In this work, new small deflection magnetic actuators have been proposed, designed, and tested for applications in Surface Enhanced Raman Scattering optical sensors. Despite the fact that SERS sensors have been shown to increase Raman over ten orders of magnitude for molecular detection, several technological challenges have prevented the design of practical sensors, such as making SERS sensors that can efficiently detect a wide variety of molecules. Since the optimum signal-to-noise in SERS occurs at different excitation wavelengths for different molecules, individual metal nanostructures need to be designed and fabricated for each independent chemical species. One possible solution to this problem is to tune the plasmon resonance frequency of the metal nanoparticles to eliminate the need for individually optimized particles. In order to achieve a tunable local dielectric environment, and thus allow for control over the resonance frequency of metal nanoparticles, a new SERS sensor geometry is proposed and a large deflection magnetic actuator is fabricated and tested as a starting point for the design of a small deflection magnetic actuator. Using the newly developed SERS geometry and the optimized fabrication processing techniques, two small deflection magnetic actuator beam structures were designed, fabricated, and tested. These devices utilizes an off-chip electromagnet source able to produce a magnetic force of approximately 14 μN on the on-chip nickel film generating deflections up to 139 nm for the straight beam device and 164 nm for the curved beam device. iii In the process of characterizing the newly developed small deflection magnetic actuator, an integrated magnetic actuator with electrostatic restoration geometry was conceived. This device was designed to meet the specifications of the small deflection magnetic actuator as well as eliminate the need of an off-chip magnetic source and fully integrate the process atop the metal nanoparticle arrays. Using adhesive iron based magnetic strips as the magnetic drive source, circular NiFe beams with 1, 2, 3, and 4 mm diameters were designed and simulated. Calculations predicted maximum achievable actuation of up to 2.5 μm. Processing steps were laid out for a set of integrated devices as a possible predecessor to the newly designed small deflection magnetic actuator.

This study concentrates on two of the main processes involved in the fabrication of electrostatic valve assembly, thick resist photolithography and wet chemical etching of a polyamide film. The electrostatic valve has different orifice diameters of 25, 50, 75 and 100 µm. These orifice holes are to be etched in the silicon wafer with deep reactive ion etching. The photolithography process is developed to build a mask of 15 µm thick resist pattern on silicon wafer. This photo layer acts as a mask for deep reactive ion etching. Wet chemical etching process is developed to etch kapton polyamide film. This etched film is used as a stand off, gap between two electrodes of the electrostatic valve assembly. The criterion is to develop the processed using standard industry tools. Pre post etch effects, such as, surface roughness, etching pattern, critical dimensions on the samples are measured with Veeco profilometer.

Revealing the prior austenite grain boundaries from a martensitic structure is well known to be very difficult and dependent on the chemical composition and the thermomechanical processing of the steel. In the present study, four different chemical etching reagents and additional thermal etching have been conducted for thermomechanical simulated tool steels Orvar Supreme and Stavax ESR. The etching results have been characterized using light optical microscopy and electron backscattered diffraction. The obtained results show that saturated aqueous picric acid, oxalic and sodium bisulfite based acid reveals prior austenite grain boundaries well for Orvar Supreme. For Stavax ESR, only aqueous CrO3-NaOH-picric acid provides good results in revealing the prior austenite grain boundaries. Thermal etching shows good potential and if conducted properly, thermal etching is a good alternative to the chemical reagents from a health- and environmental perspective.

