Carbon-based nanomaterials and other low-dimensional materials have promising application in a variety of industries including electronics and filtration. Research into these novel materials has produced increased interest in low-kV scanning transmission electron microscopy (STEM) due to the technique’s ability to produce images with atomic resolution. This capacity is, however, significantly impacted by radiation; beam-damage-free imaging can often only be achieved at low accelerating voltages below the knock-on damage threshold (typically under 60 kV).
At these low values, resolution-limiting aberrations can substantially undermine imaging efforts. Monochromation of the electron beam, or the use of a cold field emission gun, have proven to be reliable ways to reduce chromatic blurring. A probe corrector can further improve signal by reducing, or potentially even eliminating, aberrations at low accelerating voltages.
Thermo Fisher Scientific combines monochromation and probe correction in the Thermo Scientific Spectra S/TEM product line, offering an ideally suited solution for imaging 2D materials. With the Spectra S/TEM, accelerating voltages as low as 30 kV are possible due to the superior correction capability of the Thermo Scientific S-CORR Probe Corrector along with the Thermo Scientific CETCOR Image Corrector, which compensates for spherical aberrations.