Focusing of low energy electrons by submicrometer patterned structures in low energy electron microscopy

We report the observation of focusing of low energy electrons by submicrome ter pits patterned onto a silicon crystal surface. Images of an array of pi ts obtained with a low energy electron microscope consist of an array of br ight spots whose diameters depend strongly on the energy of the incident el ectrons. Our electron-optical simulation shows that each pit acts like an e lectrostatic lens, focusing the electrons along its optical axis, with a fo cal position which indeed depends strongly on the incident energy. (C) 2001 American Vacuum Society.