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State-Of-The-Art Microscope Pushes Barrier of What's Too Small to See

*By Duncan Mansfield* Associated Press Writer
Published: Sep 21, 2004

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OAK RIDGE, Tenn. (AP) - Oak Ridge National Laboratory researchers are 
peering into the atomic world with record clarity, developing an 
electron microscope image that can distinguish the individual, 
dumbbell-shaped atoms of a silicon crystal.

"Every time you see something more clearly you learn some secrets," said 
Stephen Pennycook, who heads the lab's electron microscopy group.

In a Sept. 17 article in the journal Science, Pennycook and colleagues 
wrote that they have achieved an image resolution at 0.6 angstrom, 
breaking the previous record of 0.7 angstrom which the lab set earlier 
this year.

An angstrom, the smallest wavelength of light, is about 500,000 times 
smaller than the thickness of a human hair.

Researchers say being able to see how materials bond together at an 
atomic level could prove a significant benefit to the semiconductor 
industry, chemistry and in the development of new materials.

For its latest findings, the Oak Ridge lab used a 300-kilovolt 
state-of-the-art electron microscope aided by new computerized imaging 
technology developed by Nion Co. of Kirkland, Wash.

The technology, called aberration correction, fixes imperfections on the 
microscope's electron lenses.

"We are crossing that threshold where we can really see atoms clearly 
for the first time ever," Pennycook said.

Pennycook compared the resolution correction technology to being able to 
focus 50 lenses simultaneously.

"That is what makes it really quite a historic achievement because it 
has been attempted for the last 50 years actually, and only in the last 
few years has it really proved feasible," he said.

Five years ago the Oak Ridge lab set a world record with a resolution at 
1.3 angstrom without the aberration technology. Researchers said the 
next frontier will be seeing atoms in three dimensions.

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On the Net:

Oak Ridge National Laboratory: http://www.ornl.gov

Nion Co.: http://www.nion.com

AP-ES-09-21-04 0543EDT