INITIAL GROWTH OF FE ON AU(100) - PREFERENTIAL NUCLEATION, PLACE EXCHANGE AND ENHANCED MASS-TRANSPORT

Scanning tunneling microscopy and scanning tunneling spectroscopy are employed to study the initial stages of the growth of Fe on the ''5 x 1'' reconstructed Au(100) surface. The system shows preferential adsor ption at specific sites of the reconstructed unit cell, place exchange between Fe and Au and incorporation of Fe atoms underneath the surfac e. The amount of material that appears at the surface is much larger t han the deposited coverage of Fe. We show that the excess of material consists of Au atoms originated in the disruption of the surface recon struction and a deposition-induced etching of the substrate steps.