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Scanning Tunneling Electron Microscopy (STEM) is a powerful technique that provides magnification of conducting surfaces to the atomic level. My recent experience as a member of a group of twenty teachers selected to work for eight summer weeks with scientists at Xerox Corporation and professors at the University of Rochester has opened new vistas for me and my high school students. We learned to use the Burleigh Instructional Scanning Tunneling Microscope (ISTM), an instrument designed for educational use by the University of Rochester, Xerox Corporation, and Burleigh Instrument Inc. While the images we can produce are not of the same quality as are often seen in the research literature, care in making a sharp, uncontaminated scanning tip and data collection in a vibration-free area, can result in pictures that are more than adequate for the introduction of "atomic eyes" to my classroom.
The ISTM is useful in the study of the effect of acids and bases on metals and the surfaces of semiconductors (some experiments are described below). Cutting the platinum-iridium tip or preparing the tungsten tip and mounting the sample are hands-on activities that give students a glimpse of the technological nanoworld. This state-of-the-art instrumentation is making it possible for students to actually view atoms in their own classroom. What is truly amazing, however, is that the ISTM can be set up and atomic resolution images obtained in about an hour.
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