Formation of Sb submonolayer phases on high index Si(5Â 5Â 12) surface

This work is the first report on the submonolayer adsorption of antimony (Sb) on the high index Si(5 5 12) surface, studied in UHV by in situ surface sensitive probes such as Auger electron spectroscopy (AES), electron energy loss spectroscopy (EELS), and low energy electron diffraction (LEED). The Auger growth curve which is a plot of the Sb(MNN)/Si(LVV) Auger peak intensity ratio with deposition time, provides a calibration of a deposition rate of 0.06 ML/min. A coverage of 0.2 ML is obtained by four different routes (a) adsorption at room temperature (RT), (b) adsorption at high substrate temperature (HT) of 680 °C, (c) annealing the RT adsorbed surface to 800 °C and (d) annealing the high substrate temperature (680 °C) adsorbed surface to 800 °C. The (2 2 5) facets are observed for the RT adsorbed system at coverage of 0.2 ML, while the pathway adopted to attain the 0.2 ML coverage by adsorption at elevated temperature shows two different atomic arrangements in the formation of the (3 3 7) facets. The HT adsorbed surface suggests the formation of nano-wire-like features while the 0.2 ML coverage obtained by annealing the HT as well as RT adsorbed surface suggests an anisotropic Sb atomic arrangement.