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Characterization Of An Amine-Thiol Cosolvent System : Ethylenediamine And Mercaptoethanol, Fernanda Giongo Fernandes
Characterization Of An Amine-Thiol Cosolvent System : Ethylenediamine And Mercaptoethanol, Fernanda Giongo Fernandes
Legacy Theses & Dissertations (2009 - 2024)
Since its introduction, the amine-thiol cosolvent system has been successfully utilized for the deposition of various thin-film devices, but its mechanism of action is still uncertain. Herein, we have attempted to dissect some of the chemical characteristics of amine-thiol cosolvents, with a special interest taken towards a mixture of ethylenediamine (en) and mercaptoethanol (ME). Conductivity was measured for multiple amine-thiol combinations at different ratios to determine extent of ionization in solution, with en-ME having one of the highest solution conductivities. Exposing the solution to air for several days was found to decrease the conductivity of en-ME, indicating the formation of …
Uio-Type Metal-Organic Framework Derivatives As Sorbents For The Detection Of Gas-Phase Explosives, Matthew Ryan Sherrill
Uio-Type Metal-Organic Framework Derivatives As Sorbents For The Detection Of Gas-Phase Explosives, Matthew Ryan Sherrill
Legacy Theses & Dissertations (2009 - 2024)
The detection of energetic compounds – better known to the public as explosives – has is an important cornerstone of counterterrorism and homeland security . While significant advances have been achieved for the detection of trace explosives in various matrices such as soil, wastewater, and clothing, the detection of explosives in the gas phase remains challenging due to their infamously low vapor pressures. In this thesis, we leverage the high sensitivity of direct analysis in real-time mass spectrometry (DART-MS) and the microporosity of metal-organic frameworks (MOFs) to adsorb and therefore concentrate explosives from the vapor phase and subsequently detect them …
Reliability Characterization Of A Low-K Dielectric Using Its Magnetoresistance As A Diagnostic Tool, Philip Alister Williams
Reliability Characterization Of A Low-K Dielectric Using Its Magnetoresistance As A Diagnostic Tool, Philip Alister Williams
Legacy Theses & Dissertations (2009 - 2024)
The introduction of low dielectric constant materials within the integrated circuit (IC) chip technology industry was a concerted effort to decrease the resistance-capacitance (RC) time delay inherent within the dielectric materials used as insulators. This stems from a demand for greater device density per IC chip and decreased feature sizes but is fast becoming a reliability issue. Concomitant with the demand for decreased feature sizes, also in adherence with Moore’s Law (which states that the number of devices on a die doubles every two years), is a reduction in device speed and performance due to device intra-level interconnection signal delays. …
Device Engineering Of Algan/Gan Hemts For Applications In Power-Electronic And Sensing, Isra Mahaboob
Device Engineering Of Algan/Gan Hemts For Applications In Power-Electronic And Sensing, Isra Mahaboob
Legacy Theses & Dissertations (2009 - 2024)
The research work presented in this Ph.D. thesis focuses on the engineering of AlGaN/GaN high electron mobility transistors (HEMTs) for the development of future device technology in power electronic and sensing applications.
