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Focused Ion Beam Induced Effects on MOS Transistor Parameters

Description: We report on recent studies of the effects of 50 keV focused ion beam (FIB) exposure on MOS transistors. We demonstrate that the changes in value of transistor parameters (such as threshold voltage, V{sub t}) are essentially the same for exposure to a Ga+ ion beam at 30 and 50 keV under the same exposure conditions. We characterize the effects of FIB exposure on test transistors fabricated in both 0.5 {micro}m and 0.225 {micro}m technologies from two different vendors. We report on the effectiv… more
Date: July 28, 1999
Creator: Abramo, Marsha T.; Antoniou, Nicholas; Campbell, Ann N.; Fleetwood, Daniel M.; Hembree, Charles E.; Jessing, Jeffrey R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Subsurface Flow and Contaminant Transport Documentation and User's Guide

Description: This report documents a finite element code designed to model subsurface flow and contaminant transport, named FACT. FACT is a transient three-dimensional, finite element code designed to simulate isothermal groundwater flow, moisture movement, and solute transport in variably saturated and fully saturated subsurface porous media. The code is designed specifically to handle complex multi-layer and/or heterogeneous aquifer systems in an efficient manner and accommodates a wide range of boundary … more
Date: July 28, 1999
Creator: Aleman, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sanitary Landfill Supplemental Test Final Report

Description: This report summarizes the performance of the Sanitary Landfill Supplemental Test data, an evaluation of applicability, conclusions, recommendations, and related information for implementation of this remediation technology at the SRS Sanitary Landfill.
Date: July 28, 1999
Creator: Altman, D. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Die Backside FIB Preparation for Identification and Characterization of Metal Voids

Description: Both the increased complexity of integrated circuits, resulting in six or more levels of integration, and the increasing use of flip-chip packaging have driven the development of integrated circuit (IC) failure analysis tools that can be applied to the backside of the chip. Among these new approaches are focused ion beam (FIB) tools and processes for performing chip edits/repairs from the die backside. This paper describes the use of backside FIB for a failure analysis application rather than f… more
Date: July 28, 1999
Creator: Antoniou, Nicholas; Campbell, Ann N. & Filter, William F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Laser damage of dichroic coatings in a high average power laser vacuum resonator

Description: In our application, dichroics in a high average power, near-infrared, laser system have short operating lifetimes. These dichroics were used as the resonator fold mirrors and permitted the transmission of the pumping argon (Ar) ion laser light. Representative samples of two different dichroic optics were taken off-line and the transmission performance monitored in various scenarios. Irradiating these optics under resonator vacuum conditions, ({le}1 mT, 11.7 kW/cm{sup 2}, Ar laser running all wa… more
Date: July 28, 1999
Creator: Arnold, P. A.; Berzins, L. V.; Chow, R. & Erbert, G. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Research Opportunities in Crystalline Silicon Photovoltaics for the 21st Century

Description: Crystalline silicon continues to be the dominant semiconductor material used for terrestrial photovoltaics. This paper discusses the scientific issues associated with silicon photovoltaics processing, and cell design that may yield cell and module performance improvements that are both evolutionary and revolutionary in nature. We first survey critical issues in ''thick'' crystalline silicon photovoltaics, including novel separations processes for impurity removal, impurity and defect fundamenta… more
Date: July 28, 1999
Creator: Atwater, Harry A.; Ciszek, Ted; Feldman, Leonard C.; Gee, James; Rohatgi, Ajeet & Sopori, Bhushan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

3D finite-difference frequency-domain code for electromagnetic induction tomography

Description: The effect of shrapnel on target chamber components and experiments at large lasers such as the National Ignition Facility at LLNL and the Megajoule Laser at CESTA in France is an important issue in fielding targets and exposure samples. Modeling calculations are likely to be an important component of this effort. Some work in this area has been performed by French workers, who are collaborating with the LLNL on many issues relating to target chamber, experiment-component, and diagnostics survi… more
Date: July 28, 1999
Creator: Berryman, J. G.; Champagne, N. J., II & Buettner, H. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Ingestion Pathway Transfer Factors for Plutonium and Americium

