skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Atomic structure considerations for the low-temperature opacity of Sn

Abstract

Here, we have begun a preliminary investigation into the opacity of Sn at low temperatures (< 50 eV). The emissivity and opacity of Sn is a crucial factor in determining the utility of Sn in EUV lithography, with numerous industrial implications. To this end, we have been exploring the accuracy of some approximations used in opacity models for the relevant ion stages of Sn (neutral through ~ 18 times ionized). We also find that the use of intermediate-coupling, as compared to full configuration-interaction, is not adequate to obtain accurate line positions of the important bound-bound transitions in Sn. One requires full configuration-interaction to properly describe the strong mixing between the various n=4 sub-shells that give rise to the Δn= 0 transitions that dominate the opacity spectrum at low temperatures. Furthermore, since calculations that include full configuration-interaction for large numbers of configurations quickly become computationally prohibitive, we have explored hybrid calculations, in which full configuration-interaction is retained for the most important transitions, while intermediate-coupling is employed for all other transitions. After extensive exploration of the atomic structure properties, local-thermodynamic-equilibrium (LTE) opacities are generated using the ATOMIC code at selected temperatures and densities and compared to experiment.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kansas State Univ., Manhattan, KS (United States). J.R. Macdonald Lab.
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1352383
Alternate Identifier(s):
OSTI ID: 1419534
Report Number(s):
LA-UR-17-21866
Journal ID: ISSN 1574-1818; TRN: US1700562
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
High Energy Density Physics
Additional Journal Information:
Journal Volume: 23; Journal Issue: C; Journal ID: ISSN 1574-1818
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; opacity

