Resonant Metagratings For Spectral And Angular Control Of Light For Colored Rooftop Photovoltaics,
2020
University of Amsterdam
Resonant Metagratings For Spectral And Angular Control Of Light For Colored Rooftop Photovoltaics, Floris Uleman, Andrea Cordaro, Andrea Alù, Albert Polman
Advanced Science Research Center
We designed semitransparent metagrating supercells that enable control over the spectrum and directivity of incident light for applications in photovoltaics with tailored angular appearance. The building block of the supercells is a 100–120 nm wide and 175 nm tall silicon nanowire that shows a strong Mie resonance around λ = 650 nm. By arranging the resonant Mie scatterers into metagratings of increasing pitch (675–1300 nm), we created a Lambertian-like scattering distribution over an angular range of choice. The millimeter-sized metasurfaces were fabricated using electron beam lithography and reactive ion etching. The fabricated metasurface nearly fully suppresses specular reflection on resonance …
Characterization Of Reactive Ion Etch Chemistries Using Direct Write Lithography,
2020
Air Force Institute of Technology
Characterization Of Reactive Ion Etch Chemistries Using Direct Write Lithography, Dylan T. Martin-Abood
Theses and Dissertations
The DoD requires a variety of COTS and number of custom microelectronics to provide important functionality to critical military systems. Photolithography and DRIE are two techniques commonly used in the development of deep anisotropic features for the fabrication and modification of microelectronics and MEMS. However, standard photolithography techniques are ineffective for unique substrate geometries and DRIE processes require a chemical passivation step only applicable to Si substrates. This work confirmed the capability of RIE using DWL to perform deep, highly selective, anisotropic etching on elevated, non-circular substrates.
Development Of Integrated Zinc Oxide Nanorods Coated Glass Substrate Sensing Device,
2020
Universiti Malaya
Development Of Integrated Zinc Oxide Nanorods Coated Glass Substrate Sensing Device, Mohd Yusof Haziezol Helmi
Student Works (2020-2029)
A simple and practical cost-effective integrated zinc oxide (ZnO) nanorods coated glass substrate sensing device for humidity and formaldehyde vapor sensing applications is reported. The developed sensor device is composed of a commercial light-emitting diode (LED) and photodiode that correspondingly served as light source and detector which precisely positioned on a 3D printed sensor platform. A receiver circuit and Arduino platform were employed for signal amplification and processing. A uniform ZnO nanorods coating were grown on the surface of glass substrate via hydrothermal method by controlling the growth durations and coating length. A standard reference for the optimum working condition …
Noble-Transition Alloy Absorbers For Near-Infrared Hot-Carrier Optoelectronics,
2020
Louisiana State University
Noble-Transition Alloy Absorbers For Near-Infrared Hot-Carrier Optoelectronics, Sara Karoline Figueiredo Stofela
LSU Doctoral Dissertations
Optoelectronics is the field of technology concerned with the study and application of electronic devices that source, detect and control light. Here we focus on the optical communications field which relies on optical fiber systems to carry signals to their destinations operating in the near-infrared range. To improve the performance of current optical fiber systems, one of the paths is to develop better near-infrared photodetectors.
The current group of materials used for near-infrared photodetection relies in the III-V semiconductor family. Although their spectral photosensitivity correlates well with the near-infrared, response time performance and electronic circuit integration remain limited for this …
Anti-Resonance, Inhibited Coupling And Mode Transitionin Depressed Core Fibers,
2020
Technological University Dublin
Anti-Resonance, Inhibited Coupling And Mode Transitionin Depressed Core Fibers, Xiaokang Lian, Gerald Farrell, Qiang Wu, Wei Han, Changyu Shen, Youqiao Ma, Yuliya Semenova
Articles
The depressed core fiber (DCF), consisting of a low-index solid core, a high-index cladding and air surrounding, is in effect a bridge between the conventional step-index fiber and the tube-type hollow-core fiber from the point of view of the index profile. In this paper the dispersion diagram of a DCF is obtained by solving the full-vector eigenvalue equations and analyzed using the theory of anti-resonant and the inhibited coupling mechanisms. While light propagation in tube-type hollow-core fibers is commonly described by the symmetric planar waveguide model, here we propose an asymmetric planar waveguide for the DCFs in an anti-resonant reflecting …
Fabrication, Characterization And Applications Of Highly Conductive Wet-Spun Pedot:Pss Fibers,
2020
University of Kentucky
Fabrication, Characterization And Applications Of Highly Conductive Wet-Spun Pedot:Pss Fibers, Ruben Sarabia Riquelme
Theses and Dissertations--Chemical and Materials Engineering
Smart electronic textiles cross conventional uses to include functionalities such as light emission, health monitoring, climate control, sensing, storage and conversion of energy, etc. New fibers and yarns that are electrically conductive and mechanically robust are needed as fundamental building blocks for these next generation textiles.
