Adsorption of Sb on GaAs(111)B studied by photoemission and low energy electron diffraction

The surface structures resulting from the deposition of Sb on the GaAs(111)B-(2 x 2) surface at room temperature followed by annealing, have been studied by high-resolution soft X-ray photoemission (SXPS) and low energy electron diffraction (LEED). For depositions at room temperature with no subsequent anneal and for annealing temperatures up to 300 degrees C, Sb islands are formed between which the As trimer-based (? x 2) substrate reconstruction of the clean GaAs surface is observed. Annealing to temperatures between 350 and 475 degrees C leads to the creation of Sb chain pairs coexisting with regions of Sb trimers. At 500 degrees C an ordered surface is produced, associated with Sb trimers and an As vacancy.