The capabilities of the Transmission Electron Microscope (TEM) are applicable to a wide variety of materials, including, but not limited to, polymers, minerals, pharmaceuticals, metals and ceramics. In the TEM, a beam of high-energy electrons is transmitted through a thin (<100 nm) sample. Interaction of the primary beam electrons with electrons in the sample atoms produce a variety of x-ray and electron signals that can be collected as images, diffraction patterns and energy spectra.

The TEM is unique in its ability to provide information about size, morphology, composition, crystallinity and electronic state of a sample, all with extremely high spatial resolution. Because a thin specimen is required, specialized sample preparation techniques such as ultramicrotomy, ion milling or electropolishing are sometimes required. Powders, small particles and colloidal suspensions can often be dispersed on TEM grids with minimal preparation.

Instrumentation:

McCrone Associates uses a JEOL 3010 TEM with:

• 300 kV accelerating voltage
• LaB6 source, FasTEM software for integration of all microscope operations
• High-tilt/high-resolution pole piece
• STEM and backscatter detectors
• Gatan 1.3k x 1k anti-blooming CCD camera for digital acquisition of diffraction patterns
• 2k x 2k high-resolution imaging CCD camera
• Electron energy loss spectrometer and imaging filter with spectrum imaging
• DigitalMicrograph software
• Oxford INCA energy dispersive x-ray spectrometry system with atmospheric thin window for detection of elements down to boron, mapping capability, spectrum imaging and drift correction software.