Conjugated polymers are promising candidates in the field of electronic textiles because they are made of earth-abundant, inexpensive elements, have good mechanical properties and flexibility, and can be processed using low-cost large-scale solution processing methods. Currently, the main method to fabricate electrically conductive fibers or yarns from conjugated polymers is the deposition of the …
Arsenic Exposure And Methylation Efficiency In Relation To Oxidative Stress In Semiconductor Workers,
2020
Old Dominion University
Arsenic Exposure And Methylation Efficiency In Relation To Oxidative Stress In Semiconductor Workers, Chih-Hong Pan, Ching-Yu Lin, Ching-Huang Lai, Hueiwang Anna Jeng
Community & Environmental Health Faculty Publications
This study examined associations between oxidative stress and arsenic (As) exposure and methylation efficiency in semiconductor workers. An As-exposed group (n = 427) and a control group (n = 91) were included. The As-exposure group (n = 427) included 149 maintenance staff members and 278 production staff members representing high As exposure and low As exposure, respectively. The control group included 91 administrative staff members with no or minimal As exposure. An occupational exposure assessment was conducted to assess personal As exposure by measuring As concentrations in urine, hair, and fingernails of the subjects. Urinary As(III), As(V), monomethylarsonic (MMA), and …
Electric Field Control Of Fixed Magnetic Skyrmions For Energy Efficient Nanomagnetic Memory,
2020
Virginia Commonwealth University
Electric Field Control Of Fixed Magnetic Skyrmions For Energy Efficient Nanomagnetic Memory, Dhritiman Bhattacharya
Theses and Dissertations
To meet the ever-growing demand of faster and smaller computers, increasing number of transistors are needed in the same chip area. Unfortunately, Silicon based transistors have almost reached their miniaturization limits mainly due to excessive heat generation. Nanomagnetic devices are one of the most promising alternatives of CMOS. In nanomagnetic devices, electron spin, instead of charge, is the information carrier. Hence, these devices are non-volatile: information can be stored in these devices without needing any external power which could enable computing architectures beyond traditional von-Neumann computing. Additionally, these devices are also expected to be more energy efficient than CMOS devices …
Investigation Of Host Nanotube Parameters For Enhancing The Performance Of Nanostructured Cds-Cdte Solar Cells,
2020
University of Kentucky
Investigation Of Host Nanotube Parameters For Enhancing The Performance Of Nanostructured Cds-Cdte Solar Cells, Deepak Kumar
Theses and Dissertations--Electrical and Computer Engineering
Numerical simulations are performed to investigate the effects of host nanotube parameters (pore diameter and pitch for different CdS coverages) and CdTe doping density on device performance in nanowire CdS/ CdTe solar cells using SCAPS-1D. This research finds the optimum values for these parameters in order to achieve the highest efficiency. Experimentally the effect of anodization voltage and fluoride ion concentration on the pore diameter and the pitch are studied for the Titania nanotubes host. It is observed that in the range of 0.3 mL to 2 mL of ammonium fluoride content, pore diameter and the pitch of the Titania …
Rapid Prototyping Of Nanostructures With Electron Beam Induced Processing,
2020
University of Kentucky
Rapid Prototyping Of Nanostructures With Electron Beam Induced Processing, Samaneh Esfandiarpour
Theses and Dissertations--Electrical and Computer Engineering
Focused electron beam induced processing (FEBIP) is a nano-scale fabrication technique that allows the direct deposition of functional materials. However, it suffers from significant drawbacks, such as high cost, low speed, unavailable precursors for many materials and low purity of deposits. Liquid-phase focused electron beam induced processes (LP-FEBIP) are being investigated due to the potential benefits over the gas phase technique. In this method, deposition or etching occurs at the interface between a substrate and a bulk liquid. In this work, electron beam induced deposition of copper nanostructures from aqueous solutions of copper sulfate is demonstrated. The addition of sulfuric …
Programming Of Floating-Gate Transistors For Nonvolatile Analog Memory Array,
2020
West Virginia University
Programming Of Floating-Gate Transistors For Nonvolatile Analog Memory Array, Haifa Abulaiha
Graduate Theses, Dissertations, and Problem Reports (ETD)
