Electronic Devices and Semiconductor Manufacturing Commons^™

Gamma And Neutron Irradiation Effect On Ga-Polar And N-Polar Gan Based Diodes, Farnood Mirkhosravi

Optical Science and Engineering ETDs

III-nitride material (GaN) shows a lot of potential for next-generation power electronics. This material is advantageous due to its wide bandgap, high electron mobility, high thermal and mechanical stability, small form factor, and higher radiation tolerance. The higher radiation tolerance makes the GaN-based devices more attractive for harsh-environment applications, like aerospace, nuclear reactor, and fusion facilities, particle accelerators, and post-detonation environments applications.

GaN due to its unique crystal structure can be grown in different orientations and can provide specific advantages in electronic and optoelectronic devices. While the Ga-polar orientation of GaN has been widely investigated for its proprieties, there are …

Group-Based Data Offloading Techniques Assisted By D2d Communication In 5g Mobile Network, Juma S Ally

Tanzania Journal of Engineering and Technology (TJET)

Machine type communication devices proposed as one of the substantial data collections in the 5G of wireless networks. However, the existing mobile communication network is not designed to handle massive access from the MTC devices instead of human type communication. In this context, we propose the device-to-device communication assisted a mobile terminal (smartphone) on data computing, focusing on data generated from a correlated source of machine type communication devices. We consider the scenario that the MTC devices after collecting the data will transmit to a smartphone for computing. With the limitation of computing resources at the smartphone, some data are …

An Experimental Approach Towards Pv-Based Solar System Sizing For An Engineering Laboratory, Muyideen O. Lawal

Tanzania Journal of Engineering and Technology (TJET)

This study aims at providing an experimental sizing procedure for a rooftop PV-based solar power system for an engineering laboratory. This was achieved by monitoring the peak power and energy delivered by an installed 20W solar panel into an 18 Ah battery. Knowledge of the average daily peak power and energy was used to determine the percentage rated capacity available for use and the sun hour. A load consumption comparison was also carried out with and without the connection of a load to inverter. In addition to this, the monitoring of the no-load consumption of the inverter was carried out. …

Efficient And Simple Heuristic Algorithm For Portfolio Optimization Collether John, Collether John

Tanzania Journal of Engineering and Technology (TJET)

Markowitz model considers what is termed as standard portfolio optimization. The portfolio optimization problem is a problem which based on asset allocation and diversification for maximum return with minimum risk. Thus, the standard portfolio optimization problem happens when the constraints considered are budget and no-short selling. In reality however, portfolio optimization has realistic constraints to be incorporated such as holding sizes, cardinality and transaction cost. When realistic constraints are added into portfolio optimization problem, it becomes too complex to be solved by standard optimization methods which in this case turns to be an extended portfolio optimization problem. Markowitz solution and …

Noncontact Liquid Crystalline Broadband Optoacoustic Sensors, Hengky Chandrahalim, Michael T. Dela Cruz

AFIT Patents

An optoacoustic sensor includes a liquid crystal (LC) cell formed between top and bottom plates of transparent material. A transverse grating formed across the LC cell that forms an optical transmission bandgap. A CL is aligned to form a spring-like, tunable Bragg grating that is naturally responsive to external agitations providing a spectral transition regime, or edge, in the optical transmission bandgap of the transverse grating that respond to broadband acoustic waves. The optoacoustic sensor includes a narrowband light source that is oriented to transmit light through the top plate, the LC cell, and the bottom plate. The optoacoustic sensor …

Machine Learning Applications To Static Timing Analysis, Waseem Mohamed Raslan

Theses and Dissertations

Modeling complex cell behavior is critical for accurate static timing analysis. Effective current source model, ECSM, and composite current source, CCS, waveform data compression became a necessity to reduce the size of technology files and increase the accuracy of the cell characterization data. We used deep learning nonlinear Autoencoders to compress voltage and current waveforms and compared them with singular value decomposition, SVD, approach. Autoencoders gave ~1.67x compression ratio for voltage waveforms better than SVD approach and gave 45x to 55x better compression ratio compared to other lossless techniques like bz2 and gzip. Autoencoders achieved ~1.7x compression ratio for complex …

