DBR at the bottom and semitransparent top DBR. Using the appoach of the 5.5-lambda MCLED with two DBRs the extraction efficiency is enhanced by about 65% compared to the silicon bulk pn-junction diode.

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Im Rahmen der vorliegenden Arbeit wurden die technologischen Ansätze zur Erzeugung von Mikro-Kavitäten als Grundlage zur Entwicklung und Erprobung neuer Konzepte der MEMS-basierten Aktoren und Sensoren erfolgreich eingesetzt. Im Verlauf der Integration eines IR-Emitters wurde der SON-Prozess weiterentwickelt, um eine hohe und homogene Verteilung der Dotierstoffe innerhalb der SON-Membran zu erreichen. Dabei wurde ein technologischer Ablauf entwickelt, welcher die genannten Randbedingungen erfüllt und darüber hinaus eine optimierte Herstellung anbietet, indem die zeitaufwändige Formierung der Kavität in einem Batch- anstatt eines RTP-Ofens erfolgt. Die Opferschichttechnik wurde bei der Integration von beiden vorgestellten Bauelementen eingesetzt und mit Rücksicht auf die einzelnen Randbedingungen angepasst. So konnte z. B. eine Kavität mit einer Höhe von 700 nm zur Abdeckung von IR-Emitter hergestellt werden, wodurch die thermische Isolation verbessert wurde. Im Konzept des druckempfindlichen Feldeffekttransistors wurde eine Opferschicht mit einer Dicke von 70 nm verwendet, um die Größe der Gate-Kapazität so anzupassen, dass der hergestellte Transistor steuerbar und druckempfindlich ist. Somit konnten die Flexibilität und das Potenzial der beiden Prozessknotenpunkte verdeutlicht werden.:Symbolverzeichnis Abkürzungsverzeichnis 1 Einleitung 1.1 Einführung zum Thema 1.2 Technologien zur Herstellung von Mikro-Kavitäten für MEMS 1.2.1 Silicon-On-Nothing Technologie 1.2.2 Opferschichttechnik 2 Das neue Konzept einer breitbandigen Infrarotquelle 2.1 Grundlegende Ideen der Infrarot-Sensorik 2.1.1 Wechselwirkung von Infrarotstrahlung mit CO2-Gas 2.1.2 Prinzipielle Funktionsweise eines IR-Emitters 2.1.3 CMOS-kompatible Materialien und Integrationsmöglichkeiten eines IR-Emitters 2.1.4 Das neue Konzept eines Infrarot-Emitter-Systems basierend auf monokristallinem Silizium 2.2 Finite-Elemente-Methode-Simulation des IR-Emitter-Systems 2.2.1 Geometrievarianten 2.2.2 Temperaturabhängige elektrische Eigenschaften des Bauelements 2.2.3 Betrachtung der thermischen Verluste 2.2.4 Simulation der Wärmeentwicklung 3 Herstellung und Charakterisierung eines IR-Emitters 3.1 Module der CMOS-basierten 3D-Integration 3.1.1 FEOL - Front End of Line 3.1.2 BEOL - Back End of Line 3.2 Elektrische Charakterisierung des IR-Emitters 3.2.1 I(V)-Spektren 3.2.2 Optische Eigenschaften 3.2.3 Zeitabhängiges Verhalten 4 Das neue Konzept eines druckempfindlichen Feldeffekttransistors 4.1 Einleitung zum Konzept des Bauelements 4.1.1 Konzepte zur Herstellung von MOSFET - basierten Sensoren 4.1.2 Prinzipieller Aufbau und Funktionsweise des neuen Konzepts 4.1.3 Geometrievarianten 5 Herstellung und Charakterisierung eines druckempfindlichen Feldeffekttransistors 5.1 CMOS-basierte 3D-Integration 5.1.1 Herstellung des MEMS-Elements: FEOL - Module 5.1.2 Herstellung des MEMS-Elements: BEOL - Module 5.2 Elektrische Charakterisierung des Feldeffekttransistors 5.2.1 Ausgangskennlinienfeld unter Normaldruck 5.2.2 Eingangskennlinien und deren Besonderheiten unter Normaldruck 5.3 Verhalten des Transistors bei veränderbarem Gasdruck 5.3.1 Designvariante I 5.3.2 Designvariante II 5.3.3 Designvariante III 5.3.4 Druckmessung mit Konstantstromquelle 5.4 Optimierung der Transistoreigenschaften 5.4.1 Anpassung des Gate-Dielektrikums und der Dotierung des Kanals 5.4.2 Ausgangskennlinien unter Normaldruck nach der Optimierung 5.4.3 Eingangskennlinien unter Normaldruck nach der Optimierung 5.4.4 Druckmessung nach der Optimierung 5.4.5 Bewertung der Prozessoptimierung anhand der Referenz-Strukturen 6 Zusammenfassung und Ausblick 6.1 Zusammenfassung zum IR-Emitter 6.2 Zusammenfassung zum Drucksensor Literatur Abbildungsverzeichnis Tabellenverzeichnis

