When less is more – Reducing dose, damage, and duration with counted EELS
Acquiring high fidelity electron energy loss spectroscopy (EELS) spectra is a long-standing challenge. The combined need for a large energy range (keV), sharp energy resolution (< eV), and simultaneous high dynamic range (orders of magnitude) is a major challenge. Traditionally, EELS is recorded on a single parallel sensor. However, conventional detectors have limited dynamic range and very limited energy range at energy high resolution. These can be improved by taking two spectra in rapid succession, but at the cost of wasted dose applied to the sample (and time for acquisition). Extending further with additional multiple spectra seems like a logical next step. However, this is only practical for the most radiation hard samples and where acquisition time is not a concern. Taking this to its limit, we would go back to the days of serial EELS spectrometers, which could provide a nice spectrum, yet hardly something anyone would genuinely want to revisit.
The dose and time efficient approach for EELS is to acquire a single high-quality spectrum. This is possible today with the K3® – a large-format, direct-detection, electron-counting detector. With 5,760 energy channels in the HD format, the K3 delivers single read spectra with 3 keV of range at <1 eV resolution and 2 keV range at cFEG resolution. While there is no such thing as a perfect detector, in this webinar we will show how the GIF Continuum® with the K3 detector is getting close to perfection and can save you dose, damage, and valuable time at the microscope.