SCANNING-TUNNELING-MICROSCOPY ON THE GROWTH OF FE FILMS ON CU(100)

We report on a scanning tunneling microscopy study of the condensation of Fe on Cu(100) at room temperature and the influence of subsequent annealing at 100-degrees-C and 230-degrees-C in the coverage range of 0.1-4 monolayers (ML), using an Fe flux of 1 ML/min. After nucleation of the Fe deposit in the form of small islands with single-layer height, the growth proceeds until after coalescence and smoothing of the island structure the growth continues in a layer-by-layer-like mode. In the submonolayer coverage range we found an Fe-induced diffusion of Cu atoms already for room temperature deposition leading to step roughening and formation of two-dimensional Cu islands, which prevent the formation of large two-dimensional Fe islands at low coverages. Annealing the films gives rise to considerable changes of the film morphology due to a large mass transport of Cu atoms.