Der Vortrag zeigt die Komplexität der Wechselwirkungen zwischen Infrarotstrahler und Werkstoff beim Infrarotschweißen von Kunststoffen auf. Hierfür werden die Haupteinflüsse auf die Strahler-Werkstoff-Wechselwirkungen beschrieben. Diese sind das Emissionsverhalten des Infrarotstrahlers und das Absorptionsverhalten des Kunststoffs. Der Einfluss der Infrarotstrahlerart (Quarzglasstrahler, Metallfolienstrahler) und von Füllstoffen (Ruß, Glasfasern) im Kunststoff wird näher betrachtet. Zudem enthält der Vortrag eine Empfehlung für die Vorgehensweise beim Infrarotschweißen von Kunststoffen, die Vor- und Nachteile des Fügeverfahrens und einen Einblick in aktuelle Forschungsaktivitäten auf dem Gebiet des Infrarotschweißens von Kunststoffen.

The thesis is focused on high temperature processes in crystalline solar cells production. Main topic is diffusion of traditional dopants phosphorus and boron. Diffusion processes for creating solar cells are different from classical diffusion in semiconductor industrial. It is reason why the thesis describes crated layers in detail. Knowledge of diffusion processes is used for creating bifacial solar cells and development of a new phosphorus emitter for conventional solar cells. Bifacial cells are a new type of cells. Developed new emitter increases efficiency and decreases cost of solar cells production. Another part the thesis is devoted to the prediction of diffusion processes. New models of phosphorus and boron diffusion for photovoltaic industrial are created in software SILVACO. Models correspond with real results.

Lyman continuum (LyC) photons are known to be responsible for reionising the universe after the end of the Dark Ages, which marked a period called the Epoch of Reionisation (EoR). While these high-energy photons are thought to predominantly originate from young, hot, massive stars within the earliest galaxies, and contributions from high-energy sources like quasars and AGN, the origins of these photons are yet not well known and highly debated. Detecting LyC photons from the early galaxies near the EoR is not possible as they get completely absorbed by the intergalactic medium (IGM) on their way to us, which has prompted the development of various indirect diagnostics to study the amount of LyC photons contributed by such galaxies by studying their analogues at low redshifts. In this study, we probe the ionised interstellar medium (ISM) of seven Green Pea galaxies through spatially resolved[O III] λ5007/[O II] λ3727 (O32) and [O III] λ5007/Hα λ6562 (O3Hα) emission-line ratio maps, using data from the Multi Unit Spectroscopic Explorer (MUSE) onboard the Very large telescope (VLT). Out of the two ratios, the former has proven to be a successful diagnostic in predicting Lyman continuum emitters (LCEs). Along with the line ratio maps, the surface brightness profiles of the galaxies are also studied to examine the spatial distribution of the emission lines and the regions from which they originate. The resulting maps indicate whether the ISM of the galaxies is ionization-bounded or density-bounded. Our analysis reveals that a subset of the galaxies with ionization-bounded ISM exhibits pronounced ionisation channels in the outer regions. These channels are potential pathways through which Lyman continuum photons may escape. For density-bounded ISM, the ionised ISM extends well beyond the stellar regions into the halos of the galaxies, highlighting their potential contribution to the ionising photon budget during the EoR. The findings emphasise the importance of spatially resolved ISM studies in understanding the mechanisms facilitating the escape of LyC photons.