Since they were introduced, floating-gate (FG) transistors have been used as non-volatile digital memory. Recent research has shown that floating-gate transistors can be successfully used as analog memory, specifically as programmable voltage and current sources. However, their proliferation has been limited due to the complex programming procedure and the complex testing equipment. Analog applications such as field-programmable analog arrays (FPAAs) require hundreds to thousands of floating-gate transistors on a single chip which makes the programming process even more complicated and very challenging. Therefore, a simplified, compact, and low-power scheme to program FGs are necessary. This work presents an improved version …
Techno-Economic Analysis Of Diethyl Ether Production Via Catalytic Dehydration Of Ethanol,
2020
Faculty of Engineering
Techno-Economic Analysis Of Diethyl Ether Production Via Catalytic Dehydration Of Ethanol, Boonraksa Chaiapha
Chulalongkorn University Theses and Dissertations (Chula ETD)
The major source of energy comes from non-renewable fuels, which have a non-sustainability and negative impact on the environment. Thus, there is change to renewable fuels as bioethanol. Diethyl ether (DEE) is a part of bioethanol. However, the increase of electric vehicles (EV) may decrease ethanol demand for biofuel in the future. Thus, it will be interesting in adding value to ethanol via the catalytic dehydration to produce DEE by conduct techno-economic analysis. Further, there is comparison on different concentrations of ethanol (93% and 95% ethanol) that affect DEE production. For simulation part, the DEE capacity of 3,600 tons/year is …
A Hybrid Electronic Nose System Based On Metal Oxide Semiconductor Gas Sensors And Compact Paper-Pased Colorimteric Sensors For Volatile Organic Compounds Classification,
2020
Faculty of Engineering
A Hybrid Electronic Nose System Based On Metal Oxide Semiconductor Gas Sensors And Compact Paper-Pased Colorimteric Sensors For Volatile Organic Compounds Classification, Aung Khant Maw
Chulalongkorn University Theses and Dissertations (Chula ETD)
Commercial metal oxide semiconductor (MOS) sensors usually employed in electronic noses (e-noses) are well known for being low-cost, portability, and ease of use. However, these sensors can only identify a limited number of odors due to insufficient selectivity. Recent studies improved the selectivity by jointly integrating the MOS sensors with additional sensor sources. However, the published hybrid systems involved complex fabrication and measurement procedures. On the contrary, this work utilizes paper-based colorimetric sensors which are simpler and easier to use. This proposed hybrid system consists of 8 commercial metal oxide sensors and a paper-based colorimetric sensor coated with phenol red, …
A Morphable Fpga Soft Processor Using Llvm Infrastructure Targeting Low-Power Application-Specific Embedded Systems,
2020
Faculty of Engineering
A Morphable Fpga Soft Processor Using Llvm Infrastructure Targeting Low-Power Application-Specific Embedded Systems, Ehsan Ali
Chulalongkorn University Theses and Dissertations (Chula ETD)
The reconfigurable computing (RC) aims to combine the flexibility of General-Purpose Processor (GPP) with performance of Application Specific Integrated Circuits (ASIC). There are several architectures proposed since RC's inception in 1960s, but all have failed to become mainstream. The main factor preventing RC to become common practice is its requirement for implementers of algorithms (programmers) to be familiar with hardware design. In RC, a hardened processor cooperates with a dynamic reconfigurable Hardware Accelerator (HA) which is implemented on Field-Programmable Gate Array (FPGA). The HA implements crucial software kernel on hardware to increase performance and its design demands digital circuit expertise. …
On-Demand Electrically Induced Decomposition Of Thin-Film Nitrocellulose Membranes For Wearable Or Implantable Biosensor Systems,
2020
Virginia Commonwealth University
On-Demand Electrically Induced Decomposition Of Thin-Film Nitrocellulose Membranes For Wearable Or Implantable Biosensor Systems, Benjamin M. Horstmann
Theses and Dissertations
Implantable or subcutaneous biosensors used for continuous health monitoring have a limited functional lifetime requiring frequent replacement and therefore may be highly discomforting to the patient and become costly. One possible solution to this problem is use of biosensor arrays where each individual reserve sensor can be activated on-demand when the previous one becomes inoperative due to biofouling or enzyme degradation. Each reserve biosensor in the array is housed in an individual Polydimethylsiloxane (PDMS) well and is protected from exposure to bodily fluids such as interstitial fluid ( ISF) by a thin-film nitrocellulose membrane. Controlled activation is achieved by decomposing …
Synthesis Of Graphene Using Plasma Etching And Atmospheric Pressure Annealing: Process And Sensor Development,
