Isothermal adsorption and desorption studies of In/Si() by reflection high energy electron diffraction and fluorescent X-ray spectroscopy

Isothermal adsorption and desorption processes of In/Si(1 1 1) were studied by reflection high energy electron diffraction (RHEED) and fluorescent X-ray spectroscopy. In the isothermal adsorption process at room temperature, a sticking probability of In on Si(1 1 1) is unity even in a multilayer region, and the 7×7 structure is replaced by 1×1 during adsorption of In up to 2 monolayers (ML). In the isothermal desorption process at temperatures between 360 and 460 °C, superstructure of In/Si(1 1 1) changes to 1×1, 4×1, 31 × 31 , 3 × 3 , 7×7, in turn. Structure change and In desorption from each phase go together and all desorption rates are zeroth order. Activation energies of In desorption from 1×1, 4×1, 31 × 31 and 3 × 3 phases are estimated to 0.48, 1.5, 1.6 and 1.9 eV, respectively. From RHEED and isothermal desorption results, saturation coverage of 4×1 and 31 × 31 phases are estimated to be 0.96±0.15 and 0.56±0.06 ML, respectively.