Synthesis And Adsorption Experiments With Metal-Organic Frameworks For High School And Undergraduate Laboratory Settings, Kate Holley
Legacy Theses & Dissertations (2009 - 2024)
Seven experiments are described and outlined here that introduce high school and undergraduate students to metal–organic frameworks (MOFs) and their applications. The experiments were designed to be completed with basic laboratory equipment and supplies and without the use of expensive characterization instruments, simulating typical high school chemistry laboratory conditions. Students synthesized two well-known MOFs, HKUST-1 and aluminum fumarate, using simple, safe, and rapid methods (fast enough to be performed within the time constrains of a typical high school class). Students then use their synthesized MOFs to explore their inherent sorption properties. In one set of experiments, the synthesized MOFs are …
Investigation Of Optical Second Harmonic Generation From Si (100) With Process Tailored Surface & Embedded Ag Nanostructures For Advanced Si Nonlinear Nanophotonics, Gourav Bhowmik
Legacy Theses & Dissertations (2009 - 2024)
The challenge of current microelectronic architecture in transmission bandwidth and power consumption can be potentially solved by using silicon photonics technologies that are compatible with modern CMOS fabrication. One of the critical active photonic devices for Si photonics is a Si based optical modulator. Most of the reported silicon modulators rely on the free carrier plasma dispersion effect. In those cases, a weak change of the refractive index obtained by carrier accumulation, injection or depletion is utilized in a Mach-Zehnder interferometer or a microring resonator to achieve intensity modulation, rendering them difficult for chip-level implementation due to a large footprint …
Low Energy Electron Interactions With Aliphatic And Aromatic Self-Assembled Monolayers On Au(111), Jodi Marie Grzeskowiak
Low Energy Electron Interactions With Aliphatic And Aromatic Self-Assembled Monolayers On Au(111), Jodi Marie Grzeskowiak
Legacy Theses & Dissertations (2009 - 2024)
Understanding the interaction of low energy electrons with organic thin films is important for the development of many technological applications, one of which is extreme ultra-violet (EUV, 92 eV) lithography. At this energy, the photon will produce an electron cascade that induces most of the chemical changes within the photoresist. In order to better understand these interactions, electron scattering experiments have been performed on self-assembled monolayers (SAMs) of the aliphatic molecule 1-decanethiol and the aromatic molecule 1,1’-biphenyl-4-thiol grown on Au(111) via vapor phase deposition. The molecules take on either a lying down (LD) or standing up (SU) geometry depending on …
Synthesis Of Cadmium Arsenide Semiconductor Nanoparticles, Superatomic Silver Clusters, And Silver Coordination Polymers, Sarthak Jashubhai Patel
Synthesis Of Cadmium Arsenide Semiconductor Nanoparticles, Superatomic Silver Clusters, And Silver Coordination Polymers, Sarthak Jashubhai Patel
Legacy Theses & Dissertations (2009 - 2024)
Nanomaterials have chemical, electronic, optical, and other properties distinct from their bulk counterparts. However, the atom-precise synthesis of these materials remains a challenge, leaving open many scientific questions regarding the size regime between nanoparticulate (quantum confined) and bulk character. In this work, efforts toward the synthesis of nanoparticulate and atom-precise metal and semimetal materials are described. The synthesis of II-V semiconductor Cd3As2 having a near-zero bandgap is discussed. Analysis by UV-Vis absorption spectroscopy and powder X-ray diffraction indicate the formation of material with unexpected crystallinity and absorption properties The interaction between the molecular source of As and the solvent was …
Cvd Molybdenum Disulfide : Material And Device Engineering, Eui Sang Song
Cvd Molybdenum Disulfide : Material And Device Engineering, Eui Sang Song
Legacy Theses & Dissertations (2009 - 2024)
Molybdenum disulfide (MoS2) is a semiconducting 2D layered material that has attracted a lot of attention due to its material properties for electronics and optoelectronics device applications. These include a layer-dependent band gap, an indirect to direct energy transition at monolayer state, and strong light-matter interaction. A large majority of 2D materials and devices have been studied through micromechanical exfoliation for extraction and electron beam lithography for device fabrication. These methodologies while able to generate high quality materials and precisely fabricated devices, are not suitable for large scale production. Efforts have been made to make MoS2 and other 2D materials …
Dna Functionalized Nanoparticles In Nanobiosensor And Sensor Array Development For Molecular Diagnostics And In Vitro Identification Of Biomolecules, Mustafa Salih Hizir
Dna Functionalized Nanoparticles In Nanobiosensor And Sensor Array Development For Molecular Diagnostics And In Vitro Identification Of Biomolecules, Mustafa Salih Hizir
Legacy Theses & Dissertations (2009 - 2024)
Nucleic acid technology along with vast variety of nanomaterials has demonstrated a great potential in many applications from biosensing studies to molecular diagnostics, from biomedical and bioanalytical research to environmental analysis. Especially short single stranded (ss) DNA molecules, called oligonucleotides, are extraordinary biopolymers featuring diverse functionality on the nanoparticles thanks to their high degree of programmability, target-specific binding or cleavage, molecular recognition ability, structure-switching capability, and unique interactions at the bio-nano interfaces. Among those, there have been many biosensing applications utilizing ss DNAs and numerous nanomaterials through various detection techniques such as fluorometric, colorimetric or electrochemical methods. Although many groundbreaking …
Genetically Engineered Polypeptides As Biomimetic Light Harvesting Optical Antenna, Jason P. Seeley
Genetically Engineered Polypeptides As Biomimetic Light Harvesting Optical Antenna, Jason P. Seeley
Legacy Theses & Dissertations (2009 - 2024)
Natural resources useful for the generation of energy are limited. The development of efficient materials capable of utilizing the abundant free solar radiation is of considerable interest. Utilization of otherwise wasted energy sources, including solar radiation, is a progressive step in the quest for sustainable energy. Solar radiation incident upon the earth’s surface exceeds current energy requirements and motivates scientists to investigate and develop functional devices and nanomaterials including light harvesting complexes (LHC) capable of capturing solar radiation for energy conversion and storage.
