The growth, structure, morphology, and composition of Fe films deposited on CoGa(100) at 550 K was studied by thermal energy helium atom scattering (TEAS), Auger electron spectroscopy (AES), and low-energy electron diffraction (LEED). The misfit between the lattice constants of Fe and CoGa is very small (<0.5%) and, thus, at 550 K, a layer-by-layer growth is found. The TEAS and LEED experiments show that iron films grow at 550 K with the bcc-Fe(100) plane parallel to the substrate surface. On the bcc-Fe(100) surface, a c(2 x 2) structure is observed, which is explained by Ga atoms floating on top of the surface. The Ga layer could be removed by Ar+ ion sputtering, and a clean (1 X 1) - Fe(100) structure could be established. (C) 2004 Elsevier B.V. All rights reserved.