Electronic Devices and Semiconductor Manufacturing Commons^™

Development And Demonstration Of A Field-Deployable Fast Chromotomographic Imager, Daniel C. O'Dell

Theses and Dissertations

A field deployable hyperspectral imager utilizing chromotomography (CT), with a direct vision prism (DVP) as the dispersive element, has been constructed at AFIT. This research is focused on the development and demonstration of the CT imager. An overview of hyperspectral imaging, chromotomography, a synopsis of reconstruction algorithms, and other CT instruments are given. The importance of component alignment, instrument calibration, and exact prism angular position data are discussed. A simplistic \shift and add" reconstruction algorithm was utilized for this research. Although limited in its ability to reconstruct a spatially and spectrally diverse scene, the algorithm was adequate for the testing …

Wi-Fi Evapotranspiration Irrigation Controller, Ryan Goodman

Electrical Engineering

This report discusses the applications of an Irrigation Controller with Wi-Fi connectivity, with focus on cost-effectiveness and usability. It addresses the amount to which traditional irrigation is wasteful, and proposes solutions to solve this problem. Methods for using online weather data resources to increase efficiency of residential landscaping are discussed in depth. Included is the procedural development of an irrigation controller using the Microchip Explorer 16 Development Board and TCP/IP Stack. Also discussed is web hosting and use of the scripting language PHP, and database MySQL. This project found inexpensive means for providing HTTP and FTP services. Results indicate an …

Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, Pradeep R. Nair, Muhammad A. Alam

Birck and NCN Publications

Modern label-free biosensors are generally far more sensitive and require orders of magnitude less incubation time compared to their classical counterparts. However, a more important characteristic regarding the viability of this technology for applications in Genomics/Proteomics is defined by the ‘Selectivity’, i.e., the ability to concurrently and uniquely detect multiple target biomolecules in the presence of interfering species. Currently, there is no theory of Selectivity that allows optimization of competing factors and there are few experiments to probe this problem systematically. In this article, we use the elementary considerations of surface exclusion, diffusion limited transport, and void distribution function to …

Nano-Scaled Fet Device For Cmos Technology, Prabhat Ranjan Pathak

Dissertations

In this work the 3-D structure of the Accumulation mode (ACM) and Enhance mode (ECM) FinFET was developed by the Taurus-Device Editor. The design of both ACM and ECM FinFET was optimized for high-performance IC applications to meet ITRS specification for I_off current, for 9nm gate length. The design of ACM and ECM FinFET is optimized, analyzed and compared against each other with respect to Darin Induced Barrier Lower (DIBL), Sub-threshold Swing(SS), operation and performance characteristics with varying electrical and physical parameters Silicon thickness (T_si), Source/Drain doping gradient (σ_sd), electrical channel length (L_eff ), …

Production Of Multiwall Carbon Nanotube For Alcohol Sensor Application., Ebtehal Saleh Alshaqaq

Student Works (2010-2019)

Multiwall carbon nanotube/polyethylene oxide (PEO), multiwall carbon nanoube/polyvinyl alcohol(PVA) and multiwall carbon nanotube/ polyvinyl alcohol(PVA)/zinc oxide(ZnO) have been tested as chemical sensors and detailed study on the effect of different gas concentration and material properties on gas sensitivity is presented. Initial composites were prepared by a simple solution casting and characterized by x-ray diffraction for ZnO, Fourier transform infra-red spectroscopy (FTIR) and scanning electron microscopy (SEM) to demonstrate crystallite size of ZnO, the morphology and surface area respectively. On the other hand, MWCNT/PEO , MWCNT/PVA , MWCNT/PVA/ZnO were prepared with different loading MWCNT and ZnO. The chemical sensing properties of …

Inductively Coupled Plasma Dry Etching Process On Planar Lightwave Circuit Fabrication., Chuah Khoon Seah

Student Works (2010-2019)