Technology Development For Detection Of Circulating Disease Biomarkers From Liquid Biopsies Using Multifunctional Nanomaterials, Mustafa Balcioglu
Technology Development For Detection Of Circulating Disease Biomarkers From Liquid Biopsies Using Multifunctional Nanomaterials, Mustafa Balcioglu
Legacy Theses & Dissertations (2009 - 2024)
Despite the advance health care, devastating health conditions such as cancer and infectious diseases that affect populations worldwide are too often not diagnosed until morbid symptoms become apparent in the late phase. Obtaining an early and accurate diagnosis that reveal a hidden lethal threat before the disease becomes complicated may dramatically reduce the severity of its impact on the patient’s life and increase the probability of survival. For example, in the case of ovarian cancer, which is the fifth most common malignancy and the fifth leading cause of cancer mortality in women in the US, the 5-year relative survival is …
Homo- And Heterometallic Bis(Pentafluorobenzoyl)Methanide Complexes Of Copper(Ii) And Cobalt(Ii), Janell Crowder
Homo- And Heterometallic Bis(Pentafluorobenzoyl)Methanide Complexes Of Copper(Ii) And Cobalt(Ii), Janell Crowder
Legacy Theses & Dissertations (2009 - 2024)
β-Diketones are well known to form metal complexes with practically every known metal and metalloid. Metal complexes of fluorinated β-diketones generally exhibit increased volatility and thermal stability compared to the non-fluorinated analogues, and thus are used extensively in various chemical vapor deposition (CVD) processes for the deposition of metal, simple or mixed metal oxides, and fluorine-doped metal oxide thin films. Furthermore, the electron-withdrawing nature of the fluorinated ligand enhances the Lewis acidity of a coordinatively unsaturated metal center which facilitates additional coordination reactions. The physical and structural properties of fluorinated β-diketonate complexes are discussed in Chapter 1 …
Computational Optimization And Characterization Of Molecularly Imprinted Polymers, Jacob Jordan Terracina
Computational Optimization And Characterization Of Molecularly Imprinted Polymers, Jacob Jordan Terracina
Legacy Theses & Dissertations (2009 - 2024)
Molecularly imprinted polymers (MIPs) are a class of materials containing sites capable of selectively binding to the imprinted target molecule. Computational chemistry techniques were used to study the effect of different fabrication parameters (the monomer-to-target ratios, pre-polymerization solvent, temperature, and pH) on the formation of the MIP binding sites. Imprinted binding sites were built in silico for the purposes of better characterizing the receptor – ligand interactions. Chiefly, the sites were characterized with respect to their selectivities and the heterogeneity between sites.
