EELS Map: Louise Weaver, Ph.D., Microscopy & Microanalysis Facility, UNB

The (S)TEM can be used to examine internal structure and composition of thin, thinned, or sectioned specimens. Convergent beam electron diffraction provides information on crystal structure and crystallography. STEM and high-angle annular dark field gives information on microstructure, atomic structure and atomic number. Energy dispersive x-ray spectroscopy permits submicrometer elemental identification and compositional analysis. The addition of electron energy loss spectroscopy and energy-filtered imaging allows for the detection of elements at higher spatial resolution, phase identification and bonding information. In summary, the (S)TEM with X-ray and EELS spectroscopy permits further characterization of both organic and inorganic materials.

IMAGING TECHNIQUES

• Brightfield – Conventional mode (CTEM), STEM mode
• Darkfield - High Angle Annular Darkfield (HAADF)
• Electron Diffraction – High Resolution (HR), Selected Area (SA), High Dispersion(HD)
• Energy filtered TEM

ANALYTICAL MODES

• Elemental recognition and phase identification
• Quantitative compositional analysis
• Digital x-ray maps and linescans
• Atomic structure - Z-contrast imaging (HAADF)
• Energy-filtered TEM (EFTEM)
• Bonding analysis - electron energy loss spectroscopy (EELS)

INSTRUMENTATION

JEOL 2011 SCANNING TRANSMISSION ELECTRON MICROSCOPE with:

• EDAX (Genesis) Energy Dispersive X-ray system
• Gatan Imaging Filter (GIF 2000) with EFTEM and EELS capabilities
• Gatan 4k x 4k Ultrascan digital camera
• Gatan DualVision digital camera
• Gatan Cryo-transfer and cooling holder
• JEOL double-tilt analytical holder