The Unit has three transmission electron microscopes, the FEI F20 CRYO FEGTEM, FEI T20 TEM and the FEI Osiris FEGTEM, available for staff and student use. These instruments are suitable for high-end work in both the biological (proteins, vesicles, viruses, bacteria, phages, DNA, thin sections of plant, animal tissue and inorganic material, etc) and material sciences (nanoparticles, metal alloys, polymers, ceramics etc). Specialist techniques: cryo-TEM, tomography, EDX, electron diffraction, Atomic Resoultion, STEM, EFTEM and EELS are available.

  • Training

    To determine your microscopy and training needs, new users are usually required to meet with the EM Officers.  For TEM applications, new users are instructed individually by Mohamed Jaffer (the EM Officer responsible for TEM) or their supervisors. His contact details:

    Email: mohamed.jaffer@uct.ac.za
    Tel +27 21 6503354

    A series of online lectures as an introduction to electron microscopy for biologists is available here: EM for Biologists this covers LM, SEM, TEM and Image Analysis.

  • FEI F20 Cryo TEM

    FEI F20 TEM

    In 2007, the Unit took delivery of the FEI Tecnai F20 field emission cryo-TEM – the first instrument in this class in Africa. Apart from conventional microscopy, this TEM is used for cryo-data collection, cryo-tomography, diffraction studies and microanalysis (EDX). Beam sensitive samples are imaged using the low dose imaging technique.

    The TEM is fitted with a Bruker Quanta 200 XFlash 6 EDX spectrometer that is used for the elemental analysis or chemical characterization of samples. It is capable of giving spectra that indicate which elements are present in the area illuminated by the electron beam. This can be done quantitatively and at the local scale, at the same high magnifications that the TEM can achieve. STEM is not available on this instrument.

    The image recording system is a Direct Electron DE-16 camera. It is a direct detection TEM camera, featuring continuous streaming at up to 92 frames per second, enabling TEM experiments that were not previously possible on a CCD based detector. It features a DDD sensor with 16.8million - 6.5 μm pixels optimized for 200kV, delivering high resolution images over a broad range of magnifications and exposure rates on a 4k x 4k field of view. It also has a 2048 x 2048 integrated near-axis fiber-coupled survey sensor and an integrated Faraday plate for electron exposure measurement. This flexibility allows for the acquisition of high-resolution images in both the biological and materials sciences and allows in situ experiments, low-dose imaging, single particle cryo-EM and tomography to be performed. It comes with the propriety DE software suite. ImageJ and SerialEM are available as well.

    Technical information:

    • High performance in Cryo FEGTEM imaging 200kV with cryo capabilities
    • DE-16 Direct Detection Camera
    • Bruker Quanta 200 XFlash 6 - Energy Dispersive X-ray Analysis Detector (EDX)
    • Low dose imaging
    • Cryo transfer capability with cryobox
    • TEM Scripting
    • Standard single tilt holder and various other sample holders:
      • Gatan 914 high tilt cryo transfer holder and workstation – tilt range +/-80deg
      • FEI Double tilt holder
      • Fischione (Model 2040) dual axis tomography holder
      • Gatan 626 cryoholder and workstation
      • Single-tilt Gatan 626/60 Cryo-transfer holder and workstation with Smartset controller
    • FEI TECNAI F20 FEGTEM Manual (427 pages, 14.5 MB, PDF)
    • Manufacturers website
  • FEI T20 TEM

    FEI T20 TEM

    The FEI T20 delivered and installed in 2010, is a 200kV TEM with a LaB6 filament. The TEM can also be operated at lower accelerating voltages down to 80kV. Energy filter imaging (EFTEM) and energy loss spectroscopy (EELS) can be performed using the Gatan Tridium GIF system.  A 2k x2k Gatan CCD camera is fitted post the Tridiem GIF. Apart from conventional microscopy, this TEM is cryo-enabled and beam sensitive samples is imaged using the low dose imaging technique.

    Technical information

    • LaB6 emitter – 200kV
    • Gatan Tridiem 863 UHS 200kV for Energy Filtered microscopy
    • CCD camera embedded (2048X2048)
    • Low dose imaging mode and cryo transfer capabilities
    • TEM Scripting
    • Cryobox
    • Standard single tilt holder
    • Various other sample holders
      • Gatan 914 high tilt cryo transfer holder and workstation – tilt range +/-80deg
      • FEI Double tilt holder
      • Fischione (Model 2040) dual axis tomography holder
      • Gatan 626 cryoholder and workstation
      • Single-tilt Gatan 626/60 Cryo-transfer holder and workstation with Smartset controller
    • Quick Start Manual (37 pages, 2.67 MB, PDF)
  • Sample Holders applicable to both Tecnai TEM
    • Gatan 914 high tilt cryo transfer holder and workstation – tilt range +/-80deg
    • FEI Double tilt holder
    • Fischione (Model 2040) dual axis tomography holder
    • Gatan 626 cryoholder and workstation
    • Single-tilt Gatan 626/60 Cryo-transfer holder and workstation with Smartset controller
  • FEI Osiris TEM
    • The Tecnai Osiris is an analytical TEM instrument optimised for high speed and high sensitivity EDX measurements in STEM mode. The four windowless Super-X SDD EDX detectors integrated into the pole piece allow detection of up to 200,000 X-ray counts/s over a 0.9 srad solid angle. By combining this ability with the high brightness XFEG gun, EDX maps can be acquired in seconds to minutes.  With a 11 Mpx Gatan Orius CCD camera, the microscope is also suitable for both conventional BF/DF and high-resolution TEM imaging.  In addition to the BF mode, two ADF and a HAADF STEM detector provide a wide range of diffraction and Z-contrast conditions for STEM imaging and analysis.  It is also equipped for EELS/EFTEM analysis.  All in all, a very good analytical TEM for materials science research.