Elucidation And Optimization Of Resistive Random Access Memory Switching Behavior For Advanced Computing Applications, Zahiruddin Alamgir
Elucidation And Optimization Of Resistive Random Access Memory Switching Behavior For Advanced Computing Applications, Zahiruddin Alamgir
Legacy Theses & Dissertations (2009 - 2024)
RRAM has recently emerged as a strong candidate for non-volatile memory (NVM). Beyond memory applications, RRAM holds promise for use in performing logic functions, mimicking neuromorphic activities, enabling multi-level switching, and as one of the key elements of hardware based encryption or signal processing systems. It has been shown previously that RRAM resistance levels can be changed by adjusting compliance current or voltage level. This characteristic makes RRAM suitable for use in setting the synaptic weight in neuromorphic computing circuits. RRAM is also considered as a key element in hardware encryption systems, to produce unique and reproducible signals. However, a …
Modeling And Studying The Effect Of Texture And Elastic Anisotropy Of Copper Microstructure In Nanoscale Interconnects On Reliability In Integrated Circuits, Adarsh Basavalingappa
Modeling And Studying The Effect Of Texture And Elastic Anisotropy Of Copper Microstructure In Nanoscale Interconnects On Reliability In Integrated Circuits, Adarsh Basavalingappa
Legacy Theses & Dissertations (2009 - 2024)
Copper interconnects are typically polycrystalline and follow a lognormal grain size distribution. Polycrystalline copper interconnect microstructures with a lognormal grain size distribution were obtained with a Voronoi tessellation approach. The interconnect structures thus obtained were used to study grain growth mechanisms, grain boundary scattering, scattering dependent resistance of interconnects, stress evolution, vacancy migration, reliability life times, impact of orientation dependent anisotropy on various mechanisms, etc. In this work, the microstructures were used to study the impact of microstructure and elastic anisotropy of copper on thermal and electromigration induced failure.
Materials For Giant Spin Hall Effect Devices, Avyaya Jayanthinarasimham
Materials For Giant Spin Hall Effect Devices, Avyaya Jayanthinarasimham
Legacy Theses & Dissertations (2009 - 2024)
Studies presented in this thesis are an effort to control the growth of β W and explore
Exploring Magnetic Nanostructures Embedded Within Single-Crystal Silicon For Generation Of Spin-Polarized Carriers, Machara Krishna Girish Malladi
Exploring Magnetic Nanostructures Embedded Within Single-Crystal Silicon For Generation Of Spin-Polarized Carriers, Machara Krishna Girish Malladi
Legacy Theses & Dissertations (2009 - 2024)
Integrating magnetic functionalities with silicon holds the promise of developing, in the most dominant semiconductor, a paradigm-shift information technology based on the manipulation and control of electron spin and charge. Here, we demonstrate an ion implantation approach enabling the synthesis of a ferromagnetic layer within a defect free Si environment by exploiting an additional implant of hydrogen in a region deep below the metal implanted layer. Upon post-implantation annealing, nanocavities created within the H-implanted region act as trapping sites for gettering the implanted metal species, resulting in the formation of metal nanoparticles in a Si region of excellent crystal quality. …
Development Of Multilayer Titanium Nitride-Based Coatings As Corrosion Resistant Films For Stainless Steel Bipolar Plates In Pem Fuel Cells, Nicholas Padula
Development Of Multilayer Titanium Nitride-Based Coatings As Corrosion Resistant Films For Stainless Steel Bipolar Plates In Pem Fuel Cells, Nicholas Padula
Legacy Theses & Dissertations (2009 - 2024)
High cost and short lifetime are the two main reasons why the PEM fuel cell has not reached a widespread, disruptive level of commercialization. Conventional graphite bipolar plates are responsible for about 45% of the cost and 85% of the total weight of a single cell. These measures are linked to difficult machining of thick, brittle graphite and processing needed to render graphite non-porous. Stainless steel is suggested as the replacement bipolar plate material due to its favorable mechanical properties, ease of manufacturing and relatively low price, but requires a cost-effective coating as a non-conductive oxide forms on the bare …
Effect Of Ion Flux (Dose Rate) In Source-Drain Extension Ion Implantation For 10-Nm Node Finfet And Beyond On 300/450mm Platforms, Ming-Yi Shen
Legacy Theses & Dissertations (2009 - 2024)
The improvement of wafer equipment productivity has been a continuous effort of the semiconductor industry. Higher productivity implies lower product price, which economically drives more demand from the market. This is desired by the semiconductor manufacturing industry. By raising the ion beam current of the ion implanter for 300/450mm platforms, it is possible to increase the throughput of the ion implanter. The resulting dose rate can be comparable to the performance of conventional ion implanters or higher, depending on beam current and beam size. Thus, effects caused by higher dose rate must be investigated further. One of the major applications …
Degradation And Exciton Energy Transfer Studies In Single-Walled Carbon Nanotube Bundles, Abhishek Gottipati
Degradation And Exciton Energy Transfer Studies In Single-Walled Carbon Nanotube Bundles, Abhishek Gottipati
Legacy Theses & Dissertations (2009 - 2024)
Single walled carbon nanotubes (SWNTs) due to their unique optical behavior, large surface area, robust mechanical strength and electrical properties make them one of the ideal candidates for sensing and opto-electronic applications. In this work, we explore the energy transfer (exciton energy transfer-EET) phenomena occurring between nanotubes in bundles, using resonance Raman spectroscopy.
