Nanotechnology Fabrication Commons^™

Grand Challenges In Low Temperature Plasmas, Xinpei Lu, Peter J. Bruggeman, Stephan Reuter, George Naidis, Annemie Bogaerts, Mounir Laroussi, Michael Keidar, Eric Robert, Jean-Michel Pouvesle, Dawei Liu, Kostya (Ken) Ostrikov

Electrical & Computer Engineering Faculty Publications

Low temperature plasmas (LTPs) enable to create a highly reactive environment at near ambient temperatures due to the energetic electrons with typical kinetic energies in the range of 1 to 10 eV (1 eV = 11600K), which are being used in applications ranging from plasma etching of electronic chips and additive manufacturing to plasma-assisted combustion. LTPs are at the core of many advanced technologies. Without LTPs, many of the conveniences of modern society would simply not exist. New applications of LTPs are continuously being proposed. Researchers are facing many grand challenges before these new applications can be translated to practice. …

Iii-Nitride Nanostructures: Photonics And Memory Device Applications, Barsha Jain

Dissertations

III-nitride materials are extensively studied for various applications. Particularly, III-nitride-based light-emitting diodes (LEDs) have become the major component of the current solid-state lighting (SSL) technology. Current III-nitride-based phosphor-free white color LEDs (White LEDs) require an electron blocking layer (EBL) between the device active region and p-GaN to control the electron overflow from the active region, which has been identified as one of the primary reasons to adversely affect the hole injection process. In this dissertation, the effect of electronically coupled quantum well (QW) is investigated to reduce electron overflow in the InGaN/GaN dot-in-a-wire phosphor-free white LEDs and to improve the …

Synthetic Aperture Optical Imaging Interferometric Microscopy With Improved Image Quality, Preyom K. Dey

Electrical and Computer Engineering ETDs

The resolution limit of optical microscopy can be extended by using Imaging Interferometric Microscopy (IIM), which uses a low numerical aperture (NA) objective lens to achieve resolution equivalent to that of a high-NA objective lens with multiple sub-images. Along with the resolution enhancement challenge, IIM often suffers from poor image quality. In this dissertation, several image quality improvement methods are proposed and verified with simulation and experimental results. Next, techniques to extend the resolution limit of IIM to ≤ 100nm using a low-NA objective lens are demonstrated. An experimental technique of using a grating coupler on …

Machine Learning Approach To Stability Analysis Of Semiconductor Memory Element, Ravindra Thanniru, Gautam Kapila, Nibhrat Lohia

SMU Data Science Review

Memory stability analysis traditionally relied heavily on circuit simulation-based approaches that run Monte Carlo (MC) analysis over various manufacturing and use condition parameters. This paper researches application of Machine Learning approaches for memory element failure analysis which could mimic simulation-like accuracy and minimize the need for engineers to rely heavily on simulators for their validations. Both regressor and classifier algorithms are benchmarked for accuracy and recall scores. A high recall score implies fewer escapes of fails to field and is the metric of choice for comparing algorithm. The paper identifies that recall score in excess of 0.97 can be achieved …

Thermometry Via Diffusion In Ferrous Core-Shell Nanoparticles For Induction Heating Applications, Hayden Carlton

Graduate Theses and Dissertations

Induction heating causes the release of enormous amounts of heat from dispersed magnetic nanoparticles. While the rate of heat transfer can be easily quantified calorimetrically, measuring the temperature of the nanoparticles on the nanoscale presents experimental challenges. Fully characterizing the temperature and thermal output of these magnetic particles is necessary to gauge overall heating efficiency and to provide a more holistic understanding of heat transfer on the nanoscale. Herein, this dissertation seeks to develop a novel nanoparticle thermometry technique, which correlates diffusion behavior in core-shell nanoparticles to local temperature. Initial measurements suggested that heating silica capped ferrous nanoparticles (SCNPs) via …

Multifunctional Programmable Self-Assembled Nanoparticles In Nanomedicine, Yoshie Sakamaki

Graduate Theses and Dissertations

Developing methodologies to control the architecture of nanoparticles (NPs) at the atomic level prevents their inhomogeneity and leads to a variety of expected functions. Rationally designed nanoparticles can either be programmed or crystallized structures into pre-determined structures achieving tunable particle pore size and physiochemistry. In this dissertation, two broad classes of multifunctional nanoparticles are developed, metal-organic frameworks and DNA-NP aggregates.