Semiconductor quantum dots (QDs) are prime candidates for single and entangled photon sources in quantum information technologies due to their unique optical properties. This thesis investigates the development of QD sources operating at the telecom C-band ---around 1550 nm---, a critical aspect for long-distance applications in optical fibers. The research focuses on the design and optimization of InAs/GaAs QDs for efficient single photon emission within the telecom C-band. This thesis delves into the optimization of the quantum dot environment, by etching its matrix as a microlens (ML). The design process utilizes both simulations and lab fabrication techniques to achieve a source with high single photon throughput, a key requirement for quantum key distribution (QKD). To achieve this, the design optimizes factors such as material growth techniques, device structures, and microlens array configuration to enhance light collection efficiency by a microscope objective and Purcell effect for higher single-photon emission rate. The optimized microlens geometries, particularly the Gaussian and hemispherical shapes, significantly enhanced light extraction efficiency by the objective, achieving up to 40\% and 35\% respectively. The combined fabrication techniques of FIB milling, photolithography, and dry etching resulted in upgraded optical properties and minimal scattering in the microlenses. Furthermore, this work builds upon previous research conducted at the Royal Institute of Technology (KTH). The Quantum Nano Photonics (QNP) group successfully employed QDs to generate entangled photon states. This thesis extends this research by focusing on the design and optimization of a telecom C-band QD source suitable for long-distance transmission through existing fiber optic infrastructure over the Greater Stockholm Metropolitan Area, i.e. between the QNP-group lab at KTH AlbaNova campus and Ericsson HQ, in Kista, Stockholm. The feasibility of such transmission is explored by demonstrating the transmission of single photons from a QD source in the QNP lab at KTH to Ericsson's lab. This thesis contributes to the advancement of QD-based telecom C-band photon sources for future quantum communication networks, with a specific focus on microlens design and fabrication for enhanced single-photon emission efficiency. / Halvledarkvantprickar (QD) är utmärkta kandidater för enstaka och sammanflätade fotonkällor i kvantinformationsteknik på grund av deras unika optiska egenskaper. Denna avhandling undersöker utvecklingen av QD-källor som strålar på telekom C-band ---cirka 1550 nm---, en kritisk aspekt för långdistansapplikationer i optiska fiber. Forskningen fokuserar på design och optimering av InAs/GaAs QDs för effektiv emission av enstaka fotoner inom telekom C-bandet. Denna avhandling fördjupar sig i utformningen av kvantprickarkällan, med hjälp av en mikrolins (ML) array. Designprocessen använder både simuleringar och tillverkningstekniker för att uppnå en källa med hög enfotonrenhet, ett viktigt krav för kvantnyckeldistribution (QKD). För att uppnå detta optimerar designen faktorer som materialtillväxttekniker, enhetsstrukturer och mikrolinskonfiguration för att förbättra ljusinsamlingseffektiviteten och Purcell-effekten för ljusare och snabbare emission av enstaka fotoner. De optimerade mikrolinsgeometrierna, särskilt de gaussiska och halvsfäriska formerna, förbättrade avsevärt ljusextraktionseffektiviteten och nådde upp till 40\% respektive 35\%. De kombinerade tillverkningsteknikerna FIB-fräsning, fotolitografi och torretsning resulterade i uppgraderade optiska egenskaper och minimal spridning i de mikrolinserna. Vidare bygger detta arbete på tidigare forskning som bedrivits vid Kungliga Tekniska Högskolan (KTH). Quantum Nano Photonics-gruppen (QNP) använde framgångsrikt QD för att generera sammanflätade fotontillstånd. Denna avhandling utvidgar denna forskning genom att fokusera på design och optimering av en telekom C-band QD-källa lämplig för långdistansöverföring genom befintlig fiberoptisk infrastruktur över Storstockholmsområdet, dvs. mellan QNP-gruppens labb på KTH AlbaNova campus och Ericssons huvudkontor i Kista, Stockholm. Genomförbarheten av sådan överföring undersöks genom att demonstrera överföringen av enstaka fotoner från en QD-källa i QNP-labbet på KTH till Ericssons labb. Denna avhandling bidrar till utvecklingen av QD-baserade C-bandsfotonkällor för framtida kvantkommunikationsnätverk, med ett specifikt fokus på mikrolinsarraydesign för förbättrad renhet och emissionseffektivitet för enskilda fotoner. Arbetet bygger på tidigare forskning om generering av kvantsammanflätning och banar väg för säkra kvantkommunikationsnätverk över långa avstånd.

