Document 01


Summer Research Experience for Undergraduates (REU)
	2002 Summer Abstracts
	Carlos Juan Marrero - iSCSI Performance Measurement & Comparison Hilary Flinkstrom - Electrokinetic Generator Devon Skyllingstad and Heather Metcalf - Implicit Communication Aiding in Search and Retrieval Amongst Homogeneous Autonomous Robots Jose Aguas Bonfil - Extraction of Impurities by C-V characteristics Kathleen McGill - Magnetostrictive Nanostructures Jeremy Brown - Adapting the SPEC 2000 Benchmark Suite for Simulation-Based Computer Architecture Research Amy E. Parker - Utilizing Smart Materials for Voltage Generation and Actuation Purposes Tracy J. Mayer - Novel Transparent Conducting Contacts for Solar Cells Zhongning Chen - Lightweight, low-cost INS/GPS Strapdown System Patrick McGary - Integrated Waveguide Isolators Samantha Livingston - SPICE-Matlab Interface Jason Hsung - Nanotechnology Kjersti Kleven - Substrate Etching in Coupled Microstrip Lines Nick Miller - Modeling Photonic Band Gap Structures Using Ansoft-High Frequency Structure Simulator Eldon Nelson - Designing a DMA Controller for the Motorola 68HC12 Microcontroller Seth Thomas Sweep - JBits and Java as an Interface for Field Programmable Gate Arrays
2002 Summer Program Staff
Professor Douglas Ernie	Steve Seehugen Program Assistant	Professor Bethanie Stadler
2002 Summer Program Abstracts
	Participant: Carlos Juan Marrero Home Institution: University of Puerto Rico - Mayagüez Campus Faculty Mentor: Dr. David Du Project: iSCSI Performance Measurement & Comparison The Internet SCSI (iSCSI) protocol defines a new way for mapping block-oriented data over TCP/IP networks. SCSI enables systems to perform data Input/Output (I/O) operations with a variety of peripheral devices such as disk, tape and optical storage devices, as well as printers and scanners. The traditional SCSI connection between a host system and peripheral devices has distance and device support limitations. With the development of network-based technologies such as Fibre Channel and Gigabit Ethernet and the reliability of TCP/IP networks, such restrictions are conquered. Combining these two protocols into one, the iSCSI protocol enables universal access to storage devices and storage-area networks (SANs) over standard Ethernet-based networks. The main objective of this project is to study the performance of the block-level data access over an actual iSCSI setup using a test code developed for Windows 2000 platform.
	Participant: Hilary Flinkstrom Home Institution: University of Maine, Orono Faculty Mentor: Professor Babak Ziaie Project: Electrokinetic Generator A pacemaker is one example of an implantable medical device that uses batteries that periodically need to be recharged or replaced; a procedure that requires surgery. My team has been studying the possibility of using voltages available in the body to power such devices, eliminating the need for surgery. Our research relies on the fact that when a pressure is introduced across a small capillary a potential difference appears. This is an example of an electro-kinetic phenomenon.
	Participants: Devon Skyllingstad and Heather Metcalf Home Institution: Xavier University, Clarion University of Pennsylvania Faculty Mentor: Dr. Maria Gini Project: Implicit Communication Aiding in Search and Retrieval Amongst Homogeneous Autonomous Robots The minDART (Minnesota Distributed Autonomous Robotics Team) uses robots to implement a task of search and retrieval in which the goal is to locate, collect, and return targets to a home base. Our homogenous robots had previously performed these tasks independently, using localization without communication for target search and retrieval. This tactic, while effective, was not efficient. Through our work this summer, the robots now implicitly communicate with each other through the use of beacons and cameras. This communication decreases the time for localization as well as the recovery of targets.
