Mass Absorption Coefficient of Tungsten and Tantalum, 1450 eV to 2350 eV: Experiment, Theory, and Application

Published

January 1, 2003

Author(s)

Zachary H. Levine, S Grantham, Charles S. Tarrio, D Paterson, I McNulty, T M. Levin, A L. Ankudinov, J J. Rehr

Abstract

The mass absorption coefficient of tungsten and tantalum was measured with soft x-ray photons from 1450 eV to 2350 eV using an undulator source. This includes the M₃, M₄, and M₅ absorption edges. X-ray absorption fine structure was calculated within a real-space multiple scattering formalism; the predicted structure was observed for tungsten and to a lesser degree tantalum as well.Separately, the effects of dynamic screening were observed as shown by an atomic calculation within the relativistic time-dependent local-density approximation.Dynamic screening effects influence the spectra at the 25 % level and are observed for both tungsten and tantalum. We applied these results to characterize spatially-resolved spectra of a tungsten integrated circuit interconnect obtained using a scanning transmission x-ray microscope. The results indicate tungsten fiducial markers were deposited into silica trenches with a depths of 50% and 60% of the markers' heights.

Citation

Journal of Research (NIST JRES) -

Volume

108 No. 1

NIST Pub Series

Journal of Research (NIST JRES)

Pub Type

NIST Pubs

Keywords

integrated circuit interconnect, M-sub-3 edge, M-sub-4 edge, M-sub-5 edge, mass absorption, microspectroscopy, tantalum, transmission, tungsten

Citation

Levine, Z. , Grantham, S. , Tarrio, C. , Paterson, D. , McNulty, I. , Levin, T. , Ankudinov, A. and Rehr, J. (2003), Mass Absorption Coefficient of Tungsten and Tantalum, 1450 eV to 2350 eV: Experiment, Theory, and Application, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed October 10, 2025)