Very low energy scanning electron microscopy

An overview of recent developments in very low energy scanning electron microscopy is presented. Electron optical aspects are briefly summarized including the low energy beam formation in a cathode lens equipped column, comparison of the sequential and overlapped electric and magnetic fields in the objective lens, and detection issues including extension to the transmitted electron mode as well as to the multichannel detection of signal sorted according to the polar angle of emission. In addition to the acquisition of contrasts specific for the very low energy range, advantages of detection of electrons backscattered to large angles from the surface normal are demonstrated on selected application examples.