Minimizing the Beam Skirt Effect in X-Ray Microanalysis of Nonconductive Samples

Energy dispersive X-ray spectroscopy (EDS) of nonconductive samples in the scanning electron microscope (SEM) requires countermeasures against specimen charging. Variable pressure (VP) SEM is an efficient method, but reduces analytical resolution due to beam broadening by electron scattering in the chamber gas (‘skirt effect’). The local charge compensation (CC) system available with ZEISS SEM and Crossbeam instruments allows EDS of uncoated insulating materials without VP. This note presents experimental evidence of a significantly reduced skirt effect using this method.