Metal-organic frameworks are a novel class of highly porous crystalline materials built from organic linkers and metal cluster-based secondary building units. However, applications in bioremediation have not been developed very well especially in applications regarding drug delivery systems (DDS). The …

Incorporation Of Zinc In Pre-Alloyed Cuin[Zn]S2/Zns Quantum Dots, Jean Carlos Morales Orocu

Graduate Theses and Dissertations

Since the early 2000s heavy-metal-free quantum dots (QDs) such as CuInS2/ZnS have attempted to replace CdSe, their heavy-metal-containing counterparts. CuInS2/ZnS is synthesized in a two-step process that involves the fabrication of CuInS2 (CIS) nanocrystals (NCs) followed by the addition of zinc precursors. Instead of the usual core/shell architecture often exhibited by binary QDs, coating CIS QDs results in alloyed and/or partially alloyed cation-exchange (CATEX) QDs. The effect that zinc has on the properties of CIS NCs was studied by incorporating zinc during the first step of the synthesis. Different In:Cu:Zn ratios were employed in this study, maintaining a constant 4:1 …

Fabricating Nanophotonic Devices Using Nanofabrication Techniques, Scott Cummings

Student Scholar Symposium Abstracts and Posters

Nanofabrication processes are widely used to make the integrated circuits and computer chips that are ubiquitous in today’s technology. These fabrication processes can also be applied to the creation of nanophotonic devices. The ways in which we apply these fabrication techniques in the field of photonics is often constrained by the technologies used for electronics manufacturing which presents an interesting engineering challenge. These limitations include availability and cost of certain fabrication equipment and techniques required to create state-of-the-art nanophotonic devices. Through work with the University of California Irvine nano-fabrication cleanroom, we designed and fabricated various integrated photonic components including grating …

Study Of Thick Indium Gallium Nitride Graded Structures For Future Solar Cell Applications, Manal Abdullah Aldawsari

Graduate Theses and Dissertations

Indium gallium nitride (InxGa1-xN) materials have held great potential for the optoelectronic industry due to their electrical and optical properties. The tunable band gap that can span the solar spectrum was one of the most significant features that attracted researchers’ attention. The band gap can be varied continuously from 0.77 eV for InN to 3.42 eV for GaN, covering the solar spectrum from near infrared to near ultraviolet. Additionally, it has a high absorption coefficient on the order of ∼105 cm−1, a direct band gap, high radiation resistance, thermal stability, and so on. Nevertheless, the epitaxial growth of high quality …

Additive Manufacturing Using Robotic Manipulators, Fdm, And Aerosol Jet Printers., Alexander Curry

Electronic Theses and Dissertations

Additive manufacturing has created countless new opportunities for fabrication of devices in the past few years. Advances in additive manufacturing continue to change the way that many devices are fabricated by simplifying processes and often lowering cost. Fused deposition modeling (FDM) is the most common form of 3D printing. It is a well-developed process that can print various plastic materials into three-dimensional structures. This technology is used in a lot of industries for rapid prototyping and sometimes small batch manufacturing. It is very inexpensive, and a prototype can be created in a few hours, rather than days. This is useful …

Modeling And Characterization Of Optical Metasurfaces, Mahsa Torfeh

Masters Theses

Metasurfaces are arrays of subwavelength meta-atoms that shape waves in a compact and planar form factor. During recent years, metasurfaces have gained a lot of attention due to their compact form factor, easy integration with other devices, multi functionality and straightforward fabrication using conventional CMOS techniques. To provide and evaluate an efficient metasurface, an optimized design, high resolution fabrication and accurate measurement is required. Analysis and design of metasurfaces require accurate methods for modeling their interactions with waves. Conventional modeling techniques assume that metasurfaces are locally periodic structures excited by plane waves, restricting their applicability to gradually varying metasurfaces that …

Towards Higher Power Factor In Semiconductor Thermoelectrics: Bandstructure Engineering And Potential Barriers, Adithya Kommini

Doctoral Dissertations

To keep up with the current energy demand and to sustain the growth requires efficient use of existing resources. One of the ways to improve efficiency is by converting waste heat to electricity using thermoelectrics. Thermoelectric devices work on the principle of Seebeck effect, where an applied temperature difference across the material results in a potential difference in the material. The possibility of drastic improvements in the efficiency of thermoelectric (TE) devices using semiconductor nanostructured materials renewed interest in thermoelectrics over the last three decades. Introducing confinement, interfaces, and quantum effects using nanostructures for additional control of charge and phonon …

Tailoring Plasmon Excitations In Alpha − T 3 Armchair Nanoribbons, Andrii Iurov, Liubov Zhemchuzhna, Godfrey Gumbs, Danhong Huang, Paula Fekete, Farhana Anwar, Dipendra Dahal, Nicholas Weekes

Publications and Research

We have calculated and investigated the electronic states, dynamical polarization function and the plasmon excitations for α − T ₃ nanoribbons with armchair-edge termination. The obtained plasmon dispersions are found to depend significantly on the number of atomic rows across the ribbon and the energy gap which is also determined by the nanoribbon geometry. The bandgap appears to have the strongest effect on both the plasmon dispersions and their Landau damping. We have determined the conditions when relative hopping parameter α of an α − T ₃ lattice has a strong effect on the plasmons which makes our material distinguished …

