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Diffusion-Free Back Contact Solar Cells On S-Passivated Si(100) Substrates, Guanghua Song Dec 2007

Diffusion-Free Back Contact Solar Cells On S-Passivated Si(100) Substrates, Guanghua Song

Material Science and Engineering Dissertations - Archive

A diffusion-free back contact solar cell is proposed in this work. The textured front-side of this cell is coated with ~100 nm thermal SiO2 to enhance the light trapping meanwhile reduce the surface recombination velocity (SRV). The back-side of this cell is finger-patterned, using a diffusion-free junction as its emitter region and Al-Si alloy as its base contact. The diffusion-free junction is made by a Schottky contact between low work-function metal aluminum (Al) and sulfur (S)-passivated p-type Si(100) surface. Solution-based S passivation is one of the experimental realizations of the "valence-mending concept". Previously developed MBE (molecular bean epitaxy) selenium (Se) …

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Localization Of Biliary Tree Structures By Use Of Photon Diffusion Models, Dharmendra Nadkar Dec 2007

Localization Of Biliary Tree Structures By Use Of Photon Diffusion Models, Dharmendra Nadkar

Bioengineering Theses - Archive

A novel computational methodology is proposed for the intraoperative localization of biliary tree structures by means of spectrally resolved near-infrared reflectance measurements. As these structures are embedded in fatty tissue, they cannot be visualized directly, which results in inadvertent injuries during a cholecystectomy operation. Localizing the biliary tree intraoperatively is therefore an important clinical problem. Successful clinical implementation of an imaging system which could attain this goal would reduce surgical time, improve patient safety, and minimize the risk of complications and expenses attributable to the current standard practice of intraoperative cholangiography. It is hoped that the work presented here will …

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Context-Aware Inference System To Capture Design Rationale From Legacy Mcad, Ganeshram Ramji Iyer Nov 2007

Context-Aware Inference System To Capture Design Rationale From Legacy Mcad, Ganeshram Ramji Iyer

Mechanical and Aerospace Engineering Dissertations - Archive

There exist numerous design rationale systems that convert captured information into structured design rationale while providing rationale representation and retrieval. These systems woefully neglect the design rationale that is present in legacy CAD such as 2D drawings and 3D models. The dissertation addresses the issues that arise when dealing with the capture, representation and retrieval of design rationale from the 2D legacy CAD data, specifically the non-form related data (e.g. text and symbols). A definition for design rationale in the CAD domain is presented which forms the basis of the proposed approach. The approach uses a unique context-aware inference system …

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Characterization Of Rf Propagation In Metal Pipes For Passive Rfid Systems, Darmindra Danaraj Arumugam Nov 2007

Characterization Of Rf Propagation In Metal Pipes For Passive Rfid Systems, Darmindra Danaraj Arumugam

Electrical Engineering Theses - Archive

In this paper we collect and extend the theory of radio frequency (RF) propagation as it relates to propagation within metal cylinders, or circular pipes. This work is motivated by a need to understand the operation of UHF radio frequency identification (RFID) systems when the tags are placed within the pipes. These circular pipes are shown to be similar to metal tube waveguides which are either hollow or filled with air. We derive the Bessel function that is used to identify the propagation constants, the different transverse electric and transverse magnetic modes, cut-off frequencies and the multi-mode attenuation. The cut-off …

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Investigation Of Power System Blackouts And Reliability Improvement For Power Distribution Systems, Hui Zheng Nov 2007

Investigation Of Power System Blackouts And Reliability Improvement For Power Distribution Systems, Hui Zheng

Electrical Engineering Dissertations - Archive

Modern power systems often consist of thousands of equipments, each of which may have an affect on the security of the system. The trend toward deregulation has forced utilities to operate their systems closer to security boundaries [1]. This has fueled the need of faster and more accurate methods of reliability and security assessment. Power system reliability is defined as the probability that the power system will perform the function of delivering electric power to customers adequately on a continuous basis and with an acceptable quality [2]. Power system security assessment deals with the system’s ability to continue to provide …

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Wireless Devices For Medical Applications, Thermpon Ativanichayaphong Nov 2007

