Electronic Devices and Semiconductor Manufacturing Commons^™

An Rf Cmos Implementation Of An Adaptive Filter For Narrow-Band Interferer Suppression In Uwb Systems, Markus Both

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Ultra-wideband (UWB) technology is a new type of technology for wireless communication that is based on the transmission of low power sub-nanosecond pulses. UWB communication utilizes a large bandwidth that overlaps and is coexistent with other wireless communication standards that can be also considered as narrow-band interferers. Because UWB systems are highly susceptible to narrow-band interferers, there is a demand for interferer suppression. An adaptive filter consisting of a two-element diversity receiver that performs minimum mean square error combining (MMSE) by the LMS algorithm is proposed. Thereby the elements of the LMS algorithm as well as the receiver LNA were …

Fabrication Of Composite Nanomaterials For Thin Film Amorphous Silicon Solar Cells, Benjamin Seth Newton

Graduate Theses and Dissertations

A material with the precise combination of amorphous silicon and polycrystalline silicon would be able to take advantage of the high absorption capabilities of amorphous silicon and the electron transport capabilities of polycrystalline silicon. Polycrystalline nanostructures in the form of wires can also take advantage of other properties of light absorption, trapping and scattering inherent in nanowire structures. These properties of high absorption and electron transport in one device would lead to advances in the search for highly efficient low cost solar cells and sensors. In this work a thin film material composed of an array of polycrystalline silicon nanostructures …

Modeling And Characterization Of P-Type Silicon Carbide Gate Turn Off Thyristors, Osama Shihadeh Saadeh

Graduate Theses and Dissertations

Silicon carbide (SiC) power semiconductor devices have emerged in the past decade as the most promising technology for next generation power electronic applications ranging for electric vehicles to grid-connected power routing and conversion interfaces. Several devices have been developed, and even some have been released commercially, including diodes, MOSFETs, JFETs, thyristors, gate turn-off thyristors, and IGBTs. The model development, characterization and experimental validation of SiC p-type Gate Turn-off Thyristors (GTO) is presented in this work. The GTO device in this work is being used as part of a SiC-based solid-state fault current limiter under development at the University of Arkansas' …

In-Situ Ellipsometry Characterization Of Anodically Grown Silicon Dioxide And Lithium Intercalation Into Silicon, Eric A. Montgomery

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

In this thesis, in-situ ellipsometry and electroanalytical investigations of two electrochemical processes are reported: including the formation of anodically grown silicon dioxide and the intercalation of lithium into silicon. Analysis of the ellipsometry data shows that the anodically grown silicon dioxide layer is uniform and has similar properties as thermally grown silicon dioxide. The lithium-ion intercalation data reveals non-uniform thin film formation, which requires further studies and development of appropriate ellipsometric optical models.

Advisers: Eva Schubert and Mathias Schubert

Wavelength Dependence Of Transverse Mode Coupling With/Without E-Block Of Gan Laser Cavity, Krishneel Lal

Electrical Engineering

No abstract provided.

Full Custom Vlsi Design Of On-Line Stability Checkers, Chris Y. Lee

Master's Theses

A stability checker is a clocked storage element, much like a flip-flop, which detects unstable and late signals in the pipeline of a digital system. The On-line stability checker operates concurrently with its associated circuit-under-test (CUT). This thesis describes the full custom very-large-scale integration (VLSI) design and testing process of On-Line Stability Checkers. The goals of this thesis are to construct and test Stability Checker designs, and to create a design template for future class projects in the EE 431 Computer-Aided Design (CAD) of VLSI Devices course at Cal Poly.

A method for concurrent fault testing called On-line Stability Checking …

Structural, Electrical And Thermoelectric Properties Of Chromium Silicate Thin Films, Makram Abd El Qader

UNLV Theses, Dissertations, Professional Papers, and Capstones

Thermoelectric devices can generate electrical power as a result of their ability to produce electrical currents in the presence of thermal gradients. They can also produce refrigerative cooling when electrical power is supplied to them. Among the potential semiconducting silicides, CrSi ₂ is attractive because of its high thermal and chemical stability and its potential for thermoelectric application. CrSi₂ /SiO₂ thin-film structures were prepared using RF sputtering. As deposited and annealed (300°C to 600°C) thin films were characterized for their structural, electrical, and thermoelectric transport properties. As-sputtered CrSi ₂ film is amorphous at room temperature and crystallizes around …

Final Design Review: Design Of An Integrated Solar Cell Array To Power A Solar Ear Hearing Aid Battery Recharger, Christina (Chrissa) Blattner, Scott Carey, Jared Myren, Faye Siao