Metasurface Design And Optimization With Adjoint Method, Mahdad Mansouree

Doctoral Dissertations

The invention and advancement of optical devices have tremendously changed our life. Devices such as cameras, displays and optical sensors are now an integral part of our lives. Moreover, with the rapid growth in new markets such as virtual reality (VR), augmented reality (AR), autonomous vehicles and internet of things (IoT) the need for optical devices is expected to grow considerably. Recent advances in nano-fabrication techniques have spurred a new wave of interest in optical metasurfaces. Metasurfaces are arrays of wisely selected nano-scattereres that generate desired transformation on the incident light. Metasurfaces provide a new platform for the development of …

Development Of A Point-Of-Use Testing Platform For Detecting Bacteria Infection In Raw Milk, Xin Xia

Masters Theses

The detection and quantification of bacteria are essential to environment and food quality monitoring. Escherichia coli (E. coli) is a common pathogen, also a causative agent of mastitis. Traditional methods usually require samples to be tested in a laboratory. However, sending samples to remote lab increases the cost of time and money spent on delivery. Sometimes, samples can degrade during this long progress and cause inaccuracy. A low cost and reusable sensor is designed to perform on-site quantification. The sensor composed of two layers of asymmetrical mesh electrodes, which is used in coordination magnetic microparticles functionalized with bacterium-specific antibody. Immunological …

Investigation Of Membrane Based Processes For Biomedical Applications, Efecan Pakkaner

Graduate Theses and Dissertations

As substantial developments were achieved in nanotechnology and polymer engineering, especially in the last few decades, the use of membranes and membrane-based procedures was found to be expanding into more and more research and development areas; including biological engineering, life sciences and biomedical engineering. Not only have they been the main focus of meaningful research, but they have also been the main pieces of the solutions to very thorny problems encountered within a wide range of applications from microfluidics to water treatment, thanks to their versatility, cost-effectiveness and biocompatibility, when compared to conventional separation techniques. To celebrate and embrace these …

The Effects Of The Transient And Performance Loss Rates On Pv Output Performance, Chibuisi Chinasaokwu Okorieimoh, Brian Norton, Michael Conlon

Conference papers

Solar photovoltaic (PV) panels experience long-term performance degradation as compared to their initial performance, resulting in lower like-per-like efficiencies and performance ratios. Manufacturers of solar photovoltaic modules normally guarantee a lifespan of more than 20 years. To meet such commitments, it is important to monitor and mitigate PV module degradation during this period, as well as beyond, to recognize maintenance and repair needs. Solar PV modules degrade over time, becoming less effective, less reliable, and eventually unusable. The effects of transient and performance loss rates on the output performance of polycrystalline silicon (p-Si) solar PV modules are the focus of …

Design And Characterization Of Standard Cell Library Using Finfets, Phanindra Datta Sadhu

Master's Theses

The processors and digital circuits designed today contain billions of transistors on a small piece of silicon. As devices are becoming smaller, slimmer, faster, and more efficient, the transistors also have to keep up with the demands and needs of the daily user. Unfortunately, the CMOS technology has reached its limit and cannot be used to scale down due to the transistor's breakdown caused by short channel effects. An alternative solution to this is the FinFET transistor technology, where the gate of the transistor is a three dimensional fin that surrounds the transistor and prevents the breakdown caused by scaling …

Low-Energy Memristors & High-Nonlinearity Selector For Dense Passive Cross-Bar Arrays, Navnidhi K. Upadhyay

Doctoral Dissertations

Memristor or RRAM (Resistive Random Access Memory) based crossbar array architecture (CBA) is considered a leading contender for the next-generation non-volatile memory (NVM) as well as for future computing paradigms, such as in-memory computing, neuromorphic computing, neural networks, analog computing, reconfigurable computing, etc. Among many other attractive properties, memristors’ simple and dense 3D stackable structure is an essential enabler of these promising applications. However, the simplicity and high density of CBA comes at a price. CBA suffers from the so-called sneak path currents flowing through the unselected cells, which severely affects the read margin, makes CBA more power-hungry, increases the …

Analysis Of Photodetector Based On Zinc Oxide And Cesium Lead Bromide Heterostructure With Interdigital Metallization, Tanveer Ahmed Siddique

Graduate Theses and Dissertations

In this thesis, photodetector based on the zinc oxide and cesium lead bromide hetero structure were fabricated and characterized. Zinc oxide (ZnO) nanoparticles were synthesized using solution processing and cesium lead bromide (CsPbBr3) thin film was synthesized using two step deposition method. Three phonon modes were obtained by the Raman spectroscopy of ZnO nanoparticles. X-ray diffraction spectra of ZnO exhibits five exciton peaks which denotes that the synthesized ZnO structure was of good crystallinity with wurtzite hexagonal phase. The absorbance spectrum of ZnO shows the bandgap (Eg) in the order of 3.5 eV that aligns with reported results. The photoluminescence …