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Assessing out-of-band flare effects at the wafer level for EUV lithography (open access)

Assessing out-of-band flare effects at the wafer level for EUV lithography

To accurately estimate the flare contribution from the out-of-band (OOB), the integration of a DUV source into the SEMATECH Berkeley 0.3-NA Micro-field Exposure tool is proposed, enabling precisely controlled exposures along with the EUV patterning of resists in vacuum. First measurements evaluating the impact of bandwidth selected exposures with a table-top set-up and subsequent EUV patterning show significant impact on line-edge roughness and process performance. We outline a simulation-based method for computing the effective flare from resist sensitive wavelengths as a function of mask pattern types and sizes. This simulation method is benchmarked against measured OOB flare measurements and the results obtained are in agreement.
Date: January 25, 2010
Creator: George, Simi; Naulleau, Patrick; Kemp, Charles; Denham, Paul & Rekawa, Senajith
System: The UNT Digital Library
A Case for Including Transactions in OpenMP (open access)

A Case for Including Transactions in OpenMP

Transactional Memory (TM) has received significant attention recently as a mechanism to reduce the complexity of shared memory programming. We explore the potential of TM to improve OpenMP applications. We combine a software TM (STM) system to support transactions with an OpenMP implementation to start thread teams and provide task and loop-level parallelization. We apply this system to two application scenarios that reflect realistic TM use cases. Our results with this system demonstrate that even with the relatively high overheads of STM, transactions can outperform OpenMP critical sections by 10%. Overall, our study demonstrates that extending OpenMP to include transactions would ease programming effort while allowing improved performance.
Date: January 25, 2010
Creator: Wong, M.; Bihari, B. L.; de Supinski, B. R.; Wu, P.; Michael, M.; Liu, Y. et al.
System: The UNT Digital Library
Development of Abraham model correlations for solvation characteristics of secondary and branched alcohols (open access)

Development of Abraham model correlations for solvation characteristics of secondary and branched alcohols

This article discusses the development of Abraham model correlations for solvation characteristics of secondary and branched alcohols.
Date: January 25, 2010
Creator: Sprunger, Laura M.; Achi, Sai S.; Pointer, Racheal; Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
System: The UNT Digital Library
Development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients (open access)

Development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients

This article discusses the development of correlations for describing solute transfer into acyclic alcohol solvents based on the Abraham model and fragment-specific equation coefficients.
Date: January 25, 2010
Creator: Sprunger, Laura M.; Achi, Sai S.; Abraham, M. H. (Michael H.) & Acree, William E. (William Eugene)
System: The UNT Digital Library
Equations for the Transfer of Neutral Molecules and Ionic Species from Water to Organic phases (open access)

Equations for the Transfer of Neutral Molecules and Ionic Species from Water to Organic phases

Article on equations for the transfer of neutral molecules and ionic species from water to organic phases.
Date: January 25, 2010
Creator: Abraham, M. H. (Michael H.) & Acree, William E. (William Eugene)
System: The UNT Digital Library
High Amplitude (delta)-Scutis in the Large Magellanic Cloud (open access)

High Amplitude (delta)-Scutis in the Large Magellanic Cloud

The authors present 2323 High-Amplitude {delta}-Scutis (HADS) candidates discovered in the Large Magellanic Cloud (LMC) by the SuperMACHO survey (Rest et al. 2005). Frequency analyses of these candidates reveal that several are multimode pulsators, including 119 whose largest amplitude of pulsation is in the fundamental (F) mode and 19 whose largest amplitude of pulsation is in the first overtone (FO) mode. Using Fourier decomposition of the HADS light curves, they find that the period-luminosity (PL) relation defined by the FO pulsators does not show a clear separation from the PL-relation defined by the F pulsators. This differs from other instability strip pulsators such as type c RR Lyrae. They also present evidence for a larger amplitude, subluminous population of HADS similar to that observed in Fornax (Poretti et al. 2008).
Date: January 25, 2010
Creator: Garg, A.; Cook, K. H.; Nikolaev, S.; Huber, M. E.; Rest, A.; Becker, A. C. et al.
System: The UNT Digital Library
Lithium Coatings on NSTX Plasma Facing Components and Its Effects On Boundary Control, Core Plasma Performance, and Operation (open access)

Lithium Coatings on NSTX Plasma Facing Components and Its Effects On Boundary Control, Core Plasma Performance, and Operation