La polyvalence de la réaction de couplage-croisé C-N a été explorée pour la synthèse de deux nouvelles classes de ligands: (i) des ligands bidentates neutres de type N^N et (ii) des ligands tridentates neutres de type N^N^N. Ces classes de ligands contiennent des N-hétérocycles aromatiques saturés qui sont couplés avec hexahydropyrimidopyrimidine (hpp). Les ligands forment de cycles à six chaînons sur la coordination du centre Ru(II). Ce fait est avantageux pour améliorer les propriétés photophysiques des complexes de polypyridyl de Ru(II). Les complexes de Ru(II) avec des ligands bidentés ont des émissions qui dépendent de la basicité relative des N-hétérocycles. Bien que ces complexes sont électrochimiquement et photophysiquement attrayant, le problème de la stereopurité ne peut être évité. Une conception soigneuse du type de ligand nous permet de synthétiser un ligand bis-bidentate qui est utile pour surmonter le problème de stereopurité. En raison de la spécialité du ligand bis-bidentate, son complexe diruthénium(II,II) présente une grande diastéréosélectivité sans séparation chirale. Alors que l'unité de hpp agit comme un nucléophile dans le mécanisme de C-N réaction de couplage croisé, il peut également agir en tant que groupe partant, lorsqu'il est activé avec un complexe de monoruthenium. Les complexes achiraux de Ru(II) avec les ligands tridentés présentent des meilleures propriétés photophysiques en comparason avec les prototypes [Ru(tpy)2]2+ (tpy = 2,2′: 6′, 2′′-terpyridine). L’introduction de deux unités de hpp dans les ligands tridentates rend le complexe de Ru(II) en tant que ‘absorbeur noir’ et comme ‘NIR émetteur’ (NIR = de l’anglais, Near Infra-Red). Cet effet est une conséquence d'une meilleure géométrie de coordination octaédrique autour de l'ion Ru(II) et de la forte donation sigma des unités hpp. Les complexes du Re(I) avec des ligands tridentates présentent un comportement redox intéressant et ils émettent dans le bleu. L'oxydation quasi-réversible du métal est contrôlée par la donation sigma des fragments hpp, tandis que la réduction du ligand est régie par la nature électronique du motif N-hétérocycle central du ligand lui-même. Cette thèse presente également l'auto-assemblage des métal-chromophores comme ‘métallo-ligands’ pour former des espèces supramoléculaires discretes utilisant des complexes neutres. Les synthèses et propriétés des métaux-chromophores précités et les supramolécules sont discutées. / The versatility of C-N cross coupling reactions has been explored for the synthesis of two novel classes of ligands : (i) neutral bidentate N^N ligands and (ii) neutral tridentate N^N^N ligands. Both classes of ligands contain saturated aromatic N-heterocycles coupled with the unsaturated hexahydropyrimidopyrimidine (hpp) unit. The ligands form six-membered chelate rings upon coordination to a Ru(II) center. This fact is advantageous to improve the photophysical properties of Ru(II)-polypyridyl complexes. Ru(II) complexes of bidentate ligands can act as red-emitters. The red-emission is dependent on the relative basicity of the N-heterocycles. While these complexes are electrochemically and photophysically appealing, the problem of stereopurity can not be avoided. Careful ligand design affords bis-bidentate ligand that is useful to overcome the problem of stereopurity. Due to the speciality of this bis-bidentate ligand, its diruthenium(II,II) complex exhibits high diastereoselectivity without any chiral separation. While the hpp unit acts as a nucleophile in the mechanism of C-N cross coupling reaction, it can also act as a leaving group when activated as a monoruthenium complex. Achiral Ru(II) complexes of the tridentate ligands display improved photophysical properties over the prototype complex [Ru(tpy)2]2+ (tpy = 2,2’:6’,2’’-terpyridine). Introduction of two hpp units in the tridentate ligands renders the Ru(II) complex into a ‘black absorber’ and a ‘NIR emitter’ (NIR = Near Infra-Red). This fact is a consequence of better octahedral geometry around the Ru(II) ion and strong sigma-donation from the hpp units. The blue-emitting Re(I) complexes of the tridentate ligands also exhibit interesting redox behavior. The metal-based quasi-reversible oxidation is controlled by the sigma-donation from the hpp moieties, while the ligand-based reduction is governed by the electronic nature of the central N-heterocycle of the same ligand moiety. This thesis also incorporates self-assembly of metal-chromophores as ‘metallo-ligands’ to form discrete supramolecular species using neutral metal-complexes. The syntheses and properties of the aforesaid metal-chromophores and the supramolecules are discussed.