Materials Engineering

As the energy of fossil fuel supplies are fast depleting due to high consumptions of energy by human beings, the need for other sources of energy, such as solar energy, has become a viable option. By creating solar cell arrays the desired voltage can be generated. The overall goal of the Solar Ear project is to create an array of photovoltaic cells connected with aluminum tracings to recharge batteries that are specifically used for hearing aids. The goal embodies two main areas: the design of a processing method to connect the cells during a micro-fabrication process and the creation of …

Programmable Household Led Light Fixture, Jordan Locano

Electrical Engineering

This report details the development and construction of a LED light fixture to be used for household lighting. This document details background information, design ideas, project specifications, production, assembly, testing, and conclusions involved with this project. The goals of this project is to design and build a cost-effective replacement for traditional room lighting that can perform better and last longer than traditional methods.

Laser Cursor, Michael Liman

Electrical Engineering

A user controls a cursor on a computer screen using a laser pointer.  A camera picks up the laser pointer’s position and sends the data to the computer to move the cursor in the correct position.

Project 308: Augmented Reality Mario Kart, Joseph Abad, David Allender, Joryl Calizo, Ryan Gaspar, Gavin Lee

Computer Engineering

Mario Kart is a popular go-kart racing game developed by Nintendo. The premise of the game is simple: drive a go-kart along a racetrack and reach the finish line before the other players. What makes this game unique, however, is the inclusion of weapons, traps, and other projectiles that a player can use to gain an advantage in the race. We have taken on the challenge of not only recreating this amazing game, but using the art of Augmented Reality to fully immerse the player in the full experience. Rather than play the game on a television screen with a …

Low-Power Self-Sustaining Schedule Display, Samuel (Sam) August

Electrical Engineering

The completed project is an Amazon Kindle, powered by a USB solar charger, running a student designed program to display a weekly schedule for a faculty member.  The purpose of the project was to design a sustainable electronic schedule display for use outside a faculty office.  It was designed in the hopes that faculty members could more easily update their schedules, and possibly allow for students to schedule appointments.  The program was designed using Java and the solar-charger was designed using a solar cell, Schottky diode, and a USB to micro-B USB cable.

Experimental And Theoretical Study Of Polarization-Dependent Optical Transitions In Inas Quantum Dots At Telecommunication-Wavelengths (1300-1500 Nm), Muhammad Usman, Susannah Heck, Edmund Clarke, Peter Spencer, Hoon Ryu, Ray Murray, Gerhard Klimeck

Birck and NCN Publications

observed, in contrast to recent reports for single QDJOURNAL OF APPLIED PHYSICS 109, 104510 (2011)
The design of some optical devices, such as semiconductor optical amplifiers for telecommunication applications, requires polarization-insensitive optical emission at long wavelengths (1300–1550 nm). Self-assembled InAs/GaAs quantum dots (QDs) typically exhibit ground state optical emissions at wavelengths shorter than 1300 nm with highly polarization-sensitive characteristics, although this can be modified by the use of low growth rates, the incorporation of strain-reducing capping layers, or the growth of closely-stacked QD layers. Exploiting the strain interactions between closely stacked QD layers also affords greater freedom in the choice …

Showcase For The Advantages Of Asynchronous Vs. Synchronous Circuits, Justin Roark

Electrical Engineering Undergraduate Honors Theses

Synchronous circuits dominate the semiconductor industry, but asynchronous circuitry is becoming more popular and will continue to do so, as evidenced by the International Technology Roadmap for Semiconductors. Asynchronous circuits, when compared to synchronous circuits, display tolerance to supply voltage and temperature variation. The goal of this project is to demonstrate these two advantages. The project will compare two microcontrollers, a synchronous 8051 and an asynchronous 8031, which will both play a song under various stresses. Note that an 8031 and 8051 are the same, except for the 8051 includes an on-chip instruction memory, whereas the 8031's is off-chip. When …

Design Guide For Cmos Process On-Chip 3d Inductor Using Thru-Wafer Vias, Gary Vanackern

Boise State University Theses and Dissertations

Three-dimensional (3D) inductors using high aspect ratio (10:1) thru-wafer via (TWV) technology in a complementary metal oxide semiconductor (CMOS) process have been designed, fabricated, and measured. The inductors were designed using 500 μm tall vias with the number of turns ranging from 1 to 20 in both a wide and narrow trace width to space ratios. Radio frequency characterization was studied with emphasis upon de-embedding techniques and resulting effects. The open, short, thru de-embedding (OSTD) technique was used to measure all devices. The highest quality factor (Q) measured was 11.25 at 798MHz for a 1-turn device with a self-resonant frequency …