Wireless Devices For Medical Applications, Thermpon Ativanichayaphong

Electrical Engineering Dissertations - Archive

The deployment of medical electronics in healthcare plays a significant role to overcome many problems in disease treatment and diagnosis. For advanced applications, wireless solutions are preferred. The wireless technologies offer a new dimension of therapy or diagnosis, when wires are often bulky, unsafe, uncomfortable or even impossible to be deployed in some circumstances. The wireless communication devices can be categorized into two groups, active and passive, depending on the power sources operating electronics. The active devices draw powers from a battery, while the others harvest powers from external or internal sources. In this work, two medical applications are studied …

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Distinct Value Estimation By Sampling On Unstructured Peer To Peer Networks, Zubin Matthew Joseph Nov 2007

Distinct Value Estimation By Sampling On Unstructured Peer To Peer Networks, Zubin Matthew Joseph

Computer Science and Engineering Theses - Archive

Peer-to-Peer networks have become very popular on the Internet, with millions of peers all over the world sharing large volumes of data. The sheer scale of these networks has made it difficult to gather statistics that could be used for building new features. This thesis presents a technique of obtaining estimations of the number of distinct values matching a query on the network. The method is then analyzed by considering simulation results that demonstrate its effectiveness and flexibility in supporting a variety of queries and applications.

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Comparison Of Distributed Versus Lumped Hydrologic Simulation Models Using Stationary And Moving Storm Events Applied To Small Synthetic Rectangular Basins And An Actual Watershed Basin, Michael Jay Shultz Nov 2007

Comparison Of Distributed Versus Lumped Hydrologic Simulation Models Using Stationary And Moving Storm Events Applied To Small Synthetic Rectangular Basins And An Actual Watershed Basin, Michael Jay Shultz

Civil Engineering Dissertations - Archive

The purpose of this investigation is to compare simulations using several artificial rectangular basins and a real drainage basin for distributed and lumped hydrologic models via results obtained with the U.S. Geological Survey Modular Modeling System (MMS). Impervious watershed conditions were assumed for each simulation. A critical objective of this investigation is to assess the performance of a physically-simple lumped model compared to a more physically-complex distributed model for various storm events. Knowledge gained from this investigation may be applied to the practical problem of determining when either a distributed or lumped model may be expected to function well given …

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High Grade Control Of Linear Induction Motor Drives, Haidong Yu Nov 2007

High Grade Control Of Linear Induction Motor Drives, Haidong Yu

Electrical Engineering Dissertations - Archive

Linear induction machines (LIM) have been widely utilized in military, transportation, aerospace due to the impressive advantages such as simple configuration, easy maintenance and high acceleration/deceleration. However, the existence of trailing eddy current effect and magnetic asymmetry effect undermines the expected functionality of vector control even though LIM inherent similarities from its rotary counterpart. As a result, it has been a focal research area to either improve the performance of vector control for LIM or develop a new high grade control strategy. Therefore, the in-depth knowledge of electromagnetic behavior of LIM is necessary. From both finite element analysis (FEA) and …

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Regression Model For Prioritization Of Corridors When Retiming Traffic Signals, Manjari G. Mittal Nov 2007

Regression Model For Prioritization Of Corridors When Retiming Traffic Signals, Manjari G. Mittal

Civil Engineering Theses - Archive

Traffic signals are used by transportation engineers to safely and efficiently manage vehicle, bicycle and pedestrian traffic on roadways. However, to maintain the effectiveness of traffic signals, traffic signals should be adjusted or retimed periodically to match the current traffic patterns. Traffic signal retiming is one of the most cost effective ways available to transportation engineers for reducing delays and mitigating congestion. A region may contain a large number of traffic signals all of which cannot be retimed at once due to limited availability of funds and other resources; only a subset of signals can be retimed at any given …

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Time-Varying Feedback Systems Design Via Diophantine Equation Order Reduction, Shr-Hua Wu Oct 2007

Time-Varying Feedback Systems Design Via Diophantine Equation Order Reduction, Shr-Hua Wu

Electrical Engineering Dissertations - Archive

Diophantine equation plays an important role in the design and synthesis of feedback compensators. Many methods have been developed to solve the Diophantine equation. This dissertation develops a new systematic approach of solving a linear time-varying Diophantine equation. This approach is based upon successively reducing the order of the Diophantine equation by Euclidean algorithm. Euclidean algorithm for solving for both time-invariant and time-varying Diophantine equations for directly determining both the quotient and the remainder associated with the division of one polynomial by another is presented. The coprimeness (right or left) of two Polynomial Differential Operators is needed to guarantee, in …

