Strategies to monitor and mitigate sample damage during atomic resolution STEM-EELS spectrum imaging

Gatan instrument used

GIF Continuum^® ER with Stela^®*, and DigiScan™ 3 with eaSI™ technology

Background

A modern scanning transmission electron microscope (STEM) can focus well over 107 electrons per second into an atomic scale probe on a sample; clearly, limiting and monitoring sample damage is a constant concern. A strategy used by the cryo-EM community is to break or “fraction” the electron dose into many subframes so the effects of damage can be monitored. This “dose-fractionation” can be leveraged for STEM electron energy-loss spectroscopy (EELS) data in the same way to limit and/or track the effect of beam damage in a broad range of samples.