LAUSR

Contamination and charging of the specimen is a common issue in electron microscopy and can lead to disturbing artifacts in transmission electron microscopy (TEM) and especially in scanning (S)TEM, where a focused electron beam is impinging on the sample [1]. However, these effects can also be utilized beneficially, e.g., in electron-beam induced deposition or in hole-free phase plate (HFPP) TEM [2,3]. To better understand the underlying mechanisms of contamination and charging, we studied amorphous thin films under focused electron-beam illumination with high intensity using electronenergy loss spectroscopy (EELS), HFPP imaging and secondary electron (SE) detection. The experiments provide insight in the behavior of contamination buildup, allow a clear separation between contamination and charging effects and give a possible explanation for the origin of the HFPP image contrast. We also investigated different techniques to reduce or even prevent contamination.