Geophysical Sciences
FIB-SEM
Figure: The LYRA3 at the University of Chicago.
FIB-SEM
The FIB-SEM facility in the Department of the Geophysical Sciences at the University of Chicago features a TESCAN LYRA3 field-emission scanning electron microscope (FESEM) with a focused ion beam (FIB).
SEM
The SEM can operate at high vacuum for conducting samples or coated insulators and at low vacuum for insulating samples, and is equipped with the following detectors and other capabilities:
Everhart-Thornley secondary electron (SE) detector, for topographic imaging at high vacuum
Scintillator-type backscattered electron (BSE) detector, for compositional imaging at low and high vacuum
In-column SE detector for high resolution topographic imaging
In-column BSE detector for high resolution compositional imaging
Scanning transmission electron microscopy (STEM) detector with bright-field and dark-field capability
Beam deceleration for high resolution imaging at low incident electron energy
Two Oxford Instruments X-Max-80 silicon drift x-detectors (SDD), for rapid chemical mapping and quantitative chemical analysis
An Oxford Instruments Wave 500 wavelength-dispersive spectrometer (WDS) for low-concentration chemical analyses
An Oxford Instruments NordlysMax2 electron backscatter diffraction (EBSD) detector for determination of crystal structures and study of textures
SEM applications
High and low resolution imaging (cm- to nm-size)
Chemical analysis and chemical mapping
Structural analysis by EBSD or TKD (Transmission Kikuchi Diffraction)
FIB
The LYRA3 is equipped with a Cobra liquid metal ion gun that emits a focused beam of gallium ions. The current of the gallium beam can be varied between ~30 nA and <1 pA. It is currently used for milling, imaging, and controlled deposition of carbon and platinum. The latter is achieved using an Oxford Instruments OmniGIS II gas injection system. An Oxford Instruments OP-400 micromanipulator can be used to lift out small milled samples. The OmniGIS II is currently set up for carbon and platinum deposition, but can also be equipped for deposition of tungsten, and for enhanced milling with reactive gases (XeF2 for SiO2 and H2O for carbon).
FIB applications
TEM sample preparation
Tomography
Manipulation of small samples (controlled isolation or removal of material, controlled deposition of carbon and platinum)
Enhanced lateral resolution of EDS analyses using thinned specimens
Want to use the FIB-SEM?
We welcome users from within and outside of the university. Rates vary based on application and user level. We offer training, operator-assisted and independent use of the instrument. Contact us at FIBSEM-manager@uchicago.edu for more details or to schedule a session.
Figure: Example of a BSE image and elemental maps obtained with the LYRA3 and Oxford instruments EDS detector at the University of Chicago (modified from Kööp et al., 2016).