Localised Charging Effects Induced By Low Voltage Sem Operation In Non-Conductive Materials

Low voltage scanning electron microscopy (LVSEM) is defined for incident electron beam energies of 5keV or less. The reduction in the electron penetration depth improves spatial resolution for imaging and microanalysis. [1] For low incident electron beam energies, the secondary electron emission coefficient , is enhanced in comparison with what is typically observed in the high energy limit. Thus low voltage operation may help to reduce charging effects in non-conductive materials. Irradiation induced trapped charge produces an electric field within the irradiated micro-volume of specimen which may influence the local structure.