An in situ x-ray reflectivity study of the dynamic evolution of a growing interface was carried out for gold sputter-deposited onto a polished silicon substrate. X-ray reflectivity data were recorded during growth for thicknesses of the gold film ranging from 50 to 3500 Å. A progressive kinetic roughening of the gold-vacuum interface was observed and the time-dependent interfacial width exhibits a power-law behavior. Aided by scanning-tunneling-microscopy measurements the scaling exponents were determined and compared with theoretical studies.

• Received 16 November 1992

DOI:https://doi.org/10.1103/PhysRevLett.70.2900