Ocorrem anualmente aproximadamente 600.000 mortes de crianças com até cinco anos, no mundo. Pneumonia é a principal causa e mais de 50 por cento destas mortes são atribuídas à poluição do ar. Ela ainda é responsável pelo aumento do risco de infecções respiratórias, asma, condições neonatais adversas e anomalias congênitas. A poluição do ar também afeta o desenvolvimento cognitivo de crianças e induz o desenvolvimento de doenças crônicas na idade adulta. Entre 70 e 80 por cento da poluição do ar em nações em desenvolvimento são de origem veicular. Objetivando definir critérios baseados em medições com sensoriamento remoto para identificação de veículos automotores leves do ciclo Otto com elevadas emissões de monóxido de carbono, hidrocarbonetos ou óxido nítrico, foram utilizados os dados secundários gerados pela Remote Sensing do Brasil Ltda dos quais foram selecionados 179.142 veículos em uso da frota circulante da cidade de São Paulo com medições completas dos índices de emissão dos poluentes monóxido de carbono (CO), hidrocarbonetos (HC) e óxido nítrico (NO) e ainda velocidade e aceleração do veículo quando da medição e inclinação da pista no local escolhido para as medições. Foram ajustados modelos estatísticos da classe Generalised Additive Models for Location, Scale and Shape (GAMLSS) visando testar a influência do Tipo de Combustível, da Potência Específica do Veículo (VSP) e das Fases do Programa de Controle da Poluição do Ar por Veículos Automotores (Proconve) sobre as emissões de CO, HC e NO, medidos usando o Remote Sensing Device (RSD). As emissões foram então conceitualmente subdivididas em dois grupos: veículos com emissões normais e com emissões anormais, isso para os diversos poluentes em veículos das Fases L3, L4 e L5 que são as fases de interesse para o gerenciamento da qualidade do ar. Variáveis latentes foram definidas para indicarem as distribuições dos veículos em relação a esses grupos e Fases. O algoritmo Expectation-Maximization (EM) foi empregado para identificação dos parâmetros das distribuições. Para determinação dos valores associados aos veículos com elevadas emissões de determinado poluente e fase do Proconve, foi empregado o percentil 98 por cento da distribuição ajustada para os veículos dos grupos com emissões normais. Assim sendo, o Erro de Tipo I foi fixado em 2 por cento sendo que esse percentual foi estabelecido considerando o Erro de Tipo II, de apontar o veículo como tendo emissão normal quando na realidade trata-se de um high emitter. Através desta abordagem foram determinados os valores indicativos de veículos com elevadas emissões segundo o poluente e a Fase do Proconve. Os resultados apontaram decréscimo nas emissões de CO e de HC segundo as Fases do Proconve. Para o NO, o comportamento das emissões não acompanhou as reduções impostas pelas Fases do Proconve. Foi constatado que os veículos de 2005 a 2009, movidos exclusivamente a gasool, foram os que apresentaram as maiores emissões de NO. Diversos possíveis fatores causadores deste comportamento diferenciado do NO foram discutidos neste trabalho. Os dados de qualidade do ar detectaram aumento significativo nas concentrações ambientais de Óxidos de Nitrogênio (NOx) em 2007, quando foi monitorado este parâmetro no período de inverno, o que pode indicar a influência dos high emitters, mas necessita de estudos mais aprofundados para confirmação da causa deste comportamento. / Approximately 600,000 deaths occur worldwide annually for children up to five years of age. Pneumonia is the leading cause and more than 50 per cent of these deaths are attributed to air pollution. It is still responsible for increased risk of respiratory infections, asthma, adverse neonatal conditions and congenital anomalies. Air pollution also affects the cognitive development of children and induces future development of chronic diseases in adulthood. In order to define criteria based on remote sensing measurements to identify Otto cycle light duty vehicles (LDV) with high emissions of carbon monoxide, hydrocarbons or nitric oxide it was used secondary data produced by Remote Sensing do Brasil Ltda, from which 179,142 inuse vehicles were selected, that belongs to the city of São Paulos current fleet. All those vehicles had complete measurements of emission of carbon monoxide (CO), hydrocarbons (HC) and nitric oxide (NO), and also speed and acceleration of the vehicle during measurements, and slope of the track at the place chosen for the measurements. Statistical models of the Generalized Additive Models for Location, Scale and Shape (GAMLSS) class were adjusted to test the influence of fuel type, Vehicle Specific Power (VSP) and of the Brazilian Vehicle Emission Control Program [Proconve] phases on CO, HC and NO emissions, measured using Remote Sensing Device (RSD). The emissions were then conceptually subdivided into two groups: vehicles with normal and abnormal emission, for the various pollutants in vehicles of L3, L4 and L5 phases of Proconve, which were of interest for the air quality management. Latent variables were defined to indicate the distribution of vehicles in relation to those groups and phases. The algorithm Expectation Maximization (EM) was employed to identify all parameters of the distributions. We use the 98 per cent percentiles of the statistical distribution set, for vehicles of groups with normal emissions to determine the limit values for vehicles with high emissions of pollutants and Proconve Phase. Therefore, the Type I Error was set at 2 per cent and this percentage was established considering the Type II Error to point the vehicle as having normal emission when in fact it is a high emitter. Through this approach, the indicative values of vehicles with high emissions according to the pollutant and the Proconve Phase were determined. Results of emissions measured with the RSD technique indicated a decrease in CO and HC emissions according to the Proconve Phase. For the NO, the emissions behavior did not follow the reductions imposed by the Proconve Phases. It was found that newer vehicles year model from 2005 to 2009 exclusively gasohol-powered vehicles, were the ones that presented the highest NO emissions. Several possible causative factors of this differential behavior of NO were discussed in this study. A significant increase in the environmental concentrations of Nitrogen Oxides (NOx) was detected in 2007, when this parameter was monitored in the winter period. This may indicate the influence of the high emitter vehicles, but it requires a more in-depth cause-effect study for confirmation of this behavior.