Self-Assembling Organic Semiconductors With Tunable Electronic Properties Based On Novel Asymmetric Phenazine And Bisphenazine, Kyoungmi Jang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Current demands in the area of organic semiconductors focus on both electronic and self-assembling properties. Particularly, one-dimensionally grown nanostructures of small organic semiconductors have drawn much attention for nanodevice fabrication. Self-assembly through various intermolecular interactions has been widely used to produce one-dimensionally grown nanostructures which can be induced by various methods such as rapid solution dispersion, a phase transfer method, vapor annealing, crystallization, and organogelation in conjunction with proper molecular design. Controlling the morphology of the nanostructures plays an important role in achieving desirable properties in optoelectronic device applications. While significant advancements have been made in developing molecular architectures for …

Shaped Mems Contact, Ronald A. Coutu Jr., Paul E. Kladitis, Robert L. Crane

AFIT Patents

A MEMS switch fabrication process and apparatus inclusive of a bulbous rounded surface movable contact assembly that is integral with the switch movable element and achieving of long contact wear life with low contact electrical resistance. The disclosed process is compatible with semiconductor integrated circuit fabrication materials and procedures and includes an unusual photoresist reflow step in which the bulbous contact shape is quickly defined in three dimensions from more easily achieved integrated circuit mask and etching-defined precursor shapes. A plurality of differing photoresist materials are used in the process. A large part of the contact and contact spring formation …

Electromagnetic Modeling And Measurement Of Adaptive Metamaterial Structural Elements, Matthew E. Jussaume

Theses and Dissertations

This document addresses two major obstacles facing metamaterial development: uncertainty in the characterization of electromagnetic field behavior in metamaterial structures and the relatively small operational bandwidth of metamaterial structures. To address the first obstacle, a method of prediction aided measurement is developed and exploited to examine the field interactions within metamaterial devices. The fusion of simulation and measurement techniques enhances the understanding of the physical interactions of fields in the presence of metamaterials. To address the second obstacle, this document characterizes the effectiveness of an adaptive metamaterial design that incorporates a microelectromechanical systems (MEMS) variable capacitor. Applying voltages to the …

Optical Metamaterial Design, Fabrication And Test, Jack P. Lombardi

Theses and Dissertations

Metamaterials, materials that make use of naturally occurring materials and designed structures to create materials with special properties not found in nature, are a fascinating new area of research, combining the fields of physics, microfabrication, and material science. This work will focus on the development of metamaterials operating in the visible and infrared which will be constructed and tested for basic optical properties. Possible applications for these materials will not be investigated. The this work will go into the fabrication and test of layered metal-dielectric structures, called layered metamaterials, as these structures hold potential for applications in advanced optical systems. …

Led Spotlight, Eric Toussaint

Electrical Engineering

This report details the development and construction of an LED spotlight useable in a theatrical or architectural setting.  In depth background information, initial design concepts, lighting instrument specifications, assembly, testing, and conclusions from results are highlighted in this document.  Project goals include efforts to support more energy efficient lighting in the arts and general lighting applications and a decrease in overall costs for energy used in all dramatic and architectural lighting applications.

Tuning Lattice Thermal Conductance By Porosity Control In Ultrascaled Si And Ge Nanowires, Abhijeet Paul, Gerhard Klimeck

Birck and NCN Publications

Porous nanowires 􏰎NWs􏰍 with tunable thermal conductance are examined as a candidate for thermoelectric devices with high efficiency. Thermal conductance 􏰎􏱆l􏰍 of porous NWs is calculated using the phonon dispersion obtained from a modified valence force field model. Porosity in the NWs break the crystal symmetry leading to the reduction in ballistic 􏱆l. 􏰐100􏰑 Si and Ge NWs show similar percentage reductions in 􏱆l for the same amount of porosity. The model predicts an anisotropic reduction in 􏱆l in SiNWs, with 􏰐111􏰑 showing the maximum reduction followed by 􏰐100􏰑 and 􏰐110􏰑 for a similar hole radius. The reduction in 􏱆l …

Charge Storage Characteristics Of Ultra-Small Pt Nanoparticle Embedded Gaas Based Non-Volatile Memory, Reginald Jeff, M Yun, B Ramalingam, B Lee, V Misra, Gregory Edward Triplett, Shubhra Gangopadhyay

Electrical and Computer Engineering Publications

Charge storage characteristics of ultra-small Pt nanoparticle embedded devices were characterized by capacitance-voltage measurements. A unique tilt target sputtering configuration was employed to produce highly homogenous nanoparticle arrays. Pt nanoparticle devices with sizes ranging from ∼0.7 to 1.34 nm and particle densities of ∼3.3–5.9 × 1012 cm−2 were embedded between atomic layer deposited and e-beam evaporated tunneling and blocking Al2O3 layers. These GaAs-based non-volatile memory devices demonstrate maximum memory windows equivalent to 6.5 V. Retention characteristics show that over 80% charged electrons were retained after 105 s, which is promising for device applications.