Development Of Iii-Sb Based Technologies For P-Channel Mosfet In Cmos Applications, Shailesh Kumar Madisetti
Development Of Iii-Sb Based Technologies For P-Channel Mosfet In Cmos Applications, Shailesh Kumar Madisetti
Legacy Theses & Dissertations (2009 - 2024)
The continuous scaling of silicon CMOS predicts the end of roadmap due to the difficulties such as that arise from electrostatic integrity, design complexities, and power dissipation. These fundamental and practical limitations bring the need for innovative design architectures or alternate materials with higher carrier transport than current Si based materials. New device designs such as multigate/gate-all-around architectures improve electrostatics while alternate materials like III-Vs such as III-As for electrons and III-Sbs for holes increase operational speed, lower power dissipation and thereby improve performance of the transistors due to their low effective mass and faster transport properties. Further, application of …
Magnetoresistance Of A Low-K Dielectric, Brian Thomas Mcgowan
Magnetoresistance Of A Low-K Dielectric, Brian Thomas Mcgowan
Legacy Theses & Dissertations (2009 - 2024)
Low-k dielectrics have been incorporated into advanced computer chip technologies as a part of the continuous effort to improve computer chip performance. One drawback associated with the implementation of low-k dielectrics is the large leakage current which conducts through the material, relative to silica. Another drawback is that the breakdown voltage of low-k dielectrics is low, relative to silica [1]. This low breakdown voltage makes accurate reliability assessment of the failure mode time dependent dielectric breakdown (TDDB) in low-k dielectrics critical for the successful implementation of these materials. The accuracy with which one can assess this reliability is currently a …
Investigation Of Contact Properties At Metal Graphene Junctions, Their Degradation And Intrinsic Limitations, Zhenjun Zhang
Investigation Of Contact Properties At Metal Graphene Junctions, Their Degradation And Intrinsic Limitations, Zhenjun Zhang
Legacy Theses & Dissertations (2009 - 2024)
Graphene is a two-dimensional material, comprised of a monolayer of carbon in a hexagonal lattice. Since 2004, the most promising applications of this material are high frequency devices (such as mixers and power amplifiers), as well as flexible and transparent electronics. However, these applications can’t be realized without a proper contact metal. With more understanding of the contact properties, the range of prospects for graphene’s applications can be better defined.
