New technique breaks nanometer barrier in X-ray microscopy
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ARGONNE, Ill. (Nov. 9, 2006) — A new X-ray microscopy technique that observes
molecular-scale features less than a nanometer in height has been developed
by scientists at the U.S. Department of Energy's Argonne National Laboratory
in collaboration with Xradia, Inc. By combining X-ray reflection with high-resolution
X-ray microscopy, scientists can now study interactions at the nanometer-scale,
where materials often exhibit new properties. A better understanding of interactions
at the nanoscale promises to help cure the sick, protect the environment and
make the nation more secure.
This novel technique will lead to a better understanding of interfacial reactions
at surfaces, such as ion adsorption, corrosion, and catalytic reactions. In
particular, this method extends the capability of X-ray microscopy to observe
sub-nanometer-sized interfacial features directly and in real time. This non-invasive
approach complements the more widely used scanning probe microscopies and can
image the topography of a solid surface without using probe-tips near the surface.
Argonne researchers together with Xradia, a firm specializing in X-ray optics
and X-ray microscope systems, have achieved sensitivity to sub-nanometer-sized
features by using a phenomenon known as phase contrast. This breakthrough makes
it possible to look directly at individual steps on a solid surface, borrowing
a technique used previously in electron microscopy,
"The ability to see individual nanometer-scale features is an important benchmark
for X-ray microscopy" said Argonne physicist Paul Fenter. "Understanding interfacial
reactivity is vital to many areas of science and technology, from the corrosion
of metals to the transport of contaminants in the environment."
"This technique opens up the possibility of watching these processes directly
and will provide fundamentally new opportunities for understanding them," added
Steve Wang of Xradia.
This technique is a significant advance towards understanding the reactivity
of solid-surfaces. Future studies will extend these measurements to the observation
of real-time processes of mineral surfaces in contact with water. E mploying
a novel X-ray microscope setup developed by Xradia, and measurements performed
at Argonne's Advanced Photon Source, the most brilliant X-ray source in the
Western Hemisphere, was central to the teams' success.
The research, funded by the U.S. Department of Energy's Office of Basic Energy
Sciences, was carried out by a team at Argonne's Chemistry
Division, including scientists Paul Fenter, Changyong Park, Zhan Zhang, in
collaboration with Steve Wang from Xradia. The results were recently published
in Nature
Physics (Vol. 2, pages 700-704, 2006).
Xradia, Inc. is a privately held company established in 2000 to commercialize
high-resolution X-ray microscopy systems for nondestructive inspection and nano-scale
imaging. Initially targeted at failure analysis in the semiconductor IC industry,
subsequent developments have led to a suite of commercial X-ray imaging products
that have permitted expansion into markets that include metrology in semiconductor
IC production, scientific equipment, biomedical research and nanotechnology development.
Argonne National Laboratory seeks solutions to pressing national problems in science and technology.
The nation's first national laboratory, Argonne conducts leading-edge basic
and applied scientific research in virtually every scientific discipline. Argonne
researchers work closely with researchers from hundreds of companies, universities,
and federal, state and municipal agencies to help them solve their specific
problems, advance America 's scientific leadership and prepare the nation for
a better future. With employees from more than 60 nations, Argonne is managed
by UChicago
Argonne, LLC for
the U.S.
Department of Energy's Office
of Science.
For more information, please contact Eleanor Taylor (630/252-5510 or media@anl.gov) at Argonne.
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