The adsorption of Sb on InAs(110) studied by photoemission and photoelectron diffraction

Abstract

The adsorption of Sb on InAs(110) was studied for room temperature (RT) deposition and subsequent annealing using high-resolution soft X-ray photoemission (SXPS). A line shape analysis of the Sb 4d core level emission reveals that the Sb deposition at RT does not lead to perfectly ordered growth of the first monolayer. Subsequent annealing, however, results in a highly ordered first monolayer which is stable up to 620 K. This was confirmed by the Sb 4d core level emission line shape consisting of two well resolved chemically shifted components, which can be assigned to two different adsorption sites in the epitaxial Sb monolayer. The changes of surface band bending were determined as a function of Sb coverage and annealing temperature revealing that an accumulation layer was formed. The geometrical structure of the epitaxial Sb monolayers was investigated using low-energy photoelectron diffraction, i.e. the intensity of the Sb 4d core level emission was monitored as a function of polar angles and photon energy. The resulting patterns which show strong variations for both components are compared to calculations using a multiple scattering cluster model for different adsorption models of the Sb monolayer.