Reduced Auger Recombination In Mid-Infrared Semiconductor Lasers, Robert Bedford, Gregory Edward Triplett, David H. Tomich, Stephan W. Koch, Jerome Moloney, Jorg Hader

Electrical and Computer Engineering Publications

A quantum-design approach to reduce the Auger losses in two micron InGaSb type-I quantum well edge-emitting lasers is reported. Experimentally realized structures show a 3X reduction in the threshold, which results in 4.6 lower Auger current loss at room temperature. This is equivalent to a carrier lifetime improvement of 5.7 and represents about a 19-fold reduction in the equivalent “Auger coefficient.”

A Compact Physical Model For Morphology Induced Intrinsic Degradation Of Polymer Based Bulk Heterojunction Solar Cell, Biswajit Ray, Muhammad A. Alam

Birck and NCN Publications

The gradual loss of efficiency during field operation poses a fundamental challenge for economic viability of any solar cell technology. Well known examples include light-induced degradation in Si-based cell (Staebler-Wronski effect), Cu diffusion in thin film (CIGS) cell, hot-spot degradation in series connected modules, etc. Here we develop a compact model for an intrinsic degradation concern for bulk heterojunction type organic photovoltaic (BH-OPV) cells that involve continued (thermal) phase segregation of the donor-acceptor molecules leading to characteristic loss of efficiency and performance. Our approach interprets a number of BH-OPV device degradation measurements within a common framework and suggests/rationalizes intuitive routes …

Electronically Enhanced Surface Diffusion During Ge Growth On Si(100), Ali Orguz Er, Hani E. Elsayed-Ali

Physics Faculty Publications

The effect of nanosecond pulsed laser excitation on surface diffusion during the growth of Ge on Si(100) at 250 °C was studied. In situ reflection high-energy electron diffraction was used to measure the surface diffusion coefficient while ex situ atomic force microscopy was used to probe the structure and morphology of the grown quantum dots. The results show that laser excitation of the substrate increases the surface diffusion during the growth of Ge on Si(100), changes the growth morphology, improves the crystalline structure of the grown quantum dots, and decreases their size distribution. A purely electronic mechanism of enhanced surface …

Precise Control Of Highly Ordered Arrays Of Nested Semiconductor/Metal Nanotubes, Diefeng Gu, Helmut Baumgart, Kandabara Tapily, Pragya Shrestha, Gon Namkoong, Xianyu Ao, Frank Müller

Electrical & Computer Engineering Faculty Publications

Lithographically defined microporous templates in conjunction with the atomic layer deposition (ALD) technique enable remarkable control of complex novel nested nanotube structures. So far three-dimensional control of physical process parameters has not been fully realized with high precision resolution, and requires optimization in order to achieve a wider range of potential applications. Furthermore, the combination of composite insulating oxide layers alternating with semiconducting layers and metals can provide various types of novel applications and eventually provide unique and advanced levels of multifunctional nanoscale devices. Semiconducting TiO₂ nanotubes have potential applications in photovoltaic devices. The combination of nanostructured semiconducting materials …

Nano-Patterned High-Responsivity Gaas Metal-Semiconductor-Metal Photodetector, Ayman Karar, Chee Leong Tan, Kamal Alameh, Yong Tak Lee

Research outputs 2011

In this paper, we use the finite difference time-domain (FDTD) method to optimize the light absorption of an ultrafast nano-grating plasmonic GaAs metal-semiconductor-metal photodetector (MSM-PD) employing double metal nano-gratings. The geometry of the MSM-PD is theoretically investigated, leading to improved light absorption near the design wavelength of GaAs due to plasmon-assisted electric and magnetic field concentration through a subwavelength aperture. Simulation results show up to 8- and 21-times light absorption enhancement for the single and double nano-grating structure, respectively, in comparison to conventional MSM-PDs. Experimentally, more than 4 times enhancement in photocurrent is demonstrated for a single top nano-grating MSM-PD …