Description: Overall transfer factors for major ingestion pathways are derived for plutonium and americium. These transfer factors relate the radionuclide concentration in a given foodstuff to deposition on the soil. Equations describing basic relationships consistent with Regulatory Guide 1.109 are followed. Updated values and coefficients from IAEA Technical Reports Series No. 364 are used when a available. Preference is given to using factors specific to the Savannah River Site.
Date: July 28, 1999
Creator: Blanchard, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A New Bound for the Ration Between the 2-Matching Problem and Its Linear Programming Relaxation

Description: Consider the 2-matching problem defined on the complete graph, with edge costs which satisfy the triangle inequality. We prove that the value of a minimum cost 2-matching is bounded above by 4/3 times the value of its linear programming relaxation, the fractional 2-matching problem. This lends credibility to a long-standing conjecture that the optimal value for the traveling salesman problem is bounded above by 4/3 times the value of its linear programming relaxation, the subtour elimination pr… more
Date: July 28, 1999
Creator: Boyd, Sylvia & Carr, Robert
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Modeling a Dry Etch Process for Large-Area Devices

Description: There has been considerable interest in developing dry processes which can effectively replace wet processing in the manufacture of large area photovoltaic devices. Environmental and health issues are a driver for this activity because wet processes generally increase worker exposure to toxic and hazardous chemicals and generate large volumes of liquid hazardous waste. Our work has been directed toward improving the performance of screen-printed solar cells while using plasma processing to redu… more
Date: July 28, 1999
Creator: Buss, R.J.; Hebner, G.A.; Ruby, D.S. & Yang, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

On the Red-Blue Set Cover Problem

Description: Both the increased complexity of integrated circuits, resulting in six or more levels of integration, and the increasing use of flip-chip packaging have driven the development of integrated circuit (IC) failure analysis tools that can be applied to the backside of the chip. Among these new approaches are focused ion beam (FIB) tools and processes for performing chip edits/repairs from the die backside. This paper describes the use of backside FIB for a failure analysis application rather than f… more
Date: July 28, 1999
Creator: Carr, Robert D.; Doddi, Srinivas; Konjevod, Goran & Marathe, Madhav
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Strengthening Integrality Gaps for Capacitated Network Design and Covering Problems

Description: A capacitated covering IP is an integer program of the form min{l_brace}ex{vert_bar}Ux {ge} d, 0 {le} x {le} b, x {element_of} Z{sup +}{r_brace}, where all entries of c, U, and d are nonnegative. Given such a formulation, the ratio between the optimal integer solution and the optimal solution to the linear program relaxation can be as bad as {parallel}d{parallel}{sub {proportional_to}}, even when U consists of a single row. They show that by adding additional inequalities, this ratio can be imp… more
Date: July 28, 1999
Creator: Carr, Robert D.; Fleischer, Lisa K.; Leung, Vitus J. & Phillips, Cynthia A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Consequence analysis of IWTS metal water reactions (Fauske and Associates report 99-35)

Description: The report describes the consequences of postulated thermally unstable conditions in the IWTS knock out pot. The consequence analysis shows that both the knock out pot and particulate bed will stay intact, and that releases will be minor. Reaction rate limitations prevent knock out pot pressure and/or temperature from even approaching values that would threaten structural integrity. Source term calculations based on a particle bed with a homogeneous mixture of metal and oxide particles yield a … more
Date: July 28, 1999
Creator: Duncan, D. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Actinide Biocolloid Formation in Brine by Halophilic Bacteria

Description: We examined the ability of a halophilic bacterium (WFP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell Surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited volubility.… more
Date: July 28, 1999
Creator: Gillow, J. B.; Francis, A. J.; Dodge, C. J.; Harris, R.; Beveridge, T. J.; Brady, P. V. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Probabilistic Accident Consequence Uncertainty - A Joint CEC/USNRC Study

