
June 2001 From Lehigh University Probing the infinitesimal, Microscopy School at Lehigh U. is a big dealHow tiny is tiny - and how important is it to know? Well, the tiniest of material behaviors can sink the grandest of mortal dreams. The Titanic, metallurgists now speculate, may have been doomed while it was being built, when a handful of sulfur atoms slipped unseen into the grains of iron in the ship's hull, rendering it brittle. Consider a more mundane example. A layer of copper atoms inserted between the aluminum crystals in an integrated circuit can increase the lifetime of the wires in the circuit by 50 times. The nearly-invisible world comes into focus every June at Lehigh University's two-week Microscopy School. The 30-year-old school, largest of its kind, draws up to 200 students, mostly professional engineers and scientists. Cameca, Hitachi, Digital Instruments and a dozen other companies bring the latest microscopes, assembling the largest array of new instruments anywhere. This year's school, which runs June 10-22, features two events geared towards artists and online enthusiasts: � A slide show by David Scharf, a California photographer whose photo-micrographs have been published in Life, National Geographic and Scientific American. Inventor of the Wideband Multi-Detector Color Synthesizer, Scharf uses scanning electron microscopy to expose "A Marine Mite Feeding on a Mystacocarid," "Eye of a Fly," "Polygonum Pollen Grain" and dozens of other images. � A "remote microscopy" lab in which microscopists at Lehigh will operate an electron microscope at the University of Michigan via the Internet. Lehigh undergraduate students have conducted remote labs several times, using a Macintosh computer to control the electron microscope at Oak Ridge National Laboratory in Tennessee. Modern technology enables scientists in one place to adjust magnification and other settings and even control the movement and position of a specimen under a microscope at another location. Electron microscopy has helped engineers change the way the world lives and communicates, says David Williams, professor of materials science and engineering at Lehigh and school co-organizer. The silicon chips in faxes, cell phones and VCRs owe their existence to an improved understanding of how materials behave, often at the microscopic level. So do ballerinas who dance on artificial hips and legless men who jog on artificial limbs. "Much of the semiconductor industry has depended on scanning electron microscopy (SEM)," says Williams. "SEMs on the production line at places like Intel detect defects in semiconductor chips. The lines etched in a chip push the limit of the resolution of an SEM, which is about 800 angstroms in width." Airfares that have remained constant for the past 25 years are a testament, Williams says, to increased efficiency of jet engines and improved design of fuselage and wings. These in turn have resulted from a better understanding of aluminum- and nickel-based alloys gained with the help of electron microscopy. "Electron microscopy helps us understand the microstructure and microchemistry of materials," says Williams. "Once we know those things, then we can learn how to control the physical, mechanical, electronic and chemical properties of a material." Using scanning tunnelling microscopes, it is now possible to manipulate individual atoms, create new materials and give new properties to old ones. The emerging field of nanotechnology is using electron microscopy to make smaller and smaller electric motors and other "microsystems" and place them on a microchip. One day, engineers hope to make miniature robots small enough to travel along blood vessels and carry out minute repairs. Lehigh's Microscopy School offers classes in all types of modern electron microscopy, including SEM, X-ray microanalysis, analytical electron microscopy, scanning tunneling spectroscopy and microscopy, and atomic force microscopy. Scharf is scheduled to give his slide show at a banquet beginning at 6:30 p.m. on Wednesday, June 13. He will also teach a lab on SEM photography on Thursday, June 14, at four times: 1:15 p.m., 4 p.m., 7:15 p.m. and 8:30 p.m. The remote microscopy lab will be conducted by John Mansfield, associate research scientist at the University of Michigan, on Friday, June 15, at three times: 8:30 a.m., 9:45 a.m. and 11 a.m.
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