Design And Analysis Of N-Path Filter For Radio Frequencies, Nathan M. Bergen

Master's Theses

Due to the growth of wireless communication many communication frequencies have grown increasingly dense. This density requires higher Q-factor to receive only the signal of interest. With the rise of smaller integrated circuits previous solutions used for filtering have become viable again. This paper explores whether the N-path filter is viable in the modern day for radio frequency receiver purposes. A non-differential N-path filter was created by utilizing Cadence Virtuoso with a working center frequency range of 750MHz to 1GHz while using TSMC technology. The desired quality factor of over 1,000 was reached while maintaining a total area of 800 …

Multifamily Complex Smart Locks For Property Management And Tenant Security, April Mills, Allen Chen, Dana Kumamoto, Michael Cook

Mechanical Engineering

Maintaining and managing hundreds of locks and physical keys for an apartment complex can be time consuming and costly, especially when the apartments turn over to new tenants. Our goal was to develop a smart door lock that is compatible with Obodo’s management app for apartment complexes to make accessing apartments secure and simpler for tenants and easier to manage for owners.

We designed and manufactured one smart door lock that is powered with four AA batteries and utilizes a dynamic NFC device and Bluetooth technology. The board can enter a sleep mode which reduces power consumption. The dynamic NFC …

Behavior, Switching Losses, And Efficiency Enhancement Potentials Of 1200 V Sic Power Devices For Hard-Switched Power Converters, Ali Mahmoud Salman Al-Bayati, Mohammad Abdul Matin

Electrical and Computer Engineering: Faculty Scholarship

Semiconductor power devices are the major constituents of any power conversion system. These systems are faced by many circumscriptions due to the operating constraints of silicon (Si) based semiconductors under certain conditions. The emergence and persistence evolution of wide bandgap technology pledge to transcend the restrictions imposed by Si based semiconductors. This paper presents a thorough experimental study and assessment of the performance of three power devices: 1200 V SiC cascode, 1200 V SiC MOSFET, and 1200 V Si IGBT under the same hardware setup. The study aims to capture the major attributes for each power device toward determining their …

Influence Of Materials And Design Parameters On Zinc Oxide Surface Acoustic Devices, Samuel B. Dewhitt

Theses and Dissertations

This thesis presents research into Zinc Oxide (ZnO) based resonators to include Width Extensional Mode (WEM), Length Extensional Mode (LEM), and Surface Acoustic Wave (SAW) devices. The design and operation of ZnO based SAW devices are investigated further to characterize design parameters and operating modes. Their design, fabrication, and results are discussed in detail. SAW device testing in conjunction with X-Ray Diffractometry (XRD) and Atomic Force Microscopy (AFM) are utilized to characterize ZnO and its deposition parameters on a variety of different substrates and interlayers, with different deposition temperatures and annealing parameters. These substrates include silicon, silicon oxide-on-silicon, and sapphire …

X-Band Rf Transmitter Design For Multi-Purpose Small Satellite Communication Operations, Omer F. Gumus

Master's Theses

This thesis provides a description of the analysis, design, and tests of an X-band RF Transmitter communication system for small satellites. X-band transmitter systems are becoming popular in the upcoming deep space missions. Most of the deep-space ground stations have been using X-band frequencies to receive or transmit signals. The X-band (<10 GHz) can offer lower atmospheric losses and up to a couple of Mbps data rates for multiple satellite operations. Nowadays, many small satellites have been using frequency bands such as VHF, UHF, L, and S-band frequencies for communication. From deep space to the ground station, the low-frequency ranges are inadequate in providing Mbps level data rates and enough bandwidth for deep space missions.

The main focus of this thesis was the development of the subsystems such as gain block amplifier, Mixer, Bandpass Filter, and RF power amplifier. The subsystems were designed separately, then they were connected together to perform an end-to-end system test. One of the thesis aims is to design …

Model-Based Design Of An Optimal Lqg Regulator For A Piezoelectric Actuated Smart Structure Using A High-Precision Laser Interferometry Measurement System, Grant P. Gallagher

Master's Theses

Smart structure control systems commonly use piezoceramic sensors or accelerometers as vibration measurement devices. These measurement devices often produce noisy and/or low-precision signals, which makes it difficult to measure small-amplitude vibrations. Laser interferometry devices pose as an alternative high-precision position measurement method, capable of nanometer-scale resolution. The aim of this research is to utilize a model-based design approach to develop and implement a real-time Linear Quadratic Gaussian (LQG) regulator for a piezoelectric actuated smart structure using a high-precision laser interferometry measurement system to suppress the excitation of vibratory modes.

