Nanoscience is the study and manipulation of structures at atomic and molecular scales, one to several hundreds of nanometers. (One nanometer can be imagined by cutting the diameter of a human hair into 50 parts, then cutting one of those parts a thousand times more.) Nanoscience is at the core of several federally-funded interdisciplinary research programs at Georgetown University, including nanoscale electronics, biological nanoscale reaction chambers, nanocrystals, patterning of nanoneedles for injecting living cells and biological applications of conducting polymers.
Imaging and patterning at the nanoscale can be done using an electron beam, rather than light, because the wavelength of light is too large to resolve molecular and atomic structures. Scanning electron microscopes and electron-beam lithography systems are key tools in the nanoscience revolution. Although there are currently no facilities for this type of high-resolution microscopy and patterning at Georgetown, faculty members have been very resourceful by using facilities off campus, through external collaborations. Unfortunately, off-campus facilities severely limit the research, requiring travel time that limits the opportunities of all researchers, and especially students with their tight class schedules.
An award from the NSF-MRI program will enable Georgetown University to purchase a high-resolution scanning electron microscope. The microscope will be located in the Georgetown Advanced Electronics Laboratory (GAEL) and will be shared by faculty members in both the Physics and Chemistry Departments. It will also be made available to other research groups at Georgetown University. Training and use of the microscope will be an important part of the curriculum for physics graduate and undergraduate students, providing them with invaluable skills for future nanoscale research and technology. A short training course will be made available to undergraduate and graduate students and to other interested researchers in the DC metro area.
This award will provide Georgetown University with its first field emission scanning electron microscope (FESEM), a Zeiss Supra 55VP with Nabity lithography system, for high-resolution imaging and electron-beam lithography. Nanoscience is at the core of several funded research programs in the Departments of Physics and Chemistry at Georgetown University, including carbon-nanotube devices for superconducting junctions and chemical sensors, cell transfection micro-needles, nanoporous templates, conducting polymer fibers, real time imaging of nanocrystal nucleation, and nanofabrication of biological reaction chambers. Key features of the instrument are: High-resolution imaging at low accelerating voltages, allowing fast imaging of insulating samples such as carbon nanotubes on silicon dioxide. The variable pressure mode can also be used to control charging effects. Variable pressure mode with ultra-high resolution and variable temperature stage for wet samples, for imaging nucleation of nanocrystals and humidity dependence of the morphology of conducting polymers. E-beam lithography, for patterning of nanotube electron entangler, superconducting proximity effect in junctions with lengths in the submicron range, needles with submicron aperture for cell transfection, and nanochannels for biological macromolecules. Excellent resolution without any special sample preparation, needed for all the research projects. The FESEM will be located in a clean room in the Georgetown Advanced Electronics Laboratory (GAEL) and will be shared by faculty members in both the Physics and Chemistry Departments. Training and use of the microscope will be part of the curriculum for physics graduate students taking the Advanced Characterization course and it will be used during the Laboratory Rotation courses with faculty members who will be major users of the FESEM. A short training course will be made available to undergraduate and graduate students and other interested researchers in the DC metro area.
