Pomona College to Demonstrate New Field Emission Scanning Electron Microscope at Open House
Pomona College will hold an open house to demonstrate their new field emission scanning electron microscope, on Thursday, May 13, from 4-6 p.m. The event will be held in room B12 of the College’s Millikan Laboratory Building (610 North College Avenue, Claremont) and is open to the public.
“The new field emission scanning electron microscope (FE-SEM) is the same type of equipment used in state of the art research labs across the country," says David Tanenbaum, a professor of physics at Pomona, and the person who spearheaded the effort to bring the new microscope to campus. “Being able to use this equipment in their research will better prepare students for graduate school as well as careers in applied sciences, such as working for technology companies.”
The FE-SEM can be used to view objects significantly smaller than those that can be seen with the college’s optical microscopes, and it can more rapidly change between magnifications, going from 20 power magnification to 200,000 power magnification, in about ten seconds.
Optical microscopes use glass lenses that bend visible light in order to magnify images but cannot be used to view objects smaller that the wavelength of light. The lowest wavelengths of visible light are somewhat less than half a micron. (One micron equals 1/1000 millimeter). The FE-SEM uses magnetic fields that guide electrons, which have much smaller wavelengths than photons in visible light and therefore can magnify smaller objects.
“One of the major motivating factors to get this equipment,” says Tanenbaum, “was student accessibility. It’s fairly difficult and expensive for students to become proficient with this equipment when using equipment off-campus and charged for access, which can be as high as $200 per hour. It takes two hours to learn the basics of using the FE-SEM and another 20 hours to become proficient. So, the costs get very high very quickly.”
Specific research projects planned for the new equipment include: fabrication and characterization of nanomechanical structures for high-sensitivity sensors, in-plane patterning and chirality control of carbon nanotubes for nanotube based electronics, novel low-cost nanofabrication process development, micro/nano-fluidic research for advancing biochip technologies, and selective gas microsensor development in collaboration with national laboratories. A key feature of these projects, says Tanenbaum, is that undergraduate students will be involved in the research.
One of Tanenbaum’s summer projects will involve carbon nanotubes, which are thought to be leading candidate for making the next era of faster electronics. The main hurdle to developing the technology is that the tubes do not naturally grow in an organized, usable order. Tanenbaum will use the new microscope in his attempts to control the location and direction of growth of carbon nanotubes.
The Pomona College departments of biology, chemistry, geology and physics, as well as the Keck Graduate Institute, all contributed to the purchase of the FE-SEM, which arrived on campus in April. It is valued at $250,000 and was purchased from Princeton University.
Pomona College, one of the nation's premier liberal arts colleges, offers a comprehensive program in the arts, humanities, social sciences, and natural sciences. Founded in 1887, the college’s hallmarks include small classes, close relationships between students and faculty, and a range of opportunities for student research.