The analytical model of the smart structure is derived using the …

Hinged Temperature-Immune Self-Referencing Fabry–Pérot Cavity Sensors, Jeremiah C. Williams, Hengky Chandrahalim

AFIT Patents

A passive microscopic Fabry-Pérot Interferometer (FPI) sensor includes a three-dimensional microscopic optical structure formed on a cleaved tip of the optical fighter using a two-photon polymerization process on a photosensitive polymer by a three-dimensional micromachining device. The three-dimensional microscopic optical structure having a hinged optical layer pivotally connected to a distal portion of a suspended structure. A reflective layer is deposited on a mirror surface of the hinged optical layer while in an open position. The hinged optical layer is subsequently positioned in the closed position to align the mirror surface to at least partially reflect a light signal back …

Design Of A Bandgap Voltage Reference, Nicolaus Vail

Electrical Engineering Undergraduate Honors Theses

This thesis details the design process of a bandgap voltage reference (BGR) integrated circuit in a 180 nm CMOS process. A BGR provides a constant DC voltage across a range of operating temperatures and supply voltages. By its nature, the circuit is intended as a reference, not to provide current, so the output would be connected to a very high impedance, such as the gate of a transistor. At 27°C, this design provides a 955 mV reference voltage given a nominal VDD of 3 V. From 20°C to 175°C, the output voltage has a variance of 7.2 mV (approximately 0.8%) …

Design & Analysis Of Mixed-Mode Integrated Circuit For Pulse-Shape Discrimination, Bryan Orabutt

McKelvey School of Engineering Graduate Student Theses & Dissertations

In nuclear science experiments it is usually necessary to determine the type of radiation, its energy and direction with considerable accuracy. The detection of neutrons and discriminating them from gamma rays is particularly difficult. A popular method of doing so is to measure characteristics intrinsic to the pulse shape of each radiation type in order to perform pulse-shape discrimination (PSD).

Historically, PSD capable systems have been designed with two approaches in mind: specialized analog circuitry, or digital signal processing (DSP). In this work we propose a PSD capable circuit topology using techniques from both the analog and DSP domains. We …

Automatic Testing Of Organic Strain Gauge Tactile Sensors., Brian P. Goulet

Electronic Theses and Dissertations

Human-Robot Interaction is a developing field of science, that is posed to augment everything we do in life. Skin sensors that can detect touch, temperature, distance, and other physical interaction parameters at the human-robot interface are very important to enhancing the collaboration between humans and machines. As such, these sensors must be efficiently tested and characterized to give accurate feedback from the sensor to the robot. The objective of this work is to create a diversified software testing suite that removes as much human intervention as possible. The tests and methodology discussed here provide multiple realistic scenarios that the sensors …

Design, Development, And Calibration Of An Electric Field Probe For Use On Sounding Rockets, Anthony Oreo

Doctoral Dissertations and Master's Theses

Earth’s ionosphere is a dynamic environment that has yet to be fully understood. Interactions of high-energy particles from space with atmospheric plasma and the Earth’s natural magnetic field create many interesting interactions, many of which have direct impacts on the planet and human life. Understanding the dynamics of the upper atmosphere is a compelling endeavor, with much of the research being conducted through high-altitude sounding rockets. These rockets allow for in-situ measurements of the physical parameters of the upper atmosphere which in turn helps in the answering of important questions in space science. In order to quantify the force a …

Ee Senior Design Project: Applications Of Wifi- Enabled Embedded Systems In Residential Security, Mariah Flint, Blake Kelly

Honors Capstone Projects and Theses

No abstract provided.

