Scanning tunneling microscopy study of the Er/Ge(111) c(2X8) interface

Scanning tunneling microscopy (STM) is used to study the Er interaction on the Cre(lll) substrate reconstructed c(2 X 8). In the submonolayer range, a homogeneous two-dimensional (2D) (1 X 1) reconstructed island distribution is observed for an Er deposit at room temperature with an additional annea ling at 500 degreesC. However, when Er is deposited on substrate held at 50 0 degreesC, a significant modification in the surface morphology has been o bserved: 2D islands are accumulated at the step edges due to the high Cre a nd Er atom mobility. Moreover, for temperature under 500 degreesC, STM imag es have revealed the presence of metastable rod-shaped islands. Above 1 ML Er deposit, the interface displays a thin film reconstructed root3 X root 3 R30 degrees with a layer-by-layer growth mode. (C) 2000 American Vacuum Soc iety. [S0734-2101(00)00706-5].