The main objective of this project is to master state-of-the-art techniques and knowledge in silica etching in order to achieve high quality waveguide circuit on Planar Lightwave Circuit devices. Another objective is to optimize the clean room research strength, surface characterization, microscopy techniques and similar semiconductor manufacturing processes.Initially, these processes were conducted with wet etching method that utilized diluted hydrofluoric acid (HF) and buffered oxide etch (BOE). Several problems arising such as mask peel-off, poor sidewall profile and defect waveguide channel during the pattern transfer process due to its’ isotropic nature. Alternatively, dry etching method was conducted via Inductively Coupled …

Excitation-Induced Germanium Quantum Dot Formation On Si (100)-(2×1), Ali Oguz Er, Hani E. Elsayed-Ali

Physics Faculty Publications

The effect of nanosecond pulsed laser excitation on the self-assembly of Ge quantum dots grown by pulsed laser deposition on Si (100)-(2×1) was studied. In situ reflection high-energy electron diffraction and ex situ atomic force microscopy were used to probe the quantum dot structure and morphology. At room temperature, applying the excitation laser decreased the surface roughness of the grown Ge film. With surface electronic excitation, crystalline Ge quantum dots were formed at 250 °C, a temperature too low for their formation without excitation. At a substrate temperature of 390 °C, electronic excitation during growth was found to improve the …

Optimization Of Inductively Coupled Plasma Dry Etching For Planar Waveguide Fabrication., Lim Weng Hong

Student Works (2010-2019)

Optimization of the Inductively Coupled Plasma (ICP) dry etching process parameters has been carried out. Seven main etching characteristics were considered in order to produce good etching quality. These characteristics are glass etching rates, selectivity of chromium to glass etching rate, channel side wall roughness, channel side wall vertical profile, channel cleanliness, critical dimension and resolution. Several ICP parameters that are affecting the etching characteristic were optimized in this work. These optimised ICP parameters obtained from this work are ICP power (880 W), bias power (45 W), operating chamber pressure (10 mtorr), reactant gas composition, reactant gas flow rate (35sccm …

Giant Raman Enhancement On Nanoporous Gold Film By Conjugating With Nanoparticles For Single-Molecule Detection, Lihua Qian, Biswajit Das, Yan Li, Zhilin Yang

Electrical & Computer Engineering Faculty Research

Hot spots have the contradictively geometrical requirements for both the narrowest interstices to provide strong near-field coupling, and sufficient space to allow entrance of the analytes. Herein, a two-step method is employed to create hot spots within hybrid nanostructures, which consist of self-supported nanoporous gold films with the absorbed probes and subsequent nanoparticle conjugates without surface agents or mechanical motion. The molecules confined into 1 nm interstice exhibit 2.9 × 10⁷ times enhancement in Raman scattering compared to pure nanoporous gold. Giant enhancement primarily results from strong near-field coupling between nanopore and nanoparticle, which is theoretically confirmed by finite-difference …

Growth And Characterization Of Silicon Carbide Thin Films Using A Nontraditional Hollow Cathode Sputtering Technique, James Huguenin-Love

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

Silicon carbide (SiC) is considered a suitable candidate for high-power, high-frequency devices due to its wide bandgap, high breakdown field, and high electron mobility. It also has the unique ability to synthesize graphene on its surface by subliming Si during an annealing stage. The deposition of SiC is most often carried out using chemical vapor deposition (CVD) techniques, but little research has been explored with respect to the sputtering of SiC.

Investigations of the thin film depositions of SiC from pulse sputtering a hollow cathode SiC target are presented. Although there are many different polytypes of SiC, techniques are discussed …

Passivation Of Polymer Light-Emitting Diodes, Stephen A. Fehrman

Electrical Engineering

This senior project investigates various methods of packaging polymer LEDs. The polymer LEDs fabricated in the EE 422 Polymer Electronics lab use calcium cathodes. While calcium acts as an excellent low work function electrode, it quickly oxidizes in the presence of oxygen or water. Additionally, the intrusion of water can degrade the OC1C10-PPV electroluminescent polymer and the PEDOT polymer. Therefore, in order to use these devices outside the inert atmosphere of a glove box, we must first apply a passivation layer that inhibits the deterioration of these materials.