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Roadside Naturalization And Texas Highway 190: A Comparison Between Best Practices And Plant Selection, John Mark Scott Sep 2007

Roadside Naturalization And Texas Highway 190: A Comparison Between Best Practices And Plant Selection, John Mark Scott

Landscape Architecture Masters & Design Theses - Archive

There is much dialog concerning the use of native plants in the roadside environment. From the Highway Beautification of Lady Bird Johnson in the 1960's to the environmental issues of today, designers are focused on ways to incorporate native plant material in the roadside. Through qualitative analysis, this thesis explores best practices for the use of native plant material in the roadside as compared with a unique roadside design in North Texas. In 2003, The North Texas Tollway Authority (NTTA) began design for the Texas Highway 190 Tollway. A new direction for roadside enhancement using native and adapted plant material …

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Medium Access Control(Mac) Layer Design And Data Query Processing For Wireless Sensor Networks, Qingchun Ren Sep 2007

Medium Access Control(Mac) Layer Design And Data Query Processing For Wireless Sensor Networks, Qingchun Ren

Electrical Engineering Dissertations - Archive

In this dissertation, there are four main aspects included: energy reservation on MAC layer, secure improvement for DoS attacks on MAC layer, query processing with uncertainty for sensor database systems, and throughput maximization on MAC layer for ultra wideband communication systems. In energy reservation, we proposed asynchronous MAC (A-MAC) protocol and asynchronous schedule-based MAC (ASMAC) protocol. A-MAC and ASMAC protocols are attractive due to their suitabilities for multihop networks and capabilities of removing accumulative clock-drifts without any network synchronization. Moreover, we build a traffic-strength- and network-density-based model to adjust essential algorithm parameters adaptively. In secure problem, we proposed a secure …

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Influence Of Codified Knowledge On Software Design Task Performance: A Comparison Of Pairs With Individuals, George Ashok Mangalaraj Aug 2007

Influence Of Codified Knowledge On Software Design Task Performance: A Comparison Of Pairs With Individuals, George Ashok Mangalaraj

Information Systems & Operations Management Dissertations - Archive

The need to improve the success rates of software development projects has prompted the software engineering community to come-up with various initiatives. These initiatives include: new software development processes such as Extreme Programming (XP), leveraging the development process by reusing existing knowledge of software artifacts. XP utilizes pairs in the performance of various software development tasks. Moreover, development of software applications is a knowledge intensive process that utilizes both tacit and explicit knowledge. This experimental study utilized software development professionals as subjects and manipulated the mode of participation (individual or pairs) and availability of codified knowledge (design patterns). Results of …

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Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager Aug 2007

Interlaminar Fracture Of Unidirectional Reinforced Composites With Toughnened Resin Systems, Aaron Slager

Material Science and Engineering Theses - Archive

Several undisclosed fiberglass and carbon fiber laminates with toughened resin systems were tested and examined. Experiments were conducted to determine Modes I and II interlaminar fracture toughness for each of the nine laminates with varying types of processing forms such as roving, tape, and slit tape of glass and carbon fibers. Fractography was then used to correlate the fracture toughness results with the unique characteristics and failure mechanisms. Overall, fiberglass laminates had larger interlaminar fracture toughness for both Modes I and II over the carbon laminates. This was also confirmed by the significant amount of the fractured surface area and …

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Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure Aug 2007

Dna Based Thin Film As Hole Transport Layer In Bulk Heterojunction Polymer Solar Cells, Vidyalakshmi Kolachure

Material Science and Engineering Theses - Archive

In the field of organic solar cell, the conjugated polymer-fullerene bulk heterojunction concept is one of the ongoing research interests. In this work, the use of de-oxyribose nucleic acid/ hexadecyl trimethyl ammonium chloride (DNA/CTMA) thin films as hole transport layer in poly(3-hexylthiophene)-methanofullerene (P3HT-PCBM) bulk heterojunction polymer solar cell is demonstrated. P3HT-PCBM bulk heterojunction polymer solar cell was fabricated with a DNA complex layer replacing commonly used PEDOT-PSS (poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS). While PEDOT-PSS, as a hole transport and electron blocking layer, often improves the solar cell performance by improving fill factor, it requires careful engineering of spin-coating for the aqueous solution of …

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Complete Stress Analysis For Two Dimensional Inclusion Problem Using Complex Variables, Rohan Arun Patil Aug 2007

Complete Stress Analysis For Two Dimensional Inclusion Problem Using Complex Variables, Rohan Arun Patil

Mechanical and Aerospace Engineering Theses - Archive

This thesis addresses the problem of finding stresses and displacements in an infinite plate with a two dimensional circular inclusion with different material properties using complex variable method with biaxial loading acting on it. The complex variable method is used so that the continuity equations of traction force and displacement field are satisfied at the interface .All the complex equations are solved using software Mathematica.

