Configuration of the Spectra 300 at MESA+ NanoLab:
Live iDPC-STEM (patent by TFS). With integrated Differential Phase Contrast (iDPC) STEM the light elements in the Periodic System down to hydrogen can be imaged. iDPC-STEM is also a low dose imaging technique, and is less sensitive to thickness variations in the lamella, making it a powerful imaging option for a variety of materials as is shown in several scientific publications:
Lazić, I. et al., Ultramicroscopy, 2016, 160, 265-280.
Gauquelin, N. et al., Ultramicroscopy, 2017, 181, 178-190.
Nahor, H. et al. Acta Materialia, 2018, 154, 71-78.
Yücelen, E. et al., Scientific Reports, 2018, 8, 2676.
Song, D. et al., Advanced Functional Materials, 2019, 29, 1903843.
de Graaf, S. et al. Science Advances, 2020, 6, eaay4312 (DOI: 10.1126/sciadv.aay4312).
Super-X (patent by TFS). EDS detection system that is comprised of multiple collimated silicon drift detectors (SDDs) resulting in Energy Dispersive X-ray (EDX) spectra with high P/B ratio (Fiori number ≥ 4000). The 4 SDDs are symmetrically distributed around the sample holder. This is to ensure that the same X-ray collection efficiency is guaranteed at each side of the tilt axis when all detectors are switched on. This is important for certain applications such as EDS tomography, and in order to maximize the overall X-ray collection efficiency of the EDS detection system.
Velox microscope operation software on Spectra 300 has several unique features that are of particular importance in EDS applications:
Independent channel and dead time readout of SDDs.
Time resolved spectrum imaging whereby Velox records time resolved STEM and EDS data directly into storage. In case of specimen damage or contamination build-up, Velox provides tools to remove frames from spectrum imaging, therefore spectrum quality is maximized.
Absorption correction algorithm taking multiple SDDs and double-tilt holder shadowing into consideration. In this way, tilt dependent quantification variation is minimized.
With the next generation S-CORR probe corrector (based on the IP by FEI, US8841630B2), STEM imaging aberrations including A5 and D6 are corrected for all high tensions.
Segmented STEM detectors. Besides a conventional HAADF detector, the Panther STEM detection system on the Spectra 300 has in total 16 segments on two detectors.
OptiSTEM+TM to automatically correct for 1st and 2nd order STEM imaging aberrations on the image without the need to look for an amorphous area to obtain the ronchigram.
Operation in the range of 30 – 300 kV, with spatial resolution in probe-corrected STEM at 300 kV ≤ 50 pm, sub-Ångstrom imaging resolution at 80 kV, and at 30 kV ≤ 0.136 nm.
Spectra300 allows future field upgrade with image corrector.
On the Spectra 300, beam defining apertures in the illumination system are heated, ensuring cleanliness that is of critical importance for low kV imaging.
Cold field emission gun electron source that will intrinsically deliver a low energy spread and high brightness. The Spectra 300 is equipped with an extra brightness CFEG (X-CFEG). Moreover, a beam current of ≥ 100 pA is guaranteed at each specified corrected STEM resolution, ensuring that the brightness criterion is met.
In unit cell reconstruction studies, the CrystalPack package on Spectra 300 allows to move from one zone axis to another conveniently by making the β-tilt compucentric. Therefore, the region of interest can be kept in the field of view when a β-tilt is introduced.
Alignments at 300, 200, 80 and 30 kV in both TEM and STEM with fast and easy switching.
Full electron tomography set (hardware and software) for TEM, STEM, EDX. The full workflow from acquisition of data including visualization and analysis is supported by in-house developed solutions by Thermo Fisher Scientific.