For this project I will test two packaging methods. The first method …

Pic Controlled Two-Band Stereo Audio Equalizer, Tim Brown

Electrical Engineering

The purpose of this project is to build a PIC (Peripheral Interface Controlled) controlled two-band stereo audio equalizer. The input audio from each stereo channel is separated into four different analog filters. The PIC has been programmed in BASIC and is used to route the audio signal to one of the four analog filters. Three of the filters have been preset to a certain frequency response (Jazz, Natural, and Bass), and the fourth filter has the unique ability to be controlled manually. Stereo potentiometers have been installed on the “Manual” filter to allow the user to change the frequency response …

Dc-Dc Converter For Harvesting Energy From An Exercise Bike, Henry Ureh, Chris Henry

Electrical Engineering

Create an efficient buck-boost converter that adapts to input voltage range from ~3.8V to 70V, and outputs 13.7V DC, the voltage required by a charge controller to charge a battery. The energy stored in the battery will be supplied back to the grid.

The cost of energy saved by the converter should eventually cover the initial price of the converter. The converter should help reduce the net power consumption of the exercise machines used in the Cal Poly gym

X-Ray Photoemission Analysis Of Chemically Treated Gate Semiconductor Surfaces For Radiation Detector Applications, A. J. Nelson, A. M. Conway, B. W. Sturm, E. M. Behymer, C. E. Reinhardt, R. J. Nikolic, S. A. Payne, G. Pabst, K. C. Mandal

Faculty Publications

No abstract provided.

A New Control Method For Input-Output Harmonic Elimination Of The Pwm Boost-Type Rectifier Under Extreme Unbalanced Operating Conditions, Ana Vladan Stankovic, Ke Chen

Electrical and Computer Engineering Faculty Publications

Under severe fault conditions in the distribution system, not only input voltages but also input impedances must be considered as unbalanced. This paper presents a new control method for input-output harmonic elimination of the pulsewidth-modulation (PWM) boost-type rectifier under conditions of both unbalanced input voltages and unbalanced input impedances. The range of imbalance in both input voltages and input impedances, for which the proposed method is valid, is analyzed in detail. An analytical approach for complete harmonic elimination shows that PWM boost-type rectifier can operate at unity power factor under extremely unbalanced operating conditions resulting in a smooth (constant) power …

Advanced Thermosonic Wire Bonding Using High Frequency Ultrasonic Power: Optimization, Bondability, And Reliability, Minh-Nhat Ba Le

Master's Theses

Gold wire bonding typically uses 60 KHz ultrasonic frequency. Studies have been reported that increasing ultrasonic frequency from 60KHz to 120KHz can decrease bonding time, lower bonding temperature, and/or improve the bondability of Au metalized organic substrates. This thesis presents a systematic study of the effects of 120 KHz ultrasonic frequency on the reliability of fine pitch gold wire bonding. Two wire sizes, 25.4 and 17.8 μm in diameter (1.0 and 0.7 mil, respectively) were used. The gold wires were bonded to metalized pads over organic substrates with five different metallization. The studies were carried out using a thermosonic ball …

Analysis & Design Of Improved Multiphase Interleaving Dc-Dc Converter With Input-Output Bypass Capacitor, Rudi Rudianto

Master's Theses

As the transistor count per chip in computer microprocessors surpasses one billion, the semiconductor industry has become more and more concerned with meeting processor’s power requirements. This poses a design challenge for the power supply module, especially when the processor operates at low voltage range. For example, the electrical requirement for the newest Intel microprocessors has exceeded 100A with an input voltage of approximately 1V. To overcome this problem, multiphase DC-to-DC converters encased in a voltage regulator module (VRM) have become the standard means of supplying power to computer microprocessor.

