NaCl(001) surfaces nanostructured by Suzuki precipitates: A scanning force microscopy study

Abstract

Suzuki precipitates on the (001) surfaces of as-cleaved and additionally annealed NaCl:Cd2+ crystals were studied by means of dynamic scanning force microscopy and Kelvin probe force microscopy in ultra-high vacuum. Rectangular precipitates with edge lengths of up to several hundred nanometres can be found on the surfaces of as-cleaved crystals. The precipitates exhibit steps, which are a result of the cleavage of dislocations at the Suzuki-NaCl interfaces. Additional annealing of the crystals below 260 °C leads to surface diffusion and to a restructuring of the whole surface producing atomically flat precipitates at steps, but also on flat terraces in regions of low step density. On surfaces evaporated at 350 °C, the main surface characteristics of evaporated (001) surfaces of pure NaCl can be found. The step edges are merely changed in shape by nanometre-size Suzuki precipitates. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.