Photonic crystals (PhCs) are structures periodic in thedielectric constant. They exhibit a photonic bandgap, i.e., arange of wavelengths for which light propagation is forbidden.Engineering of defects in the PhC lattice offers new ways toconfine and guide light. PhCs have been manufactured usingsemiconductors and other material technologies. This thesisfocuses on two-dimensional PhCs etched in InP-based materials.Only recently, such structures were identified as promisingcandidates for the realization of novel and advanced functionsfor optical communication applications. The primary focus was on fabrication and characterization ofPhC structures in the InP/GaInAsP/InP material system. Thedemands on fabrication are very high: holes as small as100-300nm in diameter have to be etched at least as deep as 2µm. Thus, different etch processes had to be explored andspecifically developed for InP. We have implemented an etchingprocess based on Ar/Cl2chemically assisted ion beam etching (CAIBE), thatrepresents the state of the art PhC etching in InP. Different building blocks were manufactured using thisprocess. A transmission loss of 10dB/mm for a PhC waveguide, areflection of 96.5% for a 4-row mirror and a record qualityfactor of 310 for a 1D cavity were achieved for this materialsystem. With an etch depth of 4.5 µm, optical loss wasfound to be close to the intrinsic limit. PhC-based opticalfilters were demonstrated using (a) a Fabry-Pérot cavityinserted in a PhC waveguide and (b) a contra-directionalcoupler. Lag effect in CAIBE was utilized positively to realizehigh quality PhC taper sections. Using a PhC taper, a couplingefficiency of 70% was demonstrated from a standard ridgewaveguide to a single line defect PhC waveguide. During the course of this work, InP membrane technology wasdeveloped and a Fabry-Pérot cavity with a quality factorof 3200 was demonstrated. Keywords:photonic crystals, photonic bandgap materials,indium phosphide, dry etching, chemically assisted ion beametching, reactive ion etching, electron beam lithography,photonic integrated circuits, optical waveguides, resonantcavities, optical filtering, finite difference time domain,plane wave expansion.

<p>Photonic crystals (PhCs) are structures periodic in thedielectric constant. They exhibit a photonic bandgap, i.e., arange of wavelengths for which light propagation is forbidden.Engineering of defects in the PhC lattice offers new ways toconfine and guide light. PhCs have been manufactured usingsemiconductors and other material technologies. This thesisfocuses on two-dimensional PhCs etched in InP-based materials.Only recently, such structures were identified as promisingcandidates for the realization of novel and advanced functionsfor optical communication applications.</p><p>The primary focus was on fabrication and characterization ofPhC structures in the InP/GaInAsP/InP material system. Thedemands on fabrication are very high: holes as small as100-300nm in diameter have to be etched at least as deep as 2µm. Thus, different etch processes had to be explored andspecifically developed for InP. We have implemented an etchingprocess based on Ar/Cl₂chemically assisted ion beam etching (CAIBE), thatrepresents the state of the art PhC etching in InP.</p><p>Different building blocks were manufactured using thisprocess. A transmission loss of 10dB/mm for a PhC waveguide, areflection of 96.5% for a 4-row mirror and a record qualityfactor of 310 for a 1D cavity were achieved for this materialsystem. With an etch depth of 4.5 µm, optical loss wasfound to be close to the intrinsic limit. PhC-based opticalfilters were demonstrated using (a) a Fabry-Pérot cavityinserted in a PhC waveguide and (b) a contra-directionalcoupler. Lag effect in CAIBE was utilized positively to realizehigh quality PhC taper sections. Using a PhC taper, a couplingefficiency of 70% was demonstrated from a standard ridgewaveguide to a single line defect PhC waveguide.</p><p>During the course of this work, InP membrane technology wasdeveloped and a Fabry-Pérot cavity with a quality factorof 3200 was demonstrated.</p><p><b>Keywords:</b>photonic crystals, photonic bandgap materials,indium phosphide, dry etching, chemically assisted ion beametching, reactive ion etching, electron beam lithography,photonic integrated circuits, optical waveguides, resonantcavities, optical filtering, finite difference time domain,plane wave expansion.</p>

<p>The fabrication of zone plate lenses that are used for focusing X-rays relies on nanofabrication techniques such as e-beam lithography, reactive ion etching, and electroplating. The circular grating-like zone plate pattern can have a smallest half-period, a so-called zone width, of down to 20 nm while it also needs to have a height that is 5 to 10 times the zone width to have good diffraction efficiency. This high aspect ratio structuring is a very challenging field of nanofabrication.</p><p>This diploma project has focused on improving the process step of fabricating the electroplating mold by cryo-cooling the polymer during the reactive ion etching with O₂. The low temperature causes passivation of the sidewalls of the mold during etching which results in a more ideal rectangular profile of the high aspect ratio plating mold.</p><p>By etching at -100 °C, structures with highly vertical sidewalls and no undercut were realized. The experiments showed that there is a tradeoff between the anisotropy of the zone profile and the formation rate of polymer residue, so-called RIE grass. Through a proper choice of process parameters the grass could be completely removed without introducing any undercut.</p> / QC 20100414

