Pomona College’s Seaver South Laboratory now holds a new field-emission scanning electron microscope (FE-SEM), funded by a $546,273 grant from the National Science Foundation (NSF) to Harvey Mudd College and Pomona.
Pomona physics professor David Tanenbaum led professors from HMC (Nancy Lape and Elizabeth Orwin of the engineering department and Hal Van Ryswyk of the chemistry department) and Pomona (Robert Gaines and Jade Star Lackey of the geology department and Charles Taylor of the chemistry department) in writing the grant for the new FE-SEM.
The FE-SEM, which will eventually move to the remodeled Millikan Laboratory, serves to replace the old FE-SEM purchased in 2004.
“We had an electron microscope before, but it was really on the verge of failure,” Tanenbaum said. “The system we had worked, but it wasn’t going to last much longer.”
According to Tanenbaum, the new FE-SEM functions at higher resolution and has a wider range of detection options than the old one. These new detection options include multiple secondary electron detectors, an optical photon detector, and an X-ray detector.
“We did, in the process of getting something new, get something that had new features that were better and allowed us to do new things that we couldn’t have done before,” Tanenbaum said.
Records regarding usage of the old FE-SEM demonstrated to the NSF that such a tool would continue to be valuable to the Claremont community and that researchers understood how to use it effectively, Tanenbaum said.
“The microscope’s about the whole city of Claremont having a first-rate research instrument,” Tanenbaum said.
Although the majority of usage comes from HMC- and Pomona-affiliated researchers, any member of the Claremont community is free to use the FE-SEM, provided that his or her research project is approved by a college-associated faculty member and that he or she participates in a training session. Already, there are researchers from the Rancho Santa Ana Botanical Garden coming to use the FE-SEM.
At many institutions, users must pay a fee that goes to fund a service contract for the instrument. However, part of the proposal for HMC and Pomona’s FE-SEM involved the NSF funding the first three years of service. HMC and Pomona have agreed to split the cost of the service contract for the four years following the three that are funded, according to Tanenbaum.
In exchange for use of the instrument, researchers must turn in written reports and pictures of results obtained from the FE-SEM not only to ensure student learning and proper use of the equipment, but also to maintain a usage record.
“Although I have fun using this tool, it’s really not for me to use,” Tanenbaum said. “It’s really for the undergraduates to learn to use. We’re training lots and lots of undergraduates, and they’re going to be the ones to use the instrument.”
Tanenbaum’s research involves creating novel forms of carbon, so his lab uses the FE-SEM as a processing inspection tool. Also, he uses it as a way to investigate the size and uniformity of plastic solar cells created by his lab.
Geology major Laura Haynes PO ’13 uses the FE-SEM to determine the composition of calcium-carbonate sediment samples.
“I think it’s good to get exposure to a technique that’s pretty widely used in many scientific fields, and I think it’s really good research experience,” Haynes said. “It’s nice to be able to come out of Pomona and say that I have experience with this machine and that I really understand how it works and what its capabilities are.”
Lackey’s research involves dating crystals from minerals up to 1.7 billion years old. The new FE-SEM allows Lackey to map subtle properties on the crystals and date them accordingly.
“Without the new SEM, we’d be blind to these delicate features and probably produce analyses that were mixtures of the different age domains, a meaningless result,” Lackey wrote in an e-mail to TSL.
The FE-SEM is not only changing the way certain labs can do research but also the way in which departments can come together.
“[The new FE-SEM] is very exciting for two reasons,” Tanenbaum said. “One is because it enables us to do great science. The second is because it’s a joint effort between Pomona faculty and Harvey Mudd faculty. It’s really built bridges between the schools and between departments.”