GIF Tridiem ER

The GIF Tridiem ER is specifically designed to realize the significant advance in EELS energy resolution made possible by the advent of monochromated TEM systems. This advanced TEM energy filter includes all the 3rd generation technologies of the 863 GIF Tridiem instrument plus significant enhancements to achieve an intrinsic spectrometer resolution of 100 meV at 200 keV beam energy. With suitable specifications on the monochromated TEM and the room environment, a system energy resolution of 250 meV in measured spectra can be guaranteed.

Please refer to the 863 GIF Tridiem price page for a detailed description of the 3rd-generation technologies and key features offered in the GIF Tridiem line.

The chief added features of the 865 GIF Tridiem ER over the basic 863 model are as follows:

• Specially stabilized lens driver electronics on key filter elements for minimum zero-loss jitter
• Thermally stabilized spectrometer electronics for reduced zero-loss drift
• Three additional octupole lenses for complete 3rd-order aberration correction
• A new decapole lens for partial correction of 4th-order aberrations to achieve even finer spectrum focus
• Improved isochromaticity over the entire EFTEM field-of-view (RMS energy variation reduced by a factor of 3)
• Reduced chromatic distortion, 80% of that of the standard model: 0.25% RMS over 50 eV
• Collection semi-angle for energy-filtered diffraction enlarged by 10%
• Field-of-view for energy-filtered TEM imaging and mapping enlarged by 10%
• Optimized BF/DF STEM detector included and integrated into the filter entrance aperture drive assembly
• Enlarged entrance aperture for STEM EELS work: 2.5 mm versus 2.0 mm
• Two additional high-dispersion settings in EELS mode for high-resolution EELS work: 0.02 and 0.01 eV/pixel

The GIF Tridiem ER entrance optics fully correct focusing aberrations of the prism through third order as well as the most important fourth order component. This aberration correction is achieved via advanced filter autotuning software that quantitatively assesses residual aberrations and precisely adjusts the additional high-order multipole lenses automatically. Typically, this is a one-time adjustment carried out at installation.

Although this model uses the same 5 mm aperture as the 863, the aperture assembly is mounted at a higher position relative to the prism entrance plane to give 10% larger field of view and CBED collection angle. Despite the increased spectrometer acceptance, image distortion and chromaticity are guaranteed to the same low levels as those of the 863 model while image non-isochromaticity is significantly better, with the RMS energy variation reduced by a factor of 3.

The GIF Tridiem ER comes with the same integrated 2K x 2K UltraScan 1000 FT (Frame Transfer) detector and data acquisition and analysis software as the basic 863 model. Since this GIF model is specifically intended for high-resolution EELS work, its detector is only offered with P-type scintillator for maximum dynamic range.

The post-column design of the GIF is ideally suited to analytical work involving simultaneous dark-field STEM imaging, EELS spectroscopy, and EDS analysis. The GIF Tridiem ER further supports this important analytical mode by incorporating an annular dark field STEM detector directly into the spectrometer entrance aperture. This key integration ensures that the same STEM camera length will simultaneously yield optimum collection angles for both DF STEM imaging and EELS spectroscopy. It furthermore provides a robust solution to the problem of mechanical co-alignment of the ADF STEM detector and the spectrometer entrance aperture. Finally, the cinema mode of the GIF Tridiem detector greatly facilitates STEM mode alignments by providing a high-quality live view of the Ronchigram and its alignment with the ADF detector and spectrometer entrance aperture.

The basic instrument consists of a high-resolution, aberration-corrected, energy-filter/spectrometer, including interface flange (for mounting to the TEM or a Gatan camera housing), pneumatic aperture assembly with integrated BF and DF STEM scintillators, PMT with STEM interface electronics, pre-slit multipole assembly, magnetic prism, computer controlled slit, post slit multipole lens assembly, UltraScan 1000 FT detector, and all EELS/EFTEM software components supplied with 863 GIF Tridiem. Where required, a high performance computer workstation is supplied (See Recommended Computer worksheet for details). For complete analytical STEM support, see the STEMPack upgrade option, which includes all additional software and hardware required to perform digital STEM imaging, EELS line scans, and EELS STEM spectrum imaging. For complete details, please see the model 777 STEMPack product. For integration of EDS signals into the data acquisition chain (for single spectra, line scans, and spectrum images), please see the available EDS software options.

As with all GIFs, please note that it may be necessary to purchase special GIF integration options available from the host TEM vendor in order to achieve the full system performance and specifications listed above. In particular, this includes the EFTEM integration option for FEI Tecnai systems and the GIF lens mode option available for JEOL instruments.

Furthermore, at the level of performance made possible by a monochromated TEM and the GIF Tridiem ER, close cooperation between Gatan, the microscope vendor, and the end user’s facility management will be absolutely essential. All components of the total system, including room environment, microscope, and energy filter must be brought into tight compliance with specifications in order for the stated total system resolution to be achieved. Even if one party in this three-way effort takes responsibility for overall system performance, any verification and/or troubleshooting of performance will require close collaboration among all involved parties, especially on those issues that cut across subsystem boundaries and interfaces. Therefore, when quoting or ordering this product, please contact appropriate local representatives of the relevant microscope vendor(s) and of the end user facility and include their contact information in the Notes section of the quote or order.