Esta dissertação estuda a gravura de Carlos Oswald (1882 - 1971) tendo em vista os conceitos do próprio artista expostos em seus diversos textos, destacadamente o livro autobiográfico do autor, publicado em 1957, Como me tornei pintor, e os artigos impressos na revista Vozes de Petrópolis. O trabalho evidencia a modernidade desse artista que instala no Rio de Janeiro o ensino da gravura em metal como arte. O conceito que Oswald traz para o país sobre a gravura dista da concepção aqui vigente, visto que, ao menos, até as primeiras décadas do século XX, a gravura é considerada técnica para a reprodução de imagens, sendo arte aplicada à indústria. A fim de demonstrar o que se afirma, analisa-se documentos e textos sobre a Academia Imperial de Belas Artes e sobre o Liceu de Artes e Ofícios, ambas instituições do Rio de Janeiro. É no Liceu que Oswald implanta o ensino da gravura como obra de arte, incialmente em 1914 e, posteriormente, em 1930, sendo responsável pela formação de vários gravadores brasileiros. Nesta pesquisa, demonstra-se, ainda, que a obra gráfica de Oswald, nas duas décadas iniciais de 1900, não é analisada pela maior parte dos jornalistas que tratam das exposições de artes plásticas, o que também evidencia que a gravura não é considerada da mesma maneira que a pintura e a escultura no país. A análise das gravuras do artista é realizada, assim, a partir dessas conceituações, bem como das proposições de Oswald explicitadas em seus escritos. A análise concentra-se nas gravuras do artista pertencentes à coleção do Museu Nacional de Belas Artes/Ibram/MinC e ao acervo da Fundação Biblioteca Nacional - Brasil. / This dissertation studies the etchings of Carlos Oswald (1882-1971) in light of his own concepts disclosed in many of his texts, in particular in the autobiography entitled Como me tornei pintor, published in 1957, and in articles published in the magazine Vozes de Petrópolis. The innovativeness of the artist, who established the teaching of metal etching as art in Rio de Janeiro, is evident. With the goal of demonstrating how Oswald\'s concept of metal etching as art distanced it self from Brazil\'s first decades of the XX century firmly established conception of engraving as an art applied to the industry, an analysis of documents and texts about the Academia Imperial de Belas Artes and the Liceu de Artes e Ofícios was performed. Oswald establishes in the Liceu de Artes e Ofícios the teaching of etching as Art, being responsible for the formation of many Brazilian etchers. Here it is also demonstrated that the etchings of Carlos Oswald, during the first two decades of the 1900s, were not evaluated by most art critics for not being considered art. The analysis of the artist etching presented here is based on this above-mentioned conception, as well as in Oswald\'s own propositions expressed in his texts. The research is centered in etchings belonging to the collections of the Museu Nacional de Belas Artes/Ibram/MinC and the Fundação Biblioteca Nacional - Brasil.

