Thinking big by looking small
The University of North Texas is taking a big step to study the smallest pieces of matter in the world.
The university has upgraded its LEAP3000 atom probe tomography microscope. The upgrade will allow students and faculty researchers to examine the structure and elemental makeup of additional types of specimens at the nanoscale, which uses the nanometer as a unit of measurement. A nanometer is one-billionth of a meter.
Dr. Oscar Garcia, founding dean of UNT's College of Engineering, which acquired the LEAP3000, says the microscope originally used an ultra-fast voltage pulse superimposed on a high electrical field to evaporate and analyze atoms. The tomography system, however, was limited to conductive samples, such as metals.
"This system has recently been upgraded to have an ultra-fast pulsed laser so that we can now analyze non-electrical conductors," he says.
The laser will allow UNT scientists to study a broader range of materials, such as semiconductors, ceramics, and glass, says Dr. Brian Gorman, director of UNT's Electron and Ion Microscopy Laboratory.
"The probe allows us to do 3D atomic scale mapping on a nanolevel," he says, adding that the upgrade will allow students to study complex systems, such as photovoltaic and fuel cells at the atomic level. Eventually, composites and organics will be added to that list, Gorman says.
Gorman adds a variety of industries are interested in the research generated by the LEAP system, including microelectronics and chemistry.
Dr. Michael Kaufman, chairman of UNT's Department of Materials Science and Engineering,
calls the ability to do atom probe tomography on non-electrical conductors "truly significant."
"Many of the speculations about the distribution of elements in complex, multi-phase nanoscale samples can now be checked for the first time. This will enable important advances to be made in many materials-limited technologies," he says.
The LEAP3000 is housed at UNT's Research Park campus, which is north of the university's main campus in Denton. The microscope was purchased with a grant from Congress in the 2004 Defense Appropriations Bill. The upgrade was purchased with money from a second grant in the 2005 Defense Appropriations Bill. Congressman Michael Burgess and Senator Kay Bailey Hutchison led efforts in Washington D.C. to secure federal funds for both grants.
UNT News Service Phone Number: (940) 565-2108