Second-Order Enhanced Coupling Strength Grating Out-Couplers For A Monolithic Laser-Electro-Absorption Modulator, Maryam Dezfuli

Electrical Engineering Theses and Dissertations

Conventional grating out-couplers in III-V waveguides typically require lengths of several hundreds of microns to outcouple 50 to 90% of the incident optical power. Enhanced coupling strength (ECS) gratings, which reduce the out-coupler grating length to tens of microns, have a large relative permittivity difference between the materials on either side of the grating boundary along with a high index cover layer. With appropriately chosen permittivity and layer thicknesses, the addition of a cover layer “pulls” the peak of the optical mode towards the grating region, resulting in a significant increase in the grating confinement factor. The resulting ECS out-coupler …

First Order Enhanced Coupling Strength (Ecs) Gratings For Laser-Electro Absorption Modulator (Eam) Transmitters, Freddie Castillo Ii

Electrical Engineering Theses and Dissertations

Conventional first-order DBR gratings in III-V waveguides often require hundreds of microns to achieve near 100% reflected power and provide narrow spectral reflectivity width for a single wavelength, limiting temperature performance of devices. Narrow reflectivity spectral width is desired for spectroscopy and wavelength division multiplexing applications where device temperature is regulated. However, Enhanced Coupling Strength (ECS) gratings provide in-plane reflectors with significantly higher reflected power per unit length, broad spectral reflectivities, and reduced losses at the waveguide-grating interface in III-V waveguides. These properties of ECS gratings allow integration of optical components such as high-speed modulators with short horizontal cavity lasers …

Method Of Making Hinged Self-Referencing Fabry–Pérot Cavity Sensors, Jeremiah C. Williams, Hengky Chandrahalim

AFIT Patents

A method is provided for fabricating a passive optical sensor on a tip of an optical fiber. The method includes perpendicularly cleaving a tip of an optical fiber and mounting the tip of the optical fiber in a specimen holder of a photosensitive polymer three-dimensional micromachining machine. The method includes forming a three-dimensional microscopic optical structure within the photosensitive polymer that comprises a two cavity Fabry-Perot Interferometer (FPI) having a hinged optical layer that is pivotally coupled to a suspended structure. The method includes removing an uncured portion of the photosensitive polymer using a solvent. The method includes depositing a …

Real-Time Complex Hand Gestures Recognition Based On Multi- Dimensional Features, Isack Bulugu

Tanzania Journal of Engineering and Technology (TJET)

Gesture recognition is broadly utilized within the field of sensing. There are basically three gesture recognition methods based on computer vision, depth sensor and motion sensor. Motion sensor-based gesture recognition has few input data, fast speed, and direct access to three- dimensional information of the hand. The advantages of traditional motion sensor-based gesture recognition have gradually become a current research hotspot. The essence of traditional motion sensor-based gesture recognition is a pattern recognition problem, and its accuracy depends heavily on the feature dataset extracted from prior experience. Unlike traditional pattern recognition methods, deep learning can be used to a large …

Economic Analysis Of Islanded Microgrid: A Case Study Of Kisiju Village - Coastal Region, Jackson Justo

Tanzania Journal of Engineering and Technology (TJET)

The concept of Microgrid (MG) has gained significant attention of researchers and projects on the business side of electrical power generation and utilization, particularly in electrification of islanded areas such as villages. Most of these microgrids are powered by renewable energy resources (RERs) and they distribute power in low voltage distribution networks. Hence, these systems are faced with reliability problems due to the intermittency nature of RERs which affect the technical as well as the return on Investment of specific projects. In the latter context, reliability and economic analysis of the MG systems is an inevitable choice. This paper presents …

Complete Neighbourhood Search Heuristic Algorithm For Portfolio Optimization, Collether John

Tanzania Journal of Engineering and Technology (TJET)

In portfolio optimization, the fundamental goal of an investor is to optimally allocate investments between different assets. Mean-variance optimization methods make unrealistic assumptions to solve the problem of optimal allocation. On the other hand, when realistic constraints like holding size and cardinality are introduced it leads to optimal asset allocation which differ from the mean variance optimization. The resulting optimization problem become quite complex as it exhibits multiple local extrema and discontinuities. Heuristic algorithms work well for the complex problem. Therefore, a heuristic algorithm is developed which is based on hill climbing complete (HC-C). It is utilized to solve the …

Design And Fabrication Of A Low-Cost, Portable, Battery-Operated Surface Enhanced Raman Scattering (Sers) Optical Device, Blessing Adewumi

LSU Doctoral Dissertations

Raman Spectroscopy is a time-honored, non-invasive method for analyzing and identifying the molecular composition of materials. However, unenhanced Raman Spectroscopy has extremely low sensitivity which limits its sensing capability. SERS brings rough nano-metallic surfaces in contact with the material molecules to enormously enhance the Raman signals.