Citation Formats

Colgan, J., Kilcrease, D. P., Abdallah, J., Sherrill, M. E., Fontes, C. J., Hakel, P., and Armstrong, G. S. J. Atomic structure considerations for the low-temperature opacity of Sn. United States: N. p., 2017. Web. doi:10.1016/j.hedp.2017.03.009.
Colgan, J., Kilcrease, D. P., Abdallah, J., Sherrill, M. E., Fontes, C. J., Hakel, P., & Armstrong, G. S. J. Atomic structure considerations for the low-temperature opacity of Sn. United States. doi:10.1016/j.hedp.2017.03.009.
Colgan, J., Kilcrease, D. P., Abdallah, J., Sherrill, M. E., Fontes, C. J., Hakel, P., and Armstrong, G. S. J. Fri . "Atomic structure considerations for the low-temperature opacity of Sn". United States. doi:10.1016/j.hedp.2017.03.009. https://www.osti.gov/servlets/purl/1352383.
@article{osti_1352383,
title = {Atomic structure considerations for the low-temperature opacity of Sn},
author = {Colgan, J. and Kilcrease, D. P. and Abdallah, J. and Sherrill, M. E. and Fontes, C. J. and Hakel, P. and Armstrong, G. S. J.},
abstractNote = {Here, we have begun a preliminary investigation into the opacity of Sn at low temperatures (< 50 eV). The emissivity and opacity of Sn is a crucial factor in determining the utility of Sn in EUV lithography, with numerous industrial implications. To this end, we have been exploring the accuracy of some approximations used in opacity models for the relevant ion stages of Sn (neutral through ~ 18 times ionized). We also find that the use of intermediate-coupling, as compared to full configuration-interaction, is not adequate to obtain accurate line positions of the important bound-bound transitions in Sn. One requires full configuration-interaction to properly describe the strong mixing between the various n=4 sub-shells that give rise to the Δn= 0 transitions that dominate the opacity spectrum at low temperatures. Furthermore, since calculations that include full configuration-interaction for large numbers of configurations quickly become computationally prohibitive, we have explored hybrid calculations, in which full configuration-interaction is retained for the most important transitions, while intermediate-coupling is employed for all other transitions. After extensive exploration of the atomic structure properties, local-thermodynamic-equilibrium (LTE) opacities are generated using the ATOMIC code at selected temperatures and densities and compared to experiment.},
doi = {10.1016/j.hedp.2017.03.009},
journal = {High Energy Density Physics},
number = C,
volume = 23,
place = {United States},
year = {Fri Mar 31 00:00:00 EDT 2017},
month = {Fri Mar 31 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Save / Share:
  • Current research on sources for extreme ultraviolet lithography (EUVL) has converged on the use of discharge or laser produced plasmas containing xenon, tin, or lithium with tin showing by far the most promise. Because of their density, radiation transport from these plasmas is a major issue and accurate photoabsorption cross sections are required for the development of the plasma models needed to optimize conditions for source operation. The relative EUV photoionization cross sections of Sn I through Sn IV have been measured and from a comparison with the results of many body calculations, the cross section has been estimated tomore » be close to 11 Mb in each species at 13.5 nm (91.8 eV), the wavelength of choice for EUVL.« less
  • A series of Y{sub 2-{delta}}Bi{sub {delta}}Sn{sub 2}O{sub 7} ({delta}=0, 0.1, 0.3, 0.5, 1.0, 1.5, and 2.0) nanocrystals were successfully synthesized by the low-temperature hydrothermal method. The structures of serial compounds were characterized by X-ray diffraction (XRD) and infrared (IR) absorption spectroscopy, and were further refined by TOPAS software by Bruker AXS using the whole powder pattern data. These materials form a series of cubic pyrochlore-type oxides at low temperature and are consistent with Vegards' law, indicating that the hydrothermal synthesis conferred a higher chemical homogeneity and reactivity on the powders, and resulting in low crystallization temperature for the pyrochlore-phase complexmore » oxides.« less
  • The crystal structure of beta-BaZr(PO{sub 4}){sub 2}, archetype of the high-temperature forms of BaM(PO{sub 4}){sub 2} phosphates (with M=Ti, Zr, Hf and Sn), has been solved ab initio by Rietveld analysis from synchrotron X-ray powder diffraction data. The phase transition appears as a topotactic modification of the monoclinic (S.G. C2/m) lamellar alpha-structure into a trigonal one (S.G. P3-barm1) through a simple mechanism involving the unfolding of the [Zr(PO{sub 4}){sub 2}]{sub n}{sup 2-} layers. The thermal expansion is very anisotropic (e.g., -4.1<alpha{sub i}<34.0x10{sup -6} K{sup -1} in the case of alpha-BaZr(PO{sub 4}){sub 2}) and quite different in the two forms, asmore » a consequence of symmetry. It stems from a complex combination of several mechanisms, involving bridging oxygen rocking in M-O-P linkages, and 'bond thermal expansion'. - Graphical abstract: The layered high-temperature form of BaM(PO{sub 4}){sub 2}, only expands along the c-axis.« less
  • In this letter, we study the structural and magnetic properties of Ge{sub 1-x-y}Sn{sub x}Mn{sub y} films grown on Ge(001) by low temperature molecular beam epitaxy using X-ray diffraction, high resolution transmission electron microscopy, and superconducting quantum interference device. Like in Mn doped Ge films, Mn atoms diffuse during the growth and aggregate into vertically aligned Mn-rich nanocolumns of a few nanometers in diameter. Transmission electron microscopy observations in plane view clearly indicate that the Sn incorporation is not uniform with concentration in Mn rich vertical nanocolumns lower than the detection limit of electron energy loss spectroscopy. The matrix exhibits amore » GeSn solid solution while there is a Sn-rich GeSn shell around GeMn nanocolumns. The magnetization in Ge{sub 1-x-y}Sn{sub x}Mn{sub y} layers is higher than in Ge{sub 1-x}Mn{sub x} films. This magnetic moment enhancement in Ge{sub 1-x-y}Sn{sub x}Mn{sub y} is probably related to the modification of the electronic structure of Mn atoms in the nanocolumns by the Sn-rich shell, which is formed around the nanocolumns.« less