Observation of Surface Micro-Structures by Micro-Probe Reflection High-Energy Electron Diffraction

摘要: A new micro-probe reflection high-energy electron diffraction technique has been developed for observing micro-structures on crystal surfaces. In this technique, an beam of diameter 20 nm at a current 8 nA and angular divergence 2 mrad achieved by using field emission gun, making it possible to obtain bright, sharp patterns from surface micro-areas. spot fluorescent screen is focused apperture optical lens; part the intensity used as signal produce scanning microscope image. This image very sensitive changes in crystallographic orientation, can show areas which orientation change order 0.1 mrad. When was observe Si(111) surfaces metal-deposited surfaces, contrasts caused screw dislocations, atomic steps domain structures were obtained.