This study proposes a new topology for the multiphase DC-to-DC …

Low Voltage, Low Power, Bulk-Driven Amplifier, Shama Huda

Electrical Engineering Undergraduate Honors Theses

The importance of low voltage and low powered electronics is increasing with advances in medical electronics. This branch of electronics specifically requires low voltage and low power to make efficient innovative medical equipment. Low power electronics are also desirable because it conserves energy and power. This paper proposes a design of a differential in - differential our amplifier that uses a bulk-driven differential pair for the input pair. In addition, it also used bulk-driven current mirrors for the tail current sink and the active loads. The bulkdriven technique helps to achieve the low voltage design. 90nm CMOS technology was considered …

Drive-Mode Control For Vibrational Mems Gyroscopes, Lili Dong, David Avanesian

Electrical and Computer Engineering Faculty Publications

This paper presents a novel design methodology and hardware implementation for the drive-mode control of vibrational micro-electro-mechanical systems gyroscopes. Assuming that the sense mode (axis) of the gyroscope is operating under open loop, the drive-mode controller compensates an undesirable mechanical spring-coupling term between the two vibrating modes, attenuates the effect of mechanical-thermal noise, and most importantly, forces the output of the drive mode to oscillate along a desired trajectory. The stability and robustness of the control system are successfully justified through frequency-domain analysis. The tracking error between the real output and the reference signal for the drive mode is proved …

Micro-Scale Flapping Wings For The Advancement Of Flying Mems, Nicholas R. Coleman

Theses and Dissertations

This research effort presents conceptual micro scale air vehicles whose total dimensions are less than one millimeter. The initial effort was to advance the understanding of micro aerial vehicles at sub-millimeter dimensions by fabricating and testing micro scale flapping wings. Fabrication was accomplished using a surface micromachining process called PolyMUMPs™. Both rigid mechanical structures and biomimetic devices were designed and fabricated as part of this effort. The rigid mechanical structures focused on out of plane deflections with solid connections and assembling a multiple hinge wing structure through the aid of residual stress. These devices were actuated by double hot arm …

Optimization Of Gan Laser Diodes Using 1d And 2d Optical Simulations, Sean Richard Keali'i Jobe

Master's Theses

This paper studies the optical properties of a GaN Laser Diode (LD). Through simulation, the GaN LD is optimized for the best optical confinement factor. It is found that there are optimal thicknesses of each layer in the diode that yield the highest optical confinement factor. There is a strong relationship between the optical confinement factor and lasing threshold—a higher optical confinement factor results in a lower lasing threshold. Increasing optical confinement improves lasing efficiency. Blue LDs are important to the future of lighting sources as they represent the final color in the RGB spectrum that does not have a …

A Mems Multi-Cantilever Variable Capacitor On Metamaterial, Luke A. Rederus

Theses and Dissertations

Negative refractive index materials are an example of metamaterials that are becoming increasingly popular. Research into these metamaterials could possibly be the first steps toward bending electromagnetic radiation (i.e., microwaves, light, etc.) around an object or person. Split ring resonators (SRR) are classified as metamaterials that create an artificial magnetic response from materials with no inherent magnetic properties. Once fabricated, an SRR has a specific resonant frequency due to its permanent geometry. This research introduces a new concept of using a variable capacitive micro- electro-mechanical system (MEMS) device located at the gap of an SRR to mechanically alter the capacitance …

Model For Alumina Nanopore-Based Optical Filter, Nathan Lehman, Rama Venkat, Robert A. Schill

Electrical & Computer Engineering Faculty Research

Alumina nanopore structures find applications in magnetic sensors, optical filters, and various biological devices. In this work, we present a ray-optics model for the optical filter. We present a detailed simulation and a simplified analytical expression for the reflectance as a function of the alumina parameters such as pore diameter, pore density, alumina thickness, and a function of the wavelength and angle of incidence of the illuminating plane electromagnetic wave. The reflectance vs wavelength in the range of 400–800nm obtained from the simulation and the analytical expression are compared with that of the experiments for thin and thick alumina. All …

Low-Temperature Growth Of Inn On Si(100) By Femtosecond Pulsed Laser Deposition, M. A. Hafez, H. E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

InN films were grown on Si(100) using femtosecond pulsed laser deposition. Laser induced breakdown of ammonia was used to generate atomic nitrogen for InN growth. An indium buffer layer was initially deposited on the Si substrate at low temperature followed by an InN intermediate layer. The crystal quality and surface morphology were investigated by reflection high-energy electron diffraction during growth and atomic force microscopy and x-ray diffraction after growth. The results showed that the In (2×1) initial buffer layer improved the quality of the InN film. High quality InN films were grown at a temperature of ∼350 °C.

