The Initial Stages of Cu Deposition on Au(100) as Studied by in situ STM: The Epitaxial Growth of bcc Cu*

growing pseudomorphic. From the height of these Cu layers and from their lateral atomic arrangement it is concluded that initially Cu is deposited onto Au(100) in the bcc structure. With the 11th layer, however, a structural transition takes place which causes the Cu overlayer to become buckled. This is caused by a sudden reduction, in striped regions, of the Cu-Cu distance from 0.29 nm in the pseudomorphic state to 0.26 nm as in the fee Cu bulk state, while the dark regions between the stripes appear to be still pseudomorphic. The rather complicated atomic arrangement of the 11th layer is explained in terms of strain relief during the bcc-fcc transition that avoids on-top positions of the atoms. The influence of surface defects, such as monoatomic high gold islands, on the growth behavior and the domain structure of the Cu overlayer is briefly addressed.