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Stress Analysis Of An Ellipsoidal Inclusion, Mahesh Kailas Aug 2007

Stress Analysis Of An Ellipsoidal Inclusion, Mahesh Kailas

Mechanical and Aerospace Engineering Theses - Archive

The focus of the present thesis is to develop a mathematical model to calculate the stresses inside an ellipsoidal inclusion present in an infinitely extended matrix region and to validate the mathematically derived model by the Finite Element Method. To this end, a theoretical model has been developed to predict the stress inside an ellipsoidal inclusion. This model is based on equivalent inclusion method used to evaluate the stress distribution theoretically. Though there have been many theories to predict the stress distribution inside an ellipsoidal inclusion, its numerical validation is new despite its importance. A finite element model of a …

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Exploratory Studies Of Convective Flows Due To Arc Tracking, Richard R. Mitchell Aug 2007

Exploratory Studies Of Convective Flows Due To Arc Tracking, Richard R. Mitchell

Mechanical and Aerospace Engineering Theses - Archive

The objective of the research was to develop an understanding of how a flame propagates through an electronic enclosure. FLUENT®, a Navier-Stokes solver, was chosen due to its widespread commercial use, the availability of turbulence models and its ability to handle combustion. The relevance of this study with respect to the aerospace and domestic appliance industry was shown through case reports. Initial observations were made on arc discharges, chemical compounds and their relevance to establishing the flame. Experimental bench tests highlighted the instigating factors for flame ignition. The first round of bench testing revealed that solder node separation played an …

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Vehicular Emissions Models Using Mobile6.2 And Field Data, Abhishek Yerramalla Aug 2007

Vehicular Emissions Models Using Mobile6.2 And Field Data, Abhishek Yerramalla

Civil Engineering Theses - Archive

Regression models to predict vehicular emissions for different categories of vehicles for different pollutants are presented in this thesis. Vehicular emissions are affected by numerous variables which, among others, include speed, temperature, acceleration, deceleration, driving behavior and meteorological data. Regression models are developed based on data obtained from Mobile 6.2 and on-board emissions measurements. The U.S. Department of Transportation (US DOT) conducted sensitivity analysis of Mobile6 where they evaluated different parameters used to find the emission factors, such as vehicle miles traveled, speed, humidity, etc. The sensitivity analysis investigated the overall Mobile6.2 model behavior for various conditions. In the analysis, …

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Large Array Emg Monitoring Of Lumbar Region Muscle Action In Discogenic Low Back Pain, Jazzmyne Ann Richardson Buckels Aug 2007

Large Array Emg Monitoring Of Lumbar Region Muscle Action In Discogenic Low Back Pain, Jazzmyne Ann Richardson Buckels

Bioengineering Theses - Archive

This project explored the use of large array surface electromyography (LASE) as a technique for assessing the patterns of muscular activity under standardized loading conditions in patients with lumbar disc related pain and healthy subjects. Specifically, the project evaluated quantitative parameters of visually observed patterns of muscle action proposed to clinically discriminate between groups. If such correlates exist, then, this work may lead to technology assessment for sensitivity and specificity as a diagnostic procedure. Solutions to the issues for determining the effects of low back pain (LBP) on force and moment generation in the spine as well as its effect …

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A Functional Analysis Of The Mechanically And Metabolically Sensitive Components Of The Skeletal Muscle Exercise Pressor Reflex In Hypertension, Anna Katherine Leal Aug 2007

A Functional Analysis Of The Mechanically And Metabolically Sensitive Components Of The Skeletal Muscle Exercise Pressor Reflex In Hypertension, Anna Katherine Leal

Bioengineering Theses - Archive

Background - In hypertension, physical activity creates a risk for adverse cardiac events by causing exaggerated increases in mean arterial pressure (MAP) and heart rate (HR). One physiological mechanism responsible for this cardiovascular hyperactivity is the exercise pressor reflex (EPR). The EPR is a neural pathway originating in skeletal muscle that contributes to cardiovascular regulation during exercise. The EPR is composed of two afferent arms: one is comprised of mostly mechanically sensitive, group III afferent fibers that respond to muscle stretch and pressure, and the other is predominantly metabolically sensitive, group IV afferent fibers that respond to the chemical milieu …