On Control System Design For The Conventional Mode Of Operation Of Vibrational Gyroscopes, Lili Dong, Qing Zheng, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

This paper presents a novel control circuitry design for both vibrating axes (drive and sense) of vibrational gyroscopes, and a new sensing method for time-varying rotation rates. The control design is motivated to address the challenges posed by manufacturing imperfection and environment vibrations that are particularly pronounced in microelectromechanical systems (MEMS) gyroscopes. The method of choice is active disturbance rejection control that, unlike most existing control design methods, does not depend on an accurate model of the plant. The task of control design is simplified when the internal dynamics, such as mechanical cross coupling between the drive and sense axes, …

A Systematic Study On Structural And Optical Properties In Conjugated Polymer Photovoltaic Devices, Sri Sabarinadh Sunkavalli

Electrical & Computer Engineering Theses & Dissertations

Conjugated polymer/fullerene based solar cells represent an exciting alternative to inorganic ones because of their low production costs, flexibility and low weight. At present, commercialization of organic photovoltaic (OPV) cells is limited due to their relatively low efficiency in comparison to silicon ones. In order to understand the operation of OPV cells and to increase their efficiency, more information about the structure of the absorber layer is needed. In particular, the connection between structure and properties of the absorber layer is of great importance. Performance of bulk heterojunction organic solar cells based on poly (3-hexylthiophene) as donor and a soluble …

Hand-Held Flyback Driven Coaxial Dielectric Barrier Discharge: Development And Characterization, Victor J. Law, Vladimir Milosavljevic, Neil O’Connor, James F. Lalor, Steven Daniels

Articles

The development of a handheld single and triple chamber atmospheric pressure coaxial dielectric barrier discharge driven by Flyback circuitry for helium and argon discharges is described. The Flyback uses external metal-oxide-semiconductor field-effect transistor power switching technology and the transformer operates in the continuous current mode to convert a continuous dc power of 10–33 W to generate a 1.2–1.6 kV 3.5 μs pulse. An argon discharge breakdown voltage of ∼768 V is measured. With a 50 kHz, pulse repetition rate and an argon flow rate of 0.5–10 argon slm (slm denotes standard liters per minute), the electrical power density deposited in …

Measurement Of Absolute Argon Excited State Populations And Electron Energy Distribution Functions In An Ar-A-Si Plasma, Katherine Herring

Electrical Engineering Undergraduate Honors Theses

Deposition systems utilizing plasma are used for a variety of tasks, including tool coatings and creating thin-film materials. In order to have repeatable results, the internal conditions of a plasma chamber need to be known. This project centered on the use of data from optical emissions and a Langmuir probe from an argon plasma amorphous silicon depositing system. An electron energy distribution function (EEDF) was obtained from manipulation of the Langmuir probe data. This EEDF was then input to an argon collisional-radiative model (CRM) to obtain the electron population of the 4p level of the argon plasma. Through an absolute …

A Timer Module For An 8051 Microcontroller, Troy England

Electrical Engineering Undergraduate Honors Theses

A timer module for an 8051 Microcontroller is designed from the ground up. It could potentially be integrated into a larger 8051 for use in lunar and Martian missions. It follows through a synchronous digital design flow from HDL code through layout verification. The timer shows functionality at 100MHz with some minor glitches.

Real-Time Plasma Controlled Chemistry In A Two-Frequency, Confined Plasma Etcher, Vladimir Milosavljevic, Albert R. Ellingboe, Cezar Gaman, John V. Ringwood

Articles

The physics issues of developing model-based control of plasma etching are presented. A novel methodology for incorporating real-time model-based control of plasma processing systems is developed. The methodology is developed for control of two dependent variables (ion flux and chemical densities) by two independent controls (27 MHz power and O2flow). A phenomenological physics model of the nonlinear coupling between the independent controls and the dependent variables of the plasma is presented. By using a design of experiment, the functional dependencies of the response surface are determined. In conjunction with the physical model, the dependencies are used to deconvolve the sensor …