	Participant: Jose Aguas Bonfil Home Institution: University of Minnesota Faculty Mentor: Ted K. Higman, Ph.D Project: Extraction of Impurities by C-V characteristics The metal oxide(SiO2)-semiconductor(Si) or MOS structure is the essential structure for modern-day microelectronics. A more general term, which includes other insulators and semiconductors rather than SiO2 and Si is metal-insulator-semiconductor. The simplest way to find fundamental characteristics of the MIS is through the two-terminal MIS-capacitor(MIS-C.) The insulator sandwich between the metallic plate and the substrate contact forms a capacitor. The capacitance-voltage(C-V), voltage applied to the metal gate, displays some of the important characteristics to analyze internal properties of the MIS-C. The capacitance seen by the MIS-C is dc-bias dependent as opposed to a regular electrolytic capacitor. In the normal capacitance-voltage measurement, the dc-bias is swept from either negative to positive voltage or vice versa, depending on substrate doping while the capacitance is probed by a small signal AC excitation. The Dc sweep causes the MIS-C to go from accumulation through depletion to inversion. Ideally, one would like to see the capacitance remain constant in accumulation, decrease in depletion, and again remain constant in inversion. Due to some impurities internal to the oxide, one sees non-idealities in the MOS-C characteristics. The non-idealities can be modeled as capacitor in parallel with a conductance, in series with a contact resistance. The latter resistance is not inherently part of the MIS-C physics, but rather is the normal lumped resistance associated with making electrical contact with the device. The measurement frequencies are generally at or below 1 MHz, so series inductance can be ignored. Solving for the parameters, one gets two equations with three unknowns. One of the unknowns, the series resistance, can be calculated by making additional measurements at different frequencies since it is largely independent of frequency.
	Participant: Kathleen McGill Home Institution: Creighton University Faculty Mentor: Dr. Bethanie Stadler Project: Magnetostrictive Nanostructures Magnetostrictive materials transduce, or convert, magnetic energy to mechanical energy and vice versa. As a magnetostrictive material is magnetized, it strains; that is, it exhibits a change in length per unit length. Conversely, if an external force produces a strain in a magnetostrictive material, the material's magnetic state will change. This bi-directional coupling between the magnetic and mechanical states of a magnetostrictive material provides a transduction capability that is used for both actuation and sensing devices. This project proposes to study the fabrication of magnetostrictive devices for ultrasonic transducers, which may find application in underwater sonar, medical devices, and chemical sensors. The magnetostrictive materials will be grown by electrochemically depositing Fe and Co into nanoporous anodic alumina structures. The resulting nanofibers will be structurally and chemically characterized, using a Scanning Electron Microscope, an X-ray Diffractometer, and a Vibrating Sample Magnetometer, and measured for magnetostrictive response.
	Participant: Jeremy Brown Home Institution: West Virginia University Institute of Technology Faculty Mentor: Dr. David Lilja Project: Adapting the SPEC 2000 Benchmark Suite for Simulation-Based Computer Architecture Research The large input data sets in the SPEC 2000 benchmark suite result in unreasonably long simulation times when using detailed execution-driven simulators for evaluating future computer architecture ideas. To address this problem, we have an ongoing project to reduce the execution times of the SPEC 2000 benchmarks in a quantitatively defensible way. Upon completion of this work, we will have smaller input data sets for several SPEC 2000 benchmarks. The programs using our reduced input data sets will produce execution profiles that accurately reflect the program behavior of the full reference data set, as measured using standard statistical tests. In the process of reducing and verifying the SPEC 2000 benchmark data sets, we also obtain instruction mix, memory behavior, and instructions per cycle characterization information about each benchmark program.
	Participant: Amy E. Parker Home Institution: University of North Carolina at Charlotte Faculty Mentor: Professor William Robbins Project: Utilizing Smart Materials for Voltage Generation and Actuation Purposes Smart materials such as lead zirconate titanate (PZT) and Terfenol-D can be used in many applications. By creating a laminate composite of these two materials, a small cordless voltage supply can be created. Depending on the magnitude of the alternating field and the size of the sample a promising voltage can be created in order to drive a load. Another application being investigated in this research is a piezoelectric driven microactuator. If the new actuator design gives a large displacement, it will be developed into a peristaltic micropump to be used in microelectromechanical systems (MEMS).