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Development Of A Broadband Multi-Channel Nirs System For Quantifying Absolute Concentrations Of Hemoglobin Derivatives And Reduced Scattering Coefficients, Dheerendra Kashyap Aug 2007

Development Of A Broadband Multi-Channel Nirs System For Quantifying Absolute Concentrations Of Hemoglobin Derivatives And Reduced Scattering Coefficients, Dheerendra Kashyap

Bioengineering Dissertations - Archive

Near infrared spectroscopy (NIRS) has been widely applied to investigate hemoglobin oxygenations of muscles, brain and breast tumors. Steady state reflectance techniques developed previously have been restricted to determination of relative concentrations. To overcome these limitations, this dissertation describes the development, validation and applications of broadband, steady-state, optical spectroscopic systems and algorithms to quantify absolute concentrations of hemoglobin derivatives and reduced light scattering coefficients using (1) thin optical probes with small (100 μm - 1 mm) source-detector separations and (2) a large separation (< 4 cm) probe.. A recently developed mathematical model by Zonios and Dimou for reflectance at small source-detector separations was used to develop techniques to quantify chromophore concentrations and light scattering coefficients (Chap. 2). Blood-intralipid phantom models were used to determine empirical coefficients to model reflectance spectra. This technique was further applied to quantify hemodynamic changes during formalin- induced pain behaviors in rats (Chap. 3). To overcome limitations in penetration depth and investigated tissue volume, another approach to quantify concentrations of chromophores in tissues at large source-detector separations was also developed. This novel approach uses the process of second differential spectroscopy to quantify concentrations of deoxygenated hemoglobin with respect to the tissue water content. Based on such quantification, an adaptation of the ant colony optimization algorithm was utilized to quantify absolute concentrations of other constituent tissue chromophores. The developed techniques were validated with the reflectance measurements from blood-intralipid phantoms and further applied to monitoring of ex vivo human prostate lesions and of rat brain tumor growth in vivo (Chap. 4). In the second stage of my doctoral development, a multi-channel, broadband, steady-state, NIRS imaging system was developed to determine spatial distributions of hemoglobin concentrations and reduced light scattering coefficients. The imager was calibrated with laboratory phantoms to eliminate deterministic instrumentation bias of CCD-spectrometers, optical fibers, and multiplexer channels. Calibration procedures also include determinations of the source strength and boundary coefficients in order to obtain accurate image reconstructions. A multi-wavelength, spectrally constrained reconstruction algorithm was developed to obtain tomographic maps of hemoglobin derivative concentrations and reduced scattering coefficients, using laboratory tissue phantoms. The developed imaging system and reconstruction algorithms were validated with both static and dynamic multi-tube phantoms.

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Resolution And Localization In Single Molecule Microscopy, Sripad Ram Aug 2007

Resolution And Localization In Single Molecule Microscopy, Sripad Ram

Bioengineering Dissertations - Archive

Rayleigh's criterion is extensively used in optical microscopy to determine the resolution of microscopes. Despite its widespread use, it is well known that this criterion is based on heuristic notions and can be surpassed in a regular optical microscope. The inadequacy of Rayleigh's criterion has necessitated a reassessment of the resolution limits of optical microscopes. The thesis proposes a new resolution criterion that overcomes the limitations of Rayleigh's criterion. The new result predicts that there is no resolution limit, but that the resolvability depends on the number of detected photons. Analytical tools are introduced to estimate the distance from microscopy …

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Spatial Resolution And Biliary Tissue Classification Properties Of A Near Infrared Light Imaging Probe, Praveen Kumar Gulaka Aug 2007

Spatial Resolution And Biliary Tissue Classification Properties Of A Near Infrared Light Imaging Probe, Praveen Kumar Gulaka

Bioengineering Theses - Archive

Approximately 500,000 Gallbladder Surgeries or Laparoscopic Cholecystectomies are performed annually to remove the Gallbladder. This surgery becomes necessary due to formation of gall stones. As biliary tract tissues are embedded in fat, differentiating them from neighboring tissues and blood vessels is critical in helping surgeons during laparoscopic cholecystectomy to avoid post-surgical complications. Optical spectroscopy (in both visible and near infrared regions) is investigated as a possible technique to identify biliary tract tissues and blood vessels. Such reflectance measurements provide information of effective attenuation, which is an index of optical properties of the tissue.Specifically, optical reflectance measurements were made on biliary …