Tailoring The Optical Properties Of Silicon With Ion Beam Created Nanostructures For Advanced Photonics Applications, Perveen Akhter
Tailoring The Optical Properties Of Silicon With Ion Beam Created Nanostructures For Advanced Photonics Applications, Perveen Akhter
Legacy Theses & Dissertations (2009 - 2024)
In today’s fast life, energy consumption has increased more than ever and with that the demand for a renewable and cleaner energy source as a substitute for the fossil fuels has also increased. Solar radiations are the ultimate source of energy but harvesting this energy in a cost effective way is a challenging task. Si is the dominating material for microelectronics and photovoltaics. But owing to its indirect band gap, Si is an inefficient light absorber, thus requiring a thickness of solar cells beyond tens of microns which increases the cost of solar energy. Therefore, techniques to increase light absorption …
Investigating The Size Dependent Material Properties Of Nanoceria, Bushra B. Alam
Investigating The Size Dependent Material Properties Of Nanoceria, Bushra B. Alam
Legacy Theses & Dissertations (2009 - 2024)
Nanoceria is widely being investigated for applications as support materials for fuel cell catalysts, free radical scavengers, and as chemical and mechanical abrasives due to its high antioxidant capacity and its oxygen buffering capacity. This antioxidant or oxygen buffering capacity has been reported to be highly size dependent and related to its redox properties. However, the quantification of this antioxidant capacity has not been well defined or understood and has been often been carried out using colorimetric assays which do not directly correlate to ceria nanoparticle properties. Fabrication rules for developing materials with optimal antioxidant/oxygen buffering capacities are not yet …
Development Of Enhanced Window Layers For Cigs Photovoltaic Devices, James Nicholas Alexander
Development Of Enhanced Window Layers For Cigs Photovoltaic Devices, James Nicholas Alexander
Legacy Theses & Dissertations (2009 - 2024)
Photovoltaic devices are among the promising options for sustainable future energy generation. Thin film solar cells have demonstrated the ability to be a low-cost solution to clean renewable energy and are cost competitive with current silicon based photovoltaic devices. One of the most promising thin film devices right now is the Copper Indium Gallium Selenide (CIGS) solar cell with maximum reported power conversion efficiency of 22.3%. The Transparent Conducting Oxide (TCO) which is the top layer of the CIGS device also known as the window layer, is responsible for collecting the electrons generated in the CIGS device and conducting them …
Experimental And Theoretical Investigations Of Cadmium Diffusion In Vacancy-Rich Cu(In, Ga)Se₂ Material, Norb Biderman
Experimental And Theoretical Investigations Of Cadmium Diffusion In Vacancy-Rich Cu(In, Ga)Se₂ Material, Norb Biderman
Legacy Theses & Dissertations (2009 - 2024)
Copper indium gallium selenide (Cu(In,Ga)Se2 or CIGS) has become a significant topic of research and development for photovoltaic application. CIGS photovoltaic devices have demonstrated record conversion efficiencies however are still below the maximum solar conversion efficiency. Losses in performance have been attributed structural defects including vacancies, doping, grain boundaries, and compositional non-uniformity that are poorly understood and controlled.
Texture And Microstructure Of Ipvd Copper Manganese Seed In 1 Μm & 70 Nm Wide Damascene Trenches, Robert Stuart Brown
Texture And Microstructure Of Ipvd Copper Manganese Seed In 1 Μm & 70 Nm Wide Damascene Trenches, Robert Stuart Brown
Legacy Theses & Dissertations (2009 - 2024)
This thesis describes the grain texture and microstructure of Ionized Physical Vapor Deposition (iPVD) Copper Manganese seed in 1 µm and 70 nm wide damascene trenches. Using Transmission Electron Microscopy (TEM) imaging and diffraction pattern analysis, the grain size and general orientation of the grains were determined. It was found that the 1 µm wide trenches contained larger grains and more texture than that of the 70 nm wide trenches. While this thesis builds upon previous work by Brendan O’Brien in the Dunn group, one significantly different finding will be presented regarding the structure on the sidewall of the trenches. …
Initiated Chemical Vapor Deposition (Icvd) Polymer Thin Films : Structure-Property Effects On Thermal Degradation And Adhesion, Vijay Jain Bharamaiah Jeevendrakumar
Initiated Chemical Vapor Deposition (Icvd) Polymer Thin Films : Structure-Property Effects On Thermal Degradation And Adhesion, Vijay Jain Bharamaiah Jeevendrakumar
Legacy Theses & Dissertations (2009 - 2024)
Opportunities and challenges for chemical vapor deposition (CVD) of polymer thin films stems from their applications in electronics, sensors, and adhesives with demands for control over film composition, conformity and stability. Initiated chemical vapor deposition (iCVD) is a subset of the CVD technique that conjoins bulk free-radical polymerization chemistry with gas-phase processing. The novelty of iCVD technique stems from the use of an initiator that can be activated at low energies (150 – 300 °C) to react with surface adsorbed monomer to form a polymer film. This reduces risk for potential unwarranted side-reactions.