CM 200 FEG
The Philips CM200/FEG is a versatile instrument that is designed for analysis of the physical, chemical and magnetic microstructure at high spatial resolution. In addition to high resolution imaging capability, the machine is optimized for analytical electron microscopy and Lorentz imaging, under normal as well as dynamic conditions of variable temperature (77K - 1250K) and applied magnetic fields. Spatially resolved compositional analysis by X-ray emission spectroscopy (Z > 5), local electronic structure measurements by electron energy-loss spectroscopy (Z > 2), convergent beam electron diffraction for three-dimensional structure information, and energy-filtered imaging at the nanometer scale are some of the techniques available on this instrument. In addition, a TEM differential phase contrast imaging technique for quantitative measurements of magnetic domain structures is being developed.
Our recent work on characterizing nanometer-scale Mo-Si multilayers used as zone plates in x-ray optics gives a comprehensive example of the capabilities of this instrument (see below).
For updates or questions, contact Velimir Radmilovic or Zonghoon Lee.
Specifications |
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Accel. Voltage: |
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Spherical Aberration Cs: |
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Chromatic Aberration Cc: |
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Detectors |
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Link energy dispersive X-ray detector with energy resolution of 136eV for Mn k-alpha radiation. |
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Gatan Imaging Filter with 1kx1k CCD camera and energy resolution of .9 eV with 1nm spatial resolution. |
Specimen stages |
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Philips double tilt low background holder |
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Philips single tilt low background holder |
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Gatan 652-Ta double tilt heating holder |
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Gatan 636-DH low background liquid nitrogen cooling holder |
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Low magnification image of a cross-section specimen of nanometer-scale Mo-Si multilayers. |
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X-ray emission scan of the same cross-section sample across a number of layers, clearly resolving the chemical period. |
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A selected area diffraction, with the long multilayer period shown in an enlarged view below. |
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An energy-filtered image using the Si K-edge at ~1839eV loss. |
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A high-resolution image showing the 90Å period. |
A recent highlight of work done on this machine is the study of the conductivity mechanism in manganite perovskites, which showed evidence for O2p hole-driven conductivity in these materials showing "colossal" magnetoresistance.