The sensitivity of SERS can be exploited in probe applications where the spectrometer needs to be brought near the specimen. For example, a long optical fiber coupled to a SERS device can be used to characterize and identify easy-to-reach cancerous tissues in organisms. Unfortunately, background signals in a long fiber can easily mask any …

Study The C-V Behavior Of Cesium-Lead Halides Perovskite Solar Cells Under Various Simulation Parameters, Zahraa Ismail, Eman Farouk Sawires, Fathy Zaki Amer, Sameh O. Abdellatif Dr

Electrical Engineering

Capacitance response of perovskite solar cells (PSCs) can be oppressed to deduce underlying physical mechanisms, both in the materials at external interfaces and in bulk materials. Accordingly, this paper investigates the Capacitance-Voltage (C-V) characteristic curves of cesium lead halides (CsPbX3: X = I, Br, or Cl) used as an active layer in PSCs. The SCAPS-1D simulator harnessed the actual device (CsPbX3: X = I Br, or Cl) with material parameters from previous experimental work. Three main simulation parameters were investigated: the thickness of the active layer, the doping, and the defects impacts.

Investigating The Capacitive Properties Of All-Inorganic Lead Halides Perovskite Solar Cells Using Energy Band Diagrams, Zahraa Ismail, Eman Farouk Sawires, Fathy Zaki Amer, Sameh Osama Abdellatif Dr

Electrical Engineering

Capacitance response of perovskite solar cells (PSCs) can be oppressed to deduce underlying physical mechanisms, both in the materials at external interfaces and in bulk materials. Accordingly, this paper investigates the Capacitance-Voltage (C-V) characteristic curves of cesium lead halides (CsPbX3: X = I, Br, or Cl) used as an active layer in PSCs. The SCAPS-1D simulator was used to harness the actual device (CsPbX3: X = I Br, or Cl) with material parameters from previous experimental work. The energy-band diagrams, J-V curves, and C-V curves of the three PSC structures were constructed and compared to carry out and investigate their …

Low Insertion-Loss Nanophotonic Modulators Through Epsilon-Near-Zero Material-Based Plasmon-Assisted Approach For Integrated Photonics, Mohammad Ariful Hoque Sojib

Theses and Dissertations

Electro-optic/absorption Modulators (EOM/EAMs) encode high-frequency electrical signals into optical signals. With the requirement of large packing density, device miniaturization is possible by confining light in a sub-wavelength dimension by utilizing the plasmonic phenomenon. In plasmon, energy gets transferred from light to the form of oscillation of free electrons on a surface of a metal at an interface between the metal and a dielectric. Plasmonic provides increased light-matter interaction (LMI) and thus making the light more sensitive to local refractive index change. Plasmonic-based integrated nanophotonic modulators, despite their promising features, have one key limiting factor of large Insertion Loss (IL) which …

A Computational Exploration Of The Scandate Cathode Surface, Shankar Miller-Murthy

Theses and Dissertations--Chemical and Materials Engineering

The exact surface configuration of scandate cathodes has been a point of contention for the materials community for a long time. Without proper understanding of it and the related structures and emission mechanisms, scandate cathodes remain patchy and unreliable emitters. Thus, density functional theory techniques were applied to various potential surface arrangements and found that there are several low-energy surfaces with low work functions that incorporate a scandium interlayer between tungsten and oxygen or otherwise have a scandium-on-tungsten structure. Furthermore, it was discovered that adding a monolayer of scandium directly to a tungsten surface is surprisingly favorable, thermodynamically. While none …

Laptop Recycling Case Study: Estimating The Contained Value And Value Recovery Process Feasibility Of End-Of-Life Consumer Electronics, Zebulon Hart

Theses and Dissertations--Mining Engineering

Work has been done to establish, through the development and use of novel assay techniques and analysis metrics, the contained value of a sampling of laptop computers (as an analog for myriad e-waste sources). This work has conceptualized e-waste as an alternative to geologic-origin complex metallic ores and has likewise evaluated the feasibility of value recovery from e-waste sources in a similar manner to an ore. The application of conventional and novel mineral separation techniques to e-waste recycling processes has been evaluated and positive results are demonstrated. Further, this work has demonstrated the ability to identify the presence of base …