NSTX high-power divertor plasma experiments have used in succession lithium pellet injection (LPI), evaporated lithium, and injected lithium powder to apply lithium coatings to graphite plasma facing components. In 2005, following wall conditioning and LPI, discharges exhibited edge density reduction and performance improvements. Since 2006, first one, and now two lithium evaporators have been used routinely to evaporate lithium onto the lower divertor region at total rates of 10-70 mg/min for periods 5-10 min between discharges. Prior to each discharge, the evaporators are withdrawn behind shutters. Significant improvements in the performance of NBI heated divertor discharges resulting from these lithium depositions were observed. These evaporators are now used for more than 80% of NSTX discharges. Initial work with injecting fine lithium powder into the edge of NBI heated deuterium discharges yielded comparable changes in performance. Several operational issues encountered with lithium wall conditions, and the special procedures needed for vessel entry are discussed. The next step in this work is installation of a Liquid Lithium Divertor surface on the outer part of the lower divertor.
Date: January 25, 2010
Creator: H.W.Kugel, M.G.Bell, H.Schneider, J.P.Allain, R.E.Bell, R Kaita, J.Kallman, S. Kaye, B.P. LeBlanc, D. Mansfield, R.E. Nygen, R. Maingi, J. Menard, D. Mueller, M. Ono, S. Paul, S.Gerhardt, R.Raman, S.Sabbagh, C.H.Skinner, V.Soukhanovskii, J.Timberlake, L.E.Zakharov, and the NSTX Research Team
System: The UNT Digital Library
A ROSE-based OpenMP 3.0 Research Compiler Supporting Multiple Runtime Libraries (open access)

A ROSE-based OpenMP 3.0 Research Compiler Supporting Multiple Runtime Libraries

OpenMP is a popular and evolving programming model for shared-memory platforms. It relies on compilers for optimal performance and to target modern hardware architectures. A variety of extensible and robust research compilers are key to OpenMP's sustainable success in the future. In this paper, we present our efforts to build an OpenMP 3.0 research compiler for C, C++, and Fortran; using the ROSE source-to-source compiler framework. Our goal is to support OpenMP research for ourselves and others. We have extended ROSE's internal representation to handle all of the OpenMP 3.0 constructs and facilitate their manipulation. Since OpenMP research is often complicated by the tight coupling of the compiler translations and the runtime system, we present a set of rules to define a common OpenMP runtime library (XOMP) on top of multiple runtime libraries. These rules additionally define how to build a set of translations targeting XOMP. Our work demonstrates how to reuse OpenMP translations across different runtime libraries. This work simplifies OpenMP research by decoupling the problematic dependence between the compiler translations and the runtime libraries. We present an evaluation of our work by demonstrating an analysis tool for OpenMP correctness. We also show how XOMP can be defined using …
Date: January 25, 2010
Creator: Liao, C.; Quinlan, D. & Panas, T.
System: The UNT Digital Library
UPWARD MOVEMENT OF PLUTONIUM TO SURFACE SEDIMENTS DURING AN 11-YEAR FIELD STUDY (open access)

UPWARD MOVEMENT OF PLUTONIUM TO SURFACE SEDIMENTS DURING AN 11-YEAR FIELD STUDY

An 11-y lysimeter study was established to monitor the movement of Pu through vadose zone sediments. Sediment Pu concentrations as a function of depth indicated that some Pu moved upward from the buried source material. Subsequent numerical modeling suggested that the upward movement was largely the result of invading grasses taking up the Pu and translocating it upward. The objective of this study was to determine if the Pu of surface sediments originated from atmosphere fallout or from the buried lysimeter source material (weapons-grade Pu), providing additional evidence that plants were involved in the upward migration of Pu. The {sup 240}Pu/{sup 239}Pu and {sup 242}Pu/{sup 239}Pu atomic fraction ratios of the lysimeter surface sediments, as determined by Thermal Ionization Mass Spectroscopy (TIMS), were 0.063 and 0.00045, respectively; consistent with the signatures of the weapons-grade Pu. Our numerical simulations indicate that because plants create a large water flux, small concentrations over multiple years may result in a measurable accumulation of Pu on the ground surface. These results may have implications on the conceptual model for calculating risk associated with long-term stewardship and monitored natural attenuation management of Pu contaminated subsurface and surface sediments.
Date: January 25, 2010
Creator: Kaplan, D.; Beals, D.; Cadieux, J. & Halverson, J.
System: The UNT Digital Library
Uranium Resonance Ionization Mass Spectrometry in Natural U-silicate (open access)

Uranium Resonance Ionization Mass Spectrometry in Natural U-silicate

None
Date: January 25, 2010
Creator: Knight, K B; Savina, M R; Isselhardt, B H; Hutcheon, I D; Prussin, S G & Pellin, M J
System: The UNT Digital Library