	Participant: Tracy J. Mayer Home Institution: University of Wisconsin- River Falls Faculty Mentor: Professor Philip I. Cohen Project: Novel Transparent Conducting Contacts for Solar Cells Indium tin oxide (ITO) is widely used as a transparent conductor because it has high electric conductivity and high transmittance in the visible and near infrared (IR) region. Thin films of ITO can be used to make contact to high performance solar cells. The goal of the project is to improve the electrical conductivity without sacrificing optical transparency of the films. There is a mechanism that hinders electron passage in thin films of ITO, possibly caused by the tin dopant atoms which are introduced to generate mobile electrons. By producing a superlattice of alternating doped and pure In₂O₃ layers, the electrons are produced in the doped layer and will move freely into the undoped layer. In this project the oxygen partial pressure was varied while growing ITO films to find the rate at which oxygen should be introduced to produce optimum quality films. Based on the results, a superlattice of ITO and In₂O₃will be grown in order to increase the conductivity without sacrificing optical transparency, and ultimately improve the performance of solar cells.
	Participant: Zhongning Chen Home Institution: University of California, Berkeley Faculty Mentor: Professor Gary Balas Project: Lightweight, low-cost INS/GPS Strapdown System Typical lightweight, low-cost INS/GPS (Inertial Navigation System/Global Positioning System) devices currently available in the market weigh more than 5 lbs, and cost more than 20,000 dollars. The trend in the industry is towards extremely low weight (10s of grams), and low cost (about 1,000 dollars) devices. The goal for this project is to develop a single board, credit card sized, integrated INS/GPS package, which weighs less than 50 grams, and costs less than 1,000 dollars. The package consists of three gyros, three accelerometers, a 3-axis magnetometer, two pressure sensors, a communication chip, and a DSP (Digital Signal Processor) chip. The design of the package requires defining the requirements for the systems, the hardware components, algorithms and calculations needed to be performed, interface with other off-board processors, communication protocol, along with the hardware and software system design. This poster presents the preliminary hardware components of the package, INS/GPS strapdown mechanization procedure, and IMU (Inertial Measuring Unit) data processing algorithms. An example of the device application is presented.
	Participant: Patrick McGary Home Institution: Bob Jones University Faculty Mentor: Dr. Bethanie Stadler Project: Integrated Waveguide Isolators Photonic integrated circuits (PICs) are the optical equivalents of integrated circuits (ICs) where the current is carried by photons rather than electrons. This work aimed to equip PICs with important devices that are currently available only as discrete components, namely magneto-optical isolators. The current fabrication technique, liquid phase epitaxy, cannot be used with semiconductor substrates, which are important platforms for many electro-optical devices. In addition, sputtering can be used to deposit buffer layers and magnetic thin films, so device costs can be greatly reduced. To achieve integration of magneto-optical (MO) materials, several major hurtles must be overcome, including development of a low-temperature, low-cost fabrication technique, identification of suitable buffer layers, optimization of the film microstructure, and optimization of the MO and magnetic properties. The resulting films were characterized structurally, chemically, and optically, as well as measured for faraday rotation.
	Participant: Samantha Livingston Home Institution: Massachusetts Institute of Technology Faculty Mentor: Professor Jaijeet Roychowdhury Project: SPICE-Matlab Interface SPICE is an open source circuit simulation program written in C that reads in a user’s file, sets up the circuit’s equations, and does the requested analysis. This project takes the fundamental equations that characterize the circuit as outputted by SPICE and loads them into a MATLAB simulation program. By interfacing SPICE with MATLAB a program specializing in mathematical computations, a large simple circuit can be analyzed in less time.