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Experimental And Field Monitoring Studies On Recycled Materials As Pavement Bases, Sunil Kumar Sirigiripet Aug 2007

Experimental And Field Monitoring Studies On Recycled Materials As Pavement Bases, Sunil Kumar Sirigiripet

Civil Engineering Theses - Archive

Natural aggregates derived from a variety of source rocks have been used as a road base material. But the extraction of natural aggregates resources is increasingly being constrained by urbanization, increased costs and environmental concerns. Thus, increased amounts of reclaimed materials are being used to supplement natural aggregates in road construction. Recycled Asphalt Pavement (RAP) material is one of the important recycled materials used in the present geotechnical applications. Many agencies are constantly seeking to reap the benefits of utilizing RAP. Main advantages of utilizing RAP include the preservation of the existing profile, conservation of asphalt and aggregate resources, conservation …

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The Travel Behavior Of Minority Cohorts In Texas, Gustavo A. Jimenez Vera Aug 2007

The Travel Behavior Of Minority Cohorts In Texas, Gustavo A. Jimenez Vera

Civil Engineering Theses - Archive

Texas is changing dramatically; the most conservative population forecast indicates that Hispanics will account for 50% of the Texas population before 2035. Not only is the number of Hispanics on the rise in Texas, but also the foreign-born share has increased dramatically over the last 15 years. The State of Texas is now a majority minority state, and minority cohorts are expected to grow and become more than 65% of the Texas population before 2035. Transportation professionals in the State of Texas are wondering how these demographic changes will affect the transportation system. To gain an understanding of this, one …

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Cmos Vco & Lna Implemented By Air-Suspended On-Chip Rf Mems Inductors, Varun K. Shenoy Aug 2007

Cmos Vco & Lna Implemented By Air-Suspended On-Chip Rf Mems Inductors, Varun K. Shenoy

Electrical Engineering Theses - Archive

In this thesis, a CMOS 2.4 GHz Low noise amplifier (LNA) and Voltage-controlled oscillator (VCO) was designed and simulated. These circuits were designed to operate in the 2.4GHz Industrial Scientific Medicine (ISM) band and to achieve Bluetooth and Wifi standard specifications. High-Q RF MEMS air-suspended circular spiral inductors are used in both circuits. High-Q inductors give the circuit better performance parameters including higher gain, lower noise figure and narrower bandwidth. The integration of these RF MEMS inductors onto RF circuit chips was carried out using the UV-LIGA technique and an additive pattern transfer technique such as electroplating. The LNA maintains …

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Spatially Resolving Spectrometer For Characterisation Of Broad-Area Laser Diodes, Sheldon Fernandes Aug 2007

Spatially Resolving Spectrometer For Characterisation Of Broad-Area Laser Diodes, Sheldon Fernandes

Electrical Engineering Theses - Archive

The mode pattern of the BALD (Broad-Area Laser Diode) is characterized and measured using a 1-GHz resolution double-pass spectrometer. The design of spectrometer allowed also a spatial discrimination with 1mkm resolution. The construction and design of the double-pass grating is analyzed and discussed. A matrix approach is developed for the double-pass measurement arrangement. The developed procedure of analysis of spatially resolved spectra provides unique information about broad-area laser diode active medium and cavity geometry and potentially will help to predict the reliability of the laser diode. The developed model is based on paraxial approximation. The laser diode modes are measured …

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Fabrication Of A Silicon Single Electron Transistor, Sharukh Roomy Chinoy Aug 2007

Fabrication Of A Silicon Single Electron Transistor, Sharukh Roomy Chinoy

Electrical Engineering Theses - Archive

Single electronics has bright prospects because of its high scalability. The single electron transistor (SET) which utilizes these principles could replace the current workhorse of the industry, the MOSFET. The SET is plagued with limitations such as, a low operating temperature, background charge issues, a low voltage gain and high output impedance. The current generation SET devices have overcome most of the aforementioned issues but use highly complicated fabrication techniques. Electron beam lithography was used to pattern device structures on silicon-on-insulator (SOI) wafers with a hydrogen silsesquioxane (HSQ) system being the resist. The silicon was then etched using HSQ as …

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