Description: The joint USNRC/CEC consequence uncertainty study was chartered after the development of two new probabilistic accident consequence codes, MACCS in the U.S. and COSYMA in Europe. Both the USNRC and CEC had a vested interest in expanding the knowledge base of the uncertainty associated with consequence modeling, and teamed up to co-sponsor a consequence uncertainty study. The information acquired from the study was expected to provide understanding of the strengths and weaknesses of current mode… more
Date: July 28, 1999
Creator: Gregory, Julie J. & Harper, Frederick T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Two-station phase velocity determination for structure in North Africa

Description: The seismic structure of North Africa is poorly understood due to the relative paucity of stations and seismicity when compared to other continental regions of the world. A better understanding of the velocity structure in this area will allow improved models of travel times and regional phase amplitudes. Such models will improve location and identification capability in this region leading to more effective monitoring of the Comprehensive Nuclear-Test-Ban Treaty. Using regional-to-teleseismic … more
Date: July 28, 1999
Creator: Hazler, S; Pasyanos, M; Sheehan, A & Walter, W
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

River Protection Project information systems assessment

Description: The Information Systems Assessment Report documents the results from assessing the Project Hanford Management Contract (PHMC) Hanford Data Integrator 2000 (HANDI 2000) system, Business Management System (BMS) and Work Management System phases (WMS), with respect to the System Engineering Capability Assessment Model (CAM). The assessment was performed in accordance with the expectations stated in the fiscal year (FY) 1999 Performance Agreement 7.1.1, item (2) which reads, ''Provide an assessment… more
Date: July 28, 1999
Creator: JOHNSON, A.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Energia Renovable para Centros de Salud Rurales (Renewable Energy for Rural Health Clinics)

Description: Esta es la primera de una serie de guias de aplicaciones que el Programa de Energia de Villas de NREL esta comisionando para acoplar sistemas comerciales renovables con aplicaciones rurales, incluyendo agua, escuelas rurales y micro empresas. La guia esta complementada por las actividades de desarrollo del Programa de Energia de Villas de NREL, proyectos pilotos internacionales y programas de visitas profesionales.
Date: July 28, 1999
Creator: Jimenez, T. & Olson, K.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
open access

STRUCTURAL CALCULATIONS FOR THE CODISPOSAL OF TRIGA SPENT NUCLEAR FUEL IN A WASTE PACKAGE

Description: The purpose of this analysis is to determine the structural response of a TRIGA Department of Energy (DOE) spent nuclear fuel (SNF) codisposal canister placed in a 5-Defense High Level Waste (DHLW) waste package (WP) and subjected to a tipover design basis event (DBE) dynamic load; the results will be reported in terms of displacements and stress magnitudes. This activity is associated with the WP design.
Date: July 28, 1999
Creator: Mastilovic, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Photosensitive Point Defects in Optical Glasses: Science and Applications

Description: The understanding and manipulation of the point defect structure in oxide glasses have been critical to the enhanced performance and reliability of optical-fiber-based, photosensitive photonic devices that currently found widespread application in telecommunications and remote sensing technologies. We provide a brief review of past research investigating photosensitive mechanisms in germanosilicate glasses, the primary material system used in telecommunications fibers. This discussion motivates… more
Date: July 28, 1999
Creator: Potter, B.G. Jr. & Simmons-Potter, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Distributed Sensing and Shape Control of Piezoelectric Bimorph Mirrors

Description: As part of a collaborative effort between Sandia National Laboratories and the University of Kentucky to develop a deployable mirror for remote sensing applications, research in shape sensing and control algorithms that leverage the distributed nature of electron gun excitation for piezoelectric bimorph mirrors is summarized. A coarse shape sensing technique is developed that uses reflected light rays from the sample surface to provide discrete slope measurements. Estimates of surface profiles … more
Date: July 28, 1999
Creator: Redmond, James M.; Barney, Patrick S. & Henson, Tammy D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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