Depth dependence for extended x-ray-absorption fine-structure spectroscopy detected via electron yield in He and in vacuum

Journal Article · Fri Jul 01 00:00:00 EDT 1988 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.38.26· OSTI ID:7203889

Elam, W T; Kirkland, J P; Neiser, R A; Wolf, P D

X-ray absorption spectra have been measured using electron detection with both vacuum and helium gas surrounding the samples. The samples consisted of thin iron films covered with various thicknesses of aluminum to determine the contribution versus depth. The height of the iron K--absorption-edge jump decreases exponentially with aluminum covering thickness, with a 1/e depth of 1600 A. The addition of helium gas forms an ionization detector for the electrons, which have an average energy of about 2500 eV. The effects of electrode geometry and bias voltage are evaluated. When operated in a linear-response region, the signal-to-noise ratio for this method is excellent and the extended x-ray-absorption fine-structure (EXAFS) amplitudes agree with transmission measurements to better than 3%.

• Research Organization: Condensed Matter Physics Branch, Condensed Matter and Radiation Science Division, Naval Research Laboratory, Washington, D.C. 20375-5000
• OSTI ID: 7203889
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 38:1
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM
ABSORPTION SPECTRA
X-RAY SPECTRA
IRON
ELECTRONS
FILMS
FINE STRUCTURE
GASES
HELIUM
HIGH VACUUM
IONIZATION
LAYERS
SYNCHROTRON RADIATION
BREMSSTRAHLUNG
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ELEMENTS
FERMIONS
FLUIDS
LEPTONS
METALS
NONMETALS
RADIATIONS
RARE GASES
SPECTRA
TRANSITION ELEMENTS
360104* - Metals & Alloys- Physical Properties