In dieser Doktorarbeit werden zwei Konzepte der Quanteninformationsverarbeitung realisiert. Der Quantenschlüsselaustausch ist revolutionär, weil er perfekte Sicherheit gewährleistet. Zahlreiche Quantenkryptografieprotokolle wurden schon untersucht. Zwei Probleme bestehen. Zum einen ist es sehr schwer, die Bedingungen herzustellen, die in den Annahmen für perfekte Sicherheit impliziert sind. Zum anderen sind die Reichweiten auf momentan etwa 200 km begrenzt, aufgrund des abnehmenden Signals gegenüber des konstanten Rauschens. Ein Experiment dieser Doktorarbeit beschäftigt sich mit dem ersten Problem. Insbesondere der übertragene Quantenzustands ist kritisch für die Sicherheit des Verfahrens. Es werden Einzelphotonen von Stickstoff- Fehlstellen-Zentren und zum ersten Mal von Silizium-Fehlstellen-Zentren für einen Quantenschlüsselaustausch mit Hilfe des BB84-Protokolls benutzt. Die Abweichung von idealen Einzelphotonenzuständen sowie deren Bedeutung für die Sicherheit werden analysiert. Die Übertragung von Quantenzuständen via Satellit könnte das Problem der begrenzten Reichweite lösen. Das neue Frequenz-Zeit- Protokoll eignet sich dafür besonders gut. Es wird während dieser Arbeit zum ersten Mal überhaupt implementiert. Umfangreiche Untersuchungen inklusive der Variation wesentlicher experimenteller Parameter geben Aufschluss über die Leistungsfähigkeit und Sicherheit des Protokolls. Außerdem werden elementare Bestandteile eines vollautomatischen Experiments zum Quantenschlüsselaustausch über Glasfasern in der sogenannten Time-bin-Implementierung mit autonomem Sender und Empfänger realisiert. Ein anderes Konzept der Quanteninformationsverarbeitung ist die Herstellung zufälliger Bitfolgen durch den Quantenzufall. Zufällige Bitfolgen haben zahlreiche Anwendungsgebiete in der Kryptografie und der Informatik. Die Realisierung eines Quantenzufallszahlengenerators mit mathematisch beschreibbarer und getesteter Zufälligkeit und hoher Bitrate wird ebenfalls beschrieben. / In this thesis, photonic quantum states are used for experimental realisations of two different concepts of quantum information processing. Quantum key distribution (QKD) is revolutionary because it is the only cryptographic scheme offering unconditional security. Two major problems prevail: Firstly, matching the conditions for unconditional security is challenging, secondly, long distance communication beyond 200 km is very demanding because an increasingly attenuated quantum state starts to fail the competition with constant noise. One experiment accomplished in this thesis is concerned with the first problem. The realisation of the actual quantum state is critical. Single photon states from nitrogen and for the first time also silicon vacancy defect centres are used for a QKD transmission under the BB84 (Bennett and Brassard 1984). The deviation of the used single photon states from the ideal state is thoroughly investigated and the information an eavesdropper obtains due to this deviation is analysed. Transmitting quantum states via satellites is a potential solution to the limited achievable distances in QKD. A novel protocol particularly suited for this is implemented for the first time in this thesis, the frequency-time (FT) protocol. The protocol is thoroughly investigated by varying the experimental parameters over a wide range and by evaluating the impact on the performance and the security. Finally, big steps towards a fully automated fibre-based BB84 QKD experiment in the time-bin implementation with autonomous sender and receiver units are accomplished. Another important concept using quantum mechanical properties as a resource is a quantum random number generator (QRNG). Random numbers are used for various applications in computing and cryptography. A QRNG supplying bits with high and quantifiable randomness at a record-breaking rate is reported and the statistical properties of the random output is thoroughly tested.