Esta dissertação estuda a gravura de Carlos Oswald (1882 - 1971) tendo em vista os conceitos do próprio artista expostos em seus diversos textos, destacadamente o livro autobiográfico do autor, publicado em 1957, Como me tornei pintor, e os artigos impressos na revista Vozes de Petrópolis. O trabalho evidencia a modernidade desse artista que instala no Rio de Janeiro o ensino da gravura em metal como arte. O conceito que Oswald traz para o país sobre a gravura dista da concepção aqui vigente, visto que, ao menos, até as primeiras décadas do século XX, a gravura é considerada técnica para a reprodução de imagens, sendo arte aplicada à indústria. A fim de demonstrar o que se afirma, analisa-se documentos e textos sobre a Academia Imperial de Belas Artes e sobre o Liceu de Artes e Ofícios, ambas instituições do Rio de Janeiro. É no Liceu que Oswald implanta o ensino da gravura como obra de arte, incialmente em 1914 e, posteriormente, em 1930, sendo responsável pela formação de vários gravadores brasileiros. Nesta pesquisa, demonstra-se, ainda, que a obra gráfica de Oswald, nas duas décadas iniciais de 1900, não é analisada pela maior parte dos jornalistas que tratam das exposições de artes plásticas, o que também evidencia que a gravura não é considerada da mesma maneira que a pintura e a escultura no país. A análise das gravuras do artista é realizada, assim, a partir dessas conceituações, bem como das proposições de Oswald explicitadas em seus escritos. A análise concentra-se nas gravuras do artista pertencentes à coleção do Museu Nacional de Belas Artes/Ibram/MinC e ao acervo da Fundação Biblioteca Nacional - Brasil. / This dissertation studies the etchings of Carlos Oswald (1882-1971) in light of his own concepts disclosed in many of his texts, in particular in the autobiography entitled Como me tornei pintor, published in 1957, and in articles published in the magazine Vozes de Petrópolis. The innovativeness of the artist, who established the teaching of metal etching as art in Rio de Janeiro, is evident. With the goal of demonstrating how Oswald\'s concept of metal etching as art distanced it self from Brazil\'s first decades of the XX century firmly established conception of engraving as an art applied to the industry, an analysis of documents and texts about the Academia Imperial de Belas Artes and the Liceu de Artes e Ofícios was performed. Oswald establishes in the Liceu de Artes e Ofícios the teaching of etching as Art, being responsible for the formation of many Brazilian etchers. Here it is also demonstrated that the etchings of Carlos Oswald, during the first two decades of the 1900s, were not evaluated by most art critics for not being considered art. The analysis of the artist etching presented here is based on this above-mentioned conception, as well as in Oswald\'s own propositions expressed in his texts. The research is centered in etchings belonging to the collections of the Museu Nacional de Belas Artes/Ibram/MinC and the Fundação Biblioteca Nacional - Brasil.

Dry etching is an important technique for pattern transferin fabrication of most opto-electronic devices, since it canprovide good control of both structure size and shape even on asub-micron scale. Unfortunately, this process step may causedamage to the material which is detrimental to deviceperformance. It is therefore an objective of this thesis todevelop and investigate low damage etching processes for InPbased devices. An ion beam system in combination with hydrocarbon (CH4) based chemistries is used for etching. At variousion energies and gas flows the etching is performed in twomodes, reactive ion beam etching (RIBE) and chemical assistedion beam etching (CAIBE). How these conditions affect both etchcharacteristics (e.g. etch rates and profiles, surfacemorphology and polymer formation) and etch induced damage (onoptical and electrical properties) is evaluated and discussed.Attention is also paid to the effects of typical post etchingtreatments such as annealing on the optical and electricalproperties. An important finding is the correlation betweenas-etched surface morphology and recovery/degradation inphotoluminescence upon annealing in PH3. Since this type of atmosphere is typical forcrystal regrowth (an important process step in III/Vprocessing) a positive result is imperative. A low ion energy N2/CH4/H2CAIBE process is developed which not onlysatisfies this criteria but also exhibits good etchcharacteristics. This process is used successfully in thefabrication of laser gratings. In addition to this, the abilityof the ion beam system to modify the surface morphology in acontrollable manner is exploited. By exposing such modifiedsurfaces to AsH3/PH3, a new way to vary size and density of InAs(P)islands formed on the InP surfaces by the As/P exchangereaction is presented. This thesis also proposes a new etch chemistry, namelytrimethylamine ((CH3)3N or TMA), which is a more efficient methyl sourcecompared to CH4because of the low energy required to break the H3C-N bond. Since methyl radicals are needed for theetching it is presumably a better etching chemistry. A similarinvestigation as for the CH4chemistry is performed, and it is found that bothin terms of etch characteristics and etch induced damage thisnew chemistry is superior. Extremely smooth morphologies, lowetch induced damage and an almost complete recovery uponannealing can be obtained with this process. Significantly,this is also so at relatively high ion energies which allowshigher etch rates. <b>Keywords:</b>InP, dry etching, ion beam etching, RIBE,CAIBE, hydrocarbon chemistry, trimethylamine, As/P exchangereaction, morpholoy, low damage, AFM, SCM, annealing