	Participant: Jason Hsung Home Institution: University of Minnesota-Twin Cities Faculty Mentor: Dr. Heiko Jacobs Project: Nanotechnology We are positioning nanoparticles onto charged patterns, trying to achieve 100 nanometer resolution. We use photolithography or electronbeamlithography to create a mold to make a flexible stamp made out of poly(dimethalsiloxane) (PDMS). We then evaporate 80 nanometers of gold onto the stamp to make it conductive. We take a silicon chip with a thin layer of a dielectric film made out of poly(methylmethacrylate) (PMMA), put it on the PDMS stamp, and run current through the system. This exposure allows us to store charged patterns in the dielectric thin film. Now we immerse the charged pattern in a solution of nanoparticles, e.g. graphitized carbon in perfluorodecalin (PFD). The nanoparticles align to the charged patterns on the thin film of PMMA. By experimenting and improving upon our techniques, we should be able to achieve 100 nanometer resolution. The current resolution is 700 nm about 100 times the resolution of xerographic printers and copy machines.
	Participant: Kjersti Kleven Home Institution: Embry-Riddle Aeronautical University Faculty Mentor: Professor Rhonda Drayton Project: Substrate Etching in Coupled Microstrip Lines The goal of this research is to investigate methods for improving isolation between high density (i.e. closely spaced) interconnects. This work investigates the effect of substrate coupling between neighboring lines and compares these results to traditional methods that increase the lateral spacing between neighboring elements. The test circuit involved is the gap-coupled microstrip, which can be end or laterally coupled to an adjacent line. This line is a fundamental building block for the design of filters and directional couplers used in microwave applications. Because the capacitance in the gap changes as the substrate is etched out, the decoupling increases without an increase in the gap separation. This is beneficial because it allows for a more compact design without adding complexity to the fabrication process.
	Participant: Nick Miller Home Institution: Saint Cloud State University Faculty Mentor: Dr. Anand Gopinath Project: Modeling Photonic Band Gap Structures Using Ansoft-High Frequency Structure Simulator We explore the use of commercially available code to model photonic band gap structures or photonic crystals. The use of commercial code, such as Ansoft HFSS, is less time consuming and has better graphics than noncommercial code. By verifying that this code is valid for our applications, we can use it to model PBG structures in a variety of applications. The motivation for this project is to model a high contrast waveguide coated with photonic crystals. The second goal is to look at possible uses of this coating to reduce radar cross sections of large objects. By verifying the code for some simple cases, we can be confident that the program will handle the complicated models that we aim to solve. It has been shown that Ansoft’s HFSS accurately solves dialectric sphere scattering problems and is also able to handle periodic boundary conditions.
	Participant: Eldon Nelson Home Institution: University of Minnesota Twin Cities Campus Faculty Mentor: Professor Larry Kinney Project: Designing a DMA Controller for the Motorola 68HC12 Microcontroller DMA (direct memory access) is a technology used in modern computers to efficiently transfer data to and from external memory. This project incorporates the idea of DMA to the Motorola 68HC12 microcontroller; extending the abilities of this piece of hardware to accomplish tasks that would be otherwise impossible. Since the 68HC12 does not have bus mastering capabilities, innovative techniques were used to build an external memory bus outside of the microcontroller.
	Participant: Seth Thomas Sweep Home institution: University of Minnesota Morris Faculty Mentor: Kia Bazargan Project: JBits and Java as an Interface for Field Programmable Gate Arrays In this project, our team studied JBits--an extension of the Java programming language that allows us to develop applications that utilize the processing power of Field Programmable Gate Arrays (FPGAs). With these hardware devices, we can implement digital logic to create almost any type of basic circuit needed to fit a particular computational task. On the fly, these digital circuits can be adjusted or redesigned to allow for more task-specific computation. This power is known as reconfigurable computing. JBits allows us a means to design and debug FPGAs applications entirely in Java code. For the final part of this project, we are using JBits to create software that eventually will allow us to run speed tests to compare the time of computation between CPUs and FPGAs.