2020
West Virginia University
Synthesis Of Graphene Using Plasma Etching And Atmospheric Pressure Annealing: Process And Sensor Development, Andrew Robert Graves
Graduate Theses, Dissertations, and Problem Reports (ETD)
Having been theorized in 1947, it was not until 2004 that graphene was first isolated. In the years since its isolation, graphene has been the subject of intense, world-wide study due to its incredibly diverse array of useful properties. Even though many billions of dollars have been spent on its development, graphene has yet to break out of the laboratory and penetrate mainstream industrial applications markets. This is because graphene faces a ‘grand challenge.’ Simply put, there is currently no method of manufacturing high-quality graphene on the industrial scale. This grand challenge looms particularly large for electronic applications where the …
The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review,
2019
Department of Water Supply and Irrigation Engineering, Water Institute, P. O. Box 35059, Dares Salaam
The Potentials Of Faecal Sludge Treatment Using Local Conditioners In Tanzania: A Review, Doglas Benjamin1
Tanzania Journal of Engineering and Technology (TJET)
Worldwide, every day human beings generate millions of tons of Faecal Sludge (FS), which is rich in water, nutrients, energy, and organic compounds. Yet FS is not being managed in a way that permits us to derive value from its reuse, while at the same time, millions of farmers struggle with depleted soils and lack of water. In most of the developing countries, energy for cooking is mainly derived from cutting of trees, either as wood or charcoal. Resource recovery and reuse from FS can create livelihoods, enhance food security, support green economies, reduce waste and contribute to cost recovery …
Reducing The Production Cost Of Semiconductor Chips Using (Parallel And Concurrent) Testing And Real-Time Monitoring,
2019
Southern Methodist University
Reducing The Production Cost Of Semiconductor Chips Using (Parallel And Concurrent) Testing And Real-Time Monitoring, Qutaiba Khasawneh
Electrical Engineering Theses and Dissertations
Consumer electronics changed the semiconductor industry by developing many new challenges for consumer products. One of the main challenges in the consumer product is that it propelled the volume of production to massive production, e.g. hundreds of millions of cell phones are produced yearly. Combined with the overproduction of consumer products, price pressure is another challenge for consumer products. Many of the new techniques used in the design and fabrication enabled the integration of more devices in the same chips. This reduced the cost of the chips, lowered the power consumption, increased the circuit operation speed, enabled more reliable implementation, …
Interfacial Contact With Noble Metal - Noble Metal And Noble Metal - 2d Semiconductor Nanostructures Enhance Optical Activity,
2019
University of Arkansas, Fayetteville
Interfacial Contact With Noble Metal - Noble Metal And Noble Metal - 2d Semiconductor Nanostructures Enhance Optical Activity, Ricardo Raphael Lopez Romo
Graduate Theses and Dissertations
Noble metal nanoparticles and two-dimensional (2D) transition metal dichalcogenide (TMD) crystals offer unique optical and electronic properties that include strong exciton binding, spin-orbital coupling, and localized surface plasmon resonance. Controlling these properties at high spatiotemporal resolution can support emerging optoelectronic coupling and enhanced optical features. Excitation dynamics of these optical properties on physicochemically bonded mono- and few-layer TMD crystals with metal nanocrystals and two overlapping spherical metal nanocrystals were examined by concurrently (i) DDA simulations and (ii) far-field optical transmission UV-vis spectroscopic measurements. Initially, a novel and scalable method to unsettle van der Waals bonds in bulk TMDs to prepare …
High Frequency Ltcc Based Planar Transformer,
2019
University of Arkansas, Fayetteville
High Frequency Ltcc Based Planar Transformer, Adithya Venkatanarayanan
Graduate Theses and Dissertations
As we move towards high power and higher frequency related technology, conventional wire-wound magnetics have their own limitations which has led path to the development of planar based magnetic materials. Nowadays more planar magnetic technology has been employed because it is easier to fabricate them. The planar magnetic is a transformer or an inductor that replaces the wire-wound transformer or inductors which generally uses copper wires. One of the main reasons why we move to planar magnetic technology is its operation at higher frequency which